DE102004058520B3 - Flue-gas losses measurement system for boiler burning fuel has vertical cylindrical vessel with graduations on side and has side entrance leading to vertical pipe connected to overflow hose - Google Patents

Abstract

Water collects in a container (100) with a transparent wall (144) having graduations (101). Water enters through a side connection (104) near the bottom of the container. It flows into a vertical measuring pipe (140) with a connection (141) for a flexible overflow hose (142) clamped at a given level in a holder (149) at the top of the container.

Description

The The invention describes a measuring method for determining the exhaust gas loss of combustion plants (net exhaust gas loss), in which in the hearth (boiler) or in the exhaust system at least during normal operation, a part of condensed out during combustion of water formed. The invention is particularly suitable for condensing boilers as a heat generator, it can be but also in low-temperature boilers with significant condensation in the fireplace and in other heat generators (e.g., fuel cell, power heater).

Also the loss of flue gas from fireplaces (Gross exhaust gas loss) can be determined with the invention.

Preliminary remark: Gross and net exhaust gas loss:

In the technical literature and even in state regulations is not always strict enough between the "gross exhaust gas loss" as the heat content of the exhaust gas Leaving the boiler and the "net exhaust gas loss" (NAV) as real Flue gas loss of the entire combustion plant distinguished. (After Definition of 1.BlmSchV / 1 / includes the term "combustion plant" the entire system of fireplace and Exhaust system).

So we call "net exhaust gas loss" (NAV) the heat flow of a combustion plant that leaves the heated area of a building unused via the exhaust system. In order to reach the NAV, the gross exhaust gas loss, which is measured annually by the chimney sweep in conventional boilers according to the 1.BlmSchV, must be deducted from the "chimney heat" which flows through the chimney walls to the house to be heated or if necessary also to the combustion air , So we define: Net exhaust gas loss (NAV) = Gross exhaust gas loss - Fireplace heat (1) Gross exhaust gas loss = heat content of the exhaust gas directly behind the heat generator, relative to a reference temperature (eg basement or outside temperature) (1a) Fireplace heat = fireplace wall heat + preheating combustion air (1b)

The conceptual confusion comes about because the measured Gross exhaust gas loss in public already referred to as "exhaust loss" par excellence becomes and in the current version of the 1. BlmSchV even as the legal to limit loss.

The Confusion becomes even bigger by that the original one Regulation text of the 1. BlmSchV until 1997 was physically correct and a limitation of the net exhaust gas loss, namely the "waste gas loss of the combustion plant" demanded. The However, this prescribed measuring regulation only determined the gross exhaust gas loss. After appropriate provision (summary in / 2 /) and announcement corrected a legal review the legislature in the amendment in 1997 not the faulty and physically nonsensical measurement rule, but changed the until then completely correct text of the regulation: instead of limiting the "waste gas loss of the Furnace "was now the limitation of the "waste gas loss the hearth "to the goal of the decree.

Of the deeper reason for this conceptual confusion is probably in the background superficial Mindset that the heat, which is not transferred from the boiler to the heating medium water, already definitively as Loss was recorded. This approach may indeed for the Design of boiler plants to be acceptable: from a practical point of view It depends on the fact that the boiler is also the coldest Time enough Perform. To determine the Einsparpo potential at However, combustion plants must have the retroactive effect of gross heat losses taken into account for the object to be heated become. So it is generally indisputable that both on the Exhaust system as well over the warming a boiler room heat gains be discharged to the object to be heated. At a reduction the gross heat losses the fireplace becomes natural also the recoverable from it Heat reduced: the larger heat output to the heating water is therefore a lower heat absorption from the partial recovery the gross heat losses across from. The alleged savings then often even prevail Part of a mere Displacement of useful heat flows (/ 2 /).

It is therefore obvious that for the estimation of a saving potential only the net heat losses, So heat flows, the the heated object in any way benefit, considered be allowed to.

1.1. Gross flue gas loss

On the Efficiency or degree of utilization of fireplaces ("gross exhaust gas loss") exists an extensive literature (e.g .: / 3 /, / 4 /). Here is a distinction between the one hand a current value, which (in conventional boilers), for example as "exhaust gas loss the fireplace "after the procedure the first regulation of the Federal Immission Control Act / 1 /) with the help of Siegert's formula the CO2 content and the exhaust gas temperature can be determined, and on the other hand, an annual utilization rate, in the determination of which certain structure of the performance decrease over the year provided becomes.

The measurement procedure according to 1.BlmschV can not be applied directly to condensing boilers, as the condensation heat of the precipitated combustion water is not taken into account. Therefore, previously omitted in condensing systems (- ie in furnaces with condensing boilers -) on a direct measurement of exhaust heat, but determines the boiler loss as the difference between the heat content Q _{gas of} the amount of gas used and the amount of heat absorbed by the hot water heating Q _water Q gross = Q gas - Q water (2)

The Gas volume is measured with the gas meter and the heat flow in the heating network with a Heat meters. Of the Heat meter measures the water flow and the temperature in front of and behind the boiler / 5 /.

Although the measuring method according to equation (2) is transparent, it is unfortunately very inaccurate. Since the determinant of interest Q _{gross is} about an order of magnitude smaller than the direct measured quantities Q _gas and Q _water , the well-known problem arises of the "small difference between two large numbers". For example, a relative measurement error of 3% for the heat meter and 2% for the gas meter (including the errors resulting from the fluctuating gas composition and temperature) results in a maximum total error of 5 percentage points, which is a relative error of approximately 50% on the relative accuracy of the boiler loss Q _gross . The method is therefore very inaccurate for a single investment and useful at best for statistical statements about a total of many plants.

In DIN 4702/10 / are "rules for the Heating test of boilers "with and without exhaust condensation. This laboratory method is suitable but not as a routine measurement for the heating operator.

bird / 11 / also has the gross exhaust gas loss of gas condensing boilers derived; as an additional new one Measured value he uses the relative humidity of the exhaust gas (directly at Boiler output). The method described in / 11 / is as an extension the chimney sweep measurement according to 1.BlmSchV thought; as a routine measurement too for the Heating company, she is less suitable.

1.2. Net flue gas loss

The described in section 1.1 Difference method according to equation (2) can be do not apply to the net exhaust gas loss, as the fireplace heat is basically not is detected. This applies to both conventional Boiler as well for Condensing boilers.

Currently is the net exhaust gas loss of existing combustion plants from the established experts are not measured and therefore there are none corresponding guidelines.

Nevertheless, by laying the measuring point in the exhaust pipe at the end of the heated zone of the building, for example at the upper cleaning flap of the chimney, the established methods could also be used to measure the net exhaust gas loss:
In conventional boilers without condensation in the chimney, the net exhaust gas loss can be determined directly using the Siegert formula (/ 2 /, see also Section 3.1). For condensing boilers must - like already mentioned in section 1.1 - a further parameter such as the exhaust gas humidity / 11 / be used; However, this is normally not a problem, since the relative humidity of the exhaust gas after a longer path through the exhaust pipe practically 100% achieved (see Section 3.2), so no longer measured but only mathematically must be considered.

These However, adapted established measuring methods are used as a correction of Chimney sweeper measurement thought / 2 /; as a routine measurement for the heating operator they are less suitable. Above all, they only deliver one Instantaneous value, but with condensing boilers because of the strong Influence of the return temperature on the condensation of the combustion water is completely unsatisfactory. For condensing boiler an integral measuring method is needed.

2nd task and approach

Just the net exhaust gas loss indicates the physically available potential to save exhaust gas losses through investments and operational management. Therefore exists for Condensing systems a need for a simple, inexpensive and time-integrating measuring methods, also in individual cases is sufficiently accurate.

With the invention is intended for the actual heat loss of the building relevant net exhaust gas loss of a condenser operated Firing system to be determined. By a simple adaptation can the gross exhaust gas loss of the fireplace, as he for example is defined in the 1.BlmSchV or in the DIN 4702, also measured become. The measuring method should be so simple that it also from the heating operator carried out and that the result can be provided cheaply as a gauge can be. Also, the measurement method is not just instantaneous but above all averages over larger periods or even over provide the entire heating season, since only by the strong influence of Return temperature the heating system can be considered on the exhaust gas losses.

This The aim is achieved by the method described in patent claims 1 and 2 Fulfills. One to carry the method suitable device of the type "controlled emptying a storage container with Counting "is in progress 4 and such a device of the type "pulsed emptying of a buffer on a Water meter " Described in claim 10.

advantageous Embodiments of the method and the devices are in the dependent claims specified. embodiments The invention are illustrated in the drawings.

to solution the problem becomes the Siegert'sche Formula extended by a condensation term and shown as determine the exhaust gas losses essentially from the amount of condensate to let. Suitable devices for condensate measurement in condensing systems are specified.

3. Determination of the net exhaust gas loss

3.1 Determination of the NAV at conventional combustion plants

For the annual measurements prescribed under 1.BlmSchV / 1 / for conventional combustion plants, the gross exhaust gas loss is measured. The chimney sweep measures next to the cellar temperature T _cellar immediately behind the boiler (here referred to as point "0") the temperature T _Abg (0) and the CO ₂ content (= [CO2]) of the exhaust gas flow and determines it with the Siegert ' formula q Abg '(0) = (A / [CO2] + B) · (T Abg (0) - T basement, cellar ) (3) the current gross exhaust gas loss q _Abg '(0), which is a fraction of the rated thermal input Q _F '. Usually, q _exhaust (0) and [CO2] are given as a percentage, with the CO2 content being referred to as volume percentage of the dry exhaust gas. For natural gas, the following values are used for the substance constants A and B: A = 0.37 [%] and B = 0.009 [% / K] for natural gas. (4)

Incidentally, the Siegert formula only provides one on the rated thermal input Q _F '(calorific value) related, practical technical formulation for the sensible heat content of an exhaust stream. In practice, all variables are determined in the "thermal equilibrium"; then one can interpret the instantaneous values as equilibrium values and omit the upper index "'". However, with a view to a later generalization, we differentiate, from the beginning, between momentary performance data (with the time-derivative index "'") and work data; which we will not designate for a uniform exhaust gas (with temporally unchanged temperatures and mass flow) with the lower index "g" and in the general case at all.

Using the same measuring method - just at the right measuring point at the end of the heated zone at height H in the chimney - the instantaneous net exhaust gas loss (NAV) can also be determined: q Abg '(H) = (A / [CO2] + B) * (T Abg (H) - T basement, cellar ) (5)

The NAV could also be determined indirectly from the measurement in the boiler room according to equation (3). The chimney heat results from the cooling of the flue gas inside the chimney and can also be determined by calculation. For this purpose, the method described in DIN 4705/6 / for determining the exhaust gas temperature at a height H in the chimney can be used: T Abg (H) - T u = (T Abg (0) - T u ) · Exp {-K} [(equation (8) of DIN 4705)] (6) with the cooling rate K K = H * (U * k) / (m '* c p ) [Eq. (11) of DIN 4705] (7)

H here denotes the "stretched" length of the exhaust pipe between the measuring point of the 1.BlmSchV and (for example) the upper cleaning flap as a reference point for the NAV. The exact meaning of the other variables (ambient temperature T _u , inner circumference U, heat transfer coefficient k, exhaust gas mass flow m 'and specific heat capacity c _p ) is taken from DIN 4705. It should be noted that in the theory of heat exchangers the "number of transfer units (NTU) "corresponds to the" cooling rate "K of DIN 4705.

To the 1st BlmSchV will make the determination of gross exhaust gas loss practical all conventional boilers required. Condensing boilers However, these are from this annual Examinations except in the Siegert's formula (3) the Condensation of the water vapor within the boiler or the firing system not considered becomes.

in the The following is intended to show that in condensing appliances, the Loss of exhaust even in a particularly simple way determine. The measuring device used in the presented measuring method can be assembled from individual parts whose cost is lower is as the metering fee for a one-time Measurement according to the 1st BlmSchV.

3.2 The net exhaust gas loss of condensing plants

The combustion of one cubic meter of natural gas (calculated as pure CH ₄ ) produces one cubic meter of CO ₂ and two cubic meters of water as combustion product: CH ₄ + 2O ₂ = CO ₂ + 2H ₂ O (8)

The excess air of the combustion air can therefore be determined both from the CO ₂ content and from the oxygen content of the exhaust gas.

For the following Let's look first a uniform Operation of the furnace, which we express by the index "g".

The exhaust gas loss according to Siegert's equation, Eq. (3) or Eq. (5), does not yet take into account the heat of condensation of the discharged water vapor. However, this can easily be corrected if we introduce the condensation heat Q _WD0 in Eq. (3) or in Eq. (5) q Abg, g = (A / [CO2] + B) (T. Abg - T basement, cellar ) + Q WDo / Q F ; (9) Here, Q _WD0 / Q _{F is} the proportion of the total heat of condensation Q _WD0 at the still on the calorific value related combustion heat Q _{F of} the fuel used. Now we consider the integral value of the net flue gas loss, Q _Abg (H), the t in a certain time interval ₀ occurs, the result is Q Abg, g (H) = Q F · (A / [CO2] + B) (T. Abg (H) - T basement, cellar ) + Q WD 0 (10)

Now, the question arises, how does the equation (10) change if the entire water vapor WD ₀ no longer leaves the chimney as vaporous water, but the condensate quantity W in the boiler and / or in the chimney is recovered. Let w denote the proportion of the condensed water quantity W in the total theoretical combustion water WD ₀ , ie w = W / WD 0 (11) this gives the recovered heat of condensation Q _W to: Q W = w · Q WD 0 (12) and the heat of condensation remaining in the exhaust gas becomes (1-w) * Q _WD0 . The amount of maximum possible combustion water, WD ₀ , can be determined from the amount of combustion heat Q _F or directly from the gas consumption in m ³ , V _G : WD 0 = x Q0 · Q F with about x Q0 = 0.16 [liter H2O / kWh] for natural gas (11a) WD 0 = x V0 · V G with about x V0 = 1.6 [liters H2O / m n 3 ] with natural gas (11b)

However, water in the exhaust gas condenses only when it falls below the dew point. If the flue gas is already condensing in the (condensing) boiler, a further condensation usually takes place in the flue. Due to the relatively poor removal of the fireplace heat and the good heat transfer from the moist exhaust gas to the chimney wall, the temperature difference between the saturated with water vapor exhaust gas and the chimney wall decreases very quickly. It follows that in a chimney operated in the condensation zone, the exhaust gas leaves the chimney at a temperature which corresponds approximately to the dew point temperature, T _{dew point} , determined by its residual water content. Furthermore, one must take into account that the condensed water no longer contributes to the sensible heat of the exhaust stream; this shortfall is independent of the combustion air ratio, which is taken into account in Siegert's formula by the CO2 content [CO2]. In the case of a uniform exhaust gas flow, the total exhaust gas loss then results in:

Equation (13) contains, in addition to the CO2 content as a measured variable, only the condensate fraction w. The dew point temperature can be calculated, for example, from the scheme given in DIN 4705 (see Section 3.21). The contribution B _{H2O of} the combustion water to the constant B can be determined from a simple combustion balance (see Section 3.22). For the fraction of the heat of condensation at the calorific value, a substance constant of the fuel, one can use 0.11 for natural gas: Q WD 0 / Q F = 0.11 = 11% for natural gas (14)

The heat content of the liquid condensate, which is otherwise very small compared to the heat of condensation Q _WD0 , is not explicitly considered in (13); this boils down to the fact that the condensation water near the temperature T _cellar is drained into the sewer.

3.21 Dew point temperature T _{Dew point} (w)

The exhaust gas temperature at the outlet of the chimney, which differs only slightly in the condensation mode from the exhaust gas temperature at the upper cleaning flap, can be determined for the reference CO2 content [CO2] _ref from the degree of condensation of the combustion water. With the aid of the approximation equations of DIN 4705/7 /, the unsaturated ("condensate-free") water vapor content initially results for an exhaust gas with the CO2 content [CO2] [H2O] u = 100 / (1 + f w / [CO2]) [in%] (15) where for f _w the following numerical values are given:
f _w (natural gas H or L) = 57 [%]
f _w (fuel oil EL) = 111 [%]
and the combustion air is initially assumed to be completely dry.

The water content remaining after the condensation of the water quantity W in the exhaust gas results from the multiplication of equation (15) by a factor which relates the still steamy amount of water to the total combustion water WD ₀ : [H2O] = (WD 0 - W) / WD 0 · [H2O] u + 1,1 = (1-w) · [H2O] u + 1.1 (16)

It was also in equation (16) based on DIN 4705 still an initial moisture added to the combustion air of 1.1%.

angegeben. Setzt man in Gl.(15) den Referenzwert [CO2]_ref ein so lässt sich aus den Gl.(15) bis (18) hierfür der Taupunkt des das Abgasrohr verlassenden Abgases berechnen.From a water vapor content [H2O] the water vapor partial pressure results P WD = [H2O] / 100 · P L (17) where P _L denotes the external air pressure, ie under normal conditions 101.3 [kPa]. The dew point of an exhaust gas with the water vapor partial pressure P _WD is in the DIN 4705/6 / with

specified. If the reference value [CO2] _ref is used in equation (15), the dew point of the exhaust gas leaving the exhaust pipe can be calculated from equation (15) to (18) for this purpose.

3.22 The contribution B _{H2O of} the water vapor to the sensible exhaust heat

With regard to the ambient temperature T _u , the sensible heat content Q _{Abg, f, g of} an exhaust gas with the mass m, the specific heat capacity c _p and the temperature T _Abg : Q Abg, f, g = (T Abg - T u ) (M * c p ) (19)

The mass m of the exhaust gas is composed of the masses of all exhaust gas components i. Therefore: m * c p = Σm i · c pi (20)

If the fraction w is missing in the exhaust gas component water vapor because this water has condensed out, then the sum in (20) must be reduced accordingly (M · c p ) w = Σm i · c pi - w · m H2O · c pH2O = m · c p - w · m H2O · c pH2O ; (21)

A fuel with the mass m _B and the lower calorific value H _B gives a combustion heat Q F = m B ·H B (22)

The relative, sensible exhaust gas loss of the partially condensed exhaust gas is obtained by substituting the special case (m · c _p ) _w according to Eq. (21) for the factor (m · c _p ) in (19) and the entire expression on Q _F (22) normalized: q Abg, f, g = (m / m B · c p /H B - w H2O / m B · c pH2O /H B ]) * (T Abg - T u ) (23)

In the case without condensation (w = 0) one can identify (23) with the Siegert formula (3) and therefore use the corresponding constants from (3) for the first summand in (23). This gives you q Abg, f, g = (A / [CO2] + B - w · m H2O / m B · c pH2O /H B ]) * (T Abg - T u ) (24)

The comparison of (24) with the first summand of (13) yields for the constant B _H2O introduced there:

Note that c _{pH2O denotes} the specific heat capacity of the water vapor.

Let's use the numerical values for the combustion of natural gas:
m _H2O / m _B = 2 · 18/16 = 2.25 (natural gas calculated as CH ₄ )
c _pH2O = 1.92 [kJ / (kgK)] at 50 ° C (/ 8 /)
H _B = 37300 / (0.61 x 1.29) = 47401 [kJ / kg] for natural gas H (/ 9 /)
the constant B _{H2O is given} by (25)
B _H2O = 2.25 x 1.92 / 47401 = 0.000091 [1 / K]
in percent:

3.23 Uneven exhaust gas flow

In the case of a uniform exhaust gas flow, which we characterize by the distinction g, the total exhaust gas loss according to Eq. (13) results in: Q Abg, g = Q F · (A / [CO2] + B - w · B H2O ) * (T dew point (w) - T basement, cellar ) + (1 - w) · Q WD 0 [(13)]

The exhaust gas loss Q _{Abg, g} can be subdivided into a fraction of sensible heat Q _{Abg, f, g} and into the condensate tank: Q Abg, g = Q Abg, f, g + (1 - w) · Q WD 0 (13a)

Now consider a time-varying non-uniform exhaust flow in a time period t ₀ . We assume that the cellar temperature T _cellar and the CO2 content [CO2] do not change significantly over t ₀ and from the outset calculate with the time averages of these two quantities. The total exhaust loss is then:

Here, Q ' _F (t) are the current firing heat output and w (t) is the current condensate fraction at time t. The integration extends over the time range t ₀ . Note that the second summand in (27), which includes the condensation heat of the precipitated condensate, is not affected by the temporal variability of the exhaust gas flow, since it is already an integral quantity.

In the following, therefore, we consider only the first part of (27), that is, the integral _{expression that} gives the sensible heat of exhaust Q _{Qd, f} :

und w(t) stellt den momentanen Kondensatanteil des Verbrennungswassers dar, also w(t) = W'/WD0' = (dW/dt)/(dWD0/dt) It applies

and w (t) represents the instantaneous condensate fraction of the combustion water, ie w (t) = W '/ WD 0 '= (dW / dt) / (dWD 0 / Dt)

und nicht verwechselt werden darf mit dem Mittelwert w_m des momentanen Kondensatanteiles w(t), der uns hier nicht weiter interessiert:

Note, however, that w (Eq. (11) indicates the integral value of the condensate fraction, ie

and should not be confused with the mean value w _{m of} the instantaneous condensate fraction w (t), which we are not interested in here:

Normally you will not be able to press the exhaust temperature below the room temperature of the building; On the other hand, one can not rule out that at high firing capacity, for example in the preparation of hot water, practically no more condensate. Therefore you can w (t) for the usual [CO2] content in the value range 0 <= w (t) <w Max with w Max ~ 0.8 to 0.85 depending on [CO2] content (30) limit.

The dew-point temperature can be calculated according to Section 3.21 and can also be represented in closed form from Eq. (18) by continuously inserting Eqs. (17) to (15). It can then be seen that T _{dew point} (w) decreases more and more with increasing condensate fraction w, ie a concavely curved function that decreases monotonously with w, ie the slope dT _{dew point} (w) / dw is negative and a monotonically decreasing function. From the functional course of the individual factors of the integrand in Eq. (28) one can obtain theoretical lower and upper bounds by examining extreme distributions of the condensation attack w (t), which, however, must be compatible with equations (29) to (30) for Q _{Abg, f} derive. However, this should not be detailed at this point.

A close estimate for Q _{Abg, f} is obtained by first using (28) for the time-varying condensate fraction w (t) whose integral mean value w: Q Abg, f, 1 = t 0 · [Q ' F (w) · (A / [CO2] + B - w · B H2O ) * (T dew point (w)) - T basement, cellar )] (31) and then instead of t ₀ .Q _F '(w) in (31) the actual firing heat Q _F begins

With In equation (32) we again have the sensible part of the exhaust gas heat in the case a uniform Process (see Eqs. (13) and (13a)). The above However, consideration should make visible what simplifications its acquisition as an estimate for the nonuniform Case includes.

The estimated value Q _{Abg, f, g} may prove to be useful in most practical cases, which of course is partly due to the fact that in equation (27) the heat of condensation (second summand) outweighs the sensible heat. Nevertheless, in order to show the possibility of improvement of the estimation and to consider empirically, we introduce an additive distribution coefficient eps _-q , which considers or empirically covers the influence of the temporal distribution of the instantaneous condensate component, w (t).

In most cases one would like to indicate the exhaust gas loss in percent of the firing heat Q _F related to the lower calorific value H _u :

It turned out that the case of the uniform exhaust gas flow (ie w (t) = const. = W) with eps _-q = 0 gives the upper limit of eps _-q and all deviating distributions have an eps _-q that is negative but remains small in its absolute value. In the practical distributions I tested, eps _{-q was} always smaller than 0.3, and in most cases even less than 0.2 percentage points. In a first approximation, therefore, eps _-q = 0 can be set.

Reference to a simple Rule of thumb, the equation (43)

Considering the size ratios of the summands in Eq. (33a) and bearing in mind that not everyone wants to fully exploit the precision inherent in the method, in section 5.2 natural gas becomes a simple but astonishingly accurate rule of thumb which equals (43) , given and discussed for q _Abg :

Comments on gross exhaust gas loss:

• 1. The exhaust gas temperature at the outlet of the boiler is a few K above the dew point depending on the load. The boiler manufacturers provide corresponding calculation values for the design of the exhaust system according to DIN 4705; these excess temperatures are usually between 5 and 15 K. In determining the gross exhaust gas loss, this can be taken into account either by adding an excess temperature derived from the abovementioned manufacturer's instructions in Eq. (32) in the temperature clamp or directly instead of T _{dew point} ( , w) is the measured in accordance with the 1.BlmSchV exhaust gas temperature T _Abg (using 0) being the argument "0" here, the height H = denotes 0, - to display so that there is a temperature measurement of the exhaust gas directly to the boiler output , So:
  
  In the case of the condensate fraction w, however, care must now be taken to ensure that only the condensate from the boiler is used for its determination, since the condensate from the chimney is not taken into account in the gross exhaust gas loss.
• 2. Our definition of gross exhaust gas loss in Eq. (1a) is Although obvious but not inevitable: instead of the basement or outside temperature could the gross exhaust gas loss on the inlet temperature of the combustion air at the fireplace refer, and this temperature can in the exhaust air supply air method noticeable differ from the basement temperature. With such a definition you would So part of the back in the fireplace gained heat at the fireplace book and not as fireplace heat conceive. This procedure would be but also problematic because, for example, when the attic and lower exhaust gas temperature at the end of the chimney the cold combustion air in the gap between the exhaust pipe and brick chimney not only on the exhaust pipe but also on the (even larger) inner surface of the Chimney cheeks - so with useful heat warmed up becomes. Equation (34) would have to then by an estimate the air preheating heat are supplemented. - because the Gross exhaust heat but anyway for the potential for saving energy is uninteresting, you need not to deepen the problem.
• 3. For the gross exhaust gas loss of a gas boiler Vogel (11) has an equation derived in the as additional Measured value instead of the condensate fraction w the relative humidity of the exhaust gas is measured. For a unique technical measurement of the current combustion technology Efficiency, this is not objectionable. For an integral measurement over a longer Period, however, is the integral measure of condensate percentage in my view clearly preferable. Furthermore the condensate attack is a very cheap, simple and also for laymen "comprehensible" measure.

4th embodiments for measuring the condensate water

4.0 Overview

The condensate of a combustion plant falls continuously over the entire heating period, but in a small amount of electricity. A numerical example may clarify this: Stoichiometrically, natural gas H yields about 1.6 l of condensate per m ^{3 of} natural gas. If one limits his technical ambition to an exhaust gas temperature above room temperature, then a maximum condensation water fraction of approximately w _max = 0.85 must be expected, whereby this value still depends somewhat on the CO 2 content of the exhaust gas. In practice, then with a maximum of about 1.4 liters of water per m ^{3 of} natural gas can be expected. With an average firing capacity of Q _F = 10 [kW] (this corresponds to 1 m ^{3 of} gas per h), a mean condensate flow rate of 1.4 [l / h] = 0.00039 [l / s] = 0.4 will flow [cm ³ / s]. So rather a trickle than a proper flow; Nevertheless, in a heating season a total of some m ^{3 of} water come together.

• (1.) Kontrollierte Entleerung eines Zwischenspeichers. Hierbei lässt man ein exakt definiertes Volumen innerhalb eines Sammelbehälters voll laufen, sorgt dann für eine automatische kurzzeitige Entleerung und zählt die Anzahl der Entleerungen. Diese Geräte funktionieren also vom Prinzip her, ähnlich wie Regen-Messgeräte.
• (2.) Wasseruhr mit vorgeschalteter Zwischenspeicherung. Ein Sammelbehälter wird periodisch entleert, wobei während der raschen Entleerung die Wassermenge mit einer konventionellen Wasseruhr registriert wird.

Such a trickle-water stream can be basically with two groups of devices measure up:

• (1.) Controlled emptying of a buffer. In doing so, a precisely defined volume within a collection container is allowed to run to full capacity, which then ensures automatic short-term emptying and counts the number of evacuations. So these devices work in principle, much like rain gauges.
• (2.) Water clock with upstream buffering. A collection container is emptied periodically, during the rapid emptying the amount of water is registered with a conventional water meter.

For precision measurements in high temporal resolution you can - so to speak as a generalized "water clock" - an electronic balance to register the amount of condensate between the periodic drains use (section 4.2.5). A similar effect, - however with much lower precision and temporal resolution - you get if you're at a big one Buffer (e.g., a "rain barrel") accurately calibrated level indicator used (section 4.1.2).

• • einfacher Wasserheber
• • doppelter Wasserheber, wobei der 2. Wasserheber als "Hauptleitung" einen größeren Leitungsquerschnitt besitzt und vom 1. Wasserheber ("Triggerleitung") eingeschaltet wird
• • aktivierter Wasserheber; hierbei füllt sich zunächst ein an einer Feder aufgehängtes kleines Aktivierungsgefäß, das durch sein wachsendes Gewicht nach unten gezogen wird und dadurch den angekoppelten eigentlichen Entleerungsschlauch aktiviert
• • Schwimmschalter steuern Ein- und Ausschalten von Magnetventil oder Pumpe
• • Ein Schwimmschalter mit Zeitdauergeber steuert Einschaltfenster von Magnetventil oder Pumpe
• • Wasserheber öffnet Einschalt-Zeitfenster von Magnetventil oder Pumpe

As a trigger for emptying several devices can be used:

• • simple water leveler
• • Double water leveler, where the second water leveler has a larger pipe cross-section as the "main line" and is switched on by the first water leveler ("trigger line")
• • activated water lift; In this case, first fills a hung on a spring small activation vessel, which is pulled by its growing weight down and thereby activates the coupled actual drain hose
• • Float switches control switching on and off of solenoid valve or pump
• • A float switch with timer activates switch-on window of solenoid valve or pump
• • Water lift opens switch-on time window of solenoid valve or pump

The actual emptying is either by gravity or by a pump driven.

Some this listed above Cases are in the following sections explained and some are also based on the patent claims - as far as she inventive height and not only for scientific purposes can be used.

4.1 type "controlled emptying "

4.1.1 Simple bucket method

At first there It's a trivial and free but a bit exhausting option for measuring the amount of condensate: Collect the condensed water. in a tub (I used a 90 l plastic tub from the construction sector) and empties them - usefully even before it overflows - with a "measuring bucket" (12 l or 20 l). With an additional small bucket (e.g., 5 liters) yourself the larger measuring bucket fill comfortably, The remaining amount is then dumped directly from the tub in the bucket. We recommend a certain amount of generosity in procurement of the measuring bucket: a level mark in liters he should already own and a 20 l bucket connects the service at the science with a dash of physical training.

Around To be sure, it is recommended that the measuring pails are not directly in to drain the drain, but the bucket-water first in to buffer a 500 l rain barrel. If this is then full is, you can see the volume with its records from the number Compare the bucket emptying and correct if necessary.

4.1.2 "Rainwater barrel" with level measurement

A more convenient variant of the bucket method [4.1.1] is achieved by that the Zwisehenspeicher "rain barrel" not by hand, but filled with a condensate water pump. Exceeds the water level a given emptying mark, the ton is deflated defined. The emptying of the "rain barrel" are now counted and the rest as well as the possible occurring supernatants on the emptying mark are littered. - On In any case, you should provide a proper safety overflow for an uncontrolled overflow to avoid. The easiest to handle is the safety overflow to use as a drain mark and the overflow in a smaller one Vessel that is just tell it off, temporarily.

is one at a big one temporal resolution Not interested in the measurement, you can see the overflow water of the last emptying period also just in the following period pour into the newly filling "rain barrel".

• • den Füllstandszeiger (Bild 1) als ein über die Wanddurchführung 104 außen an der Wand 100 der „Regentonne" von unten nach oben geführtes durchsichtiges Stück Schlauch oder Rohr 140, wobei die Volumen Markierungen 101 entsprechend der Gl.(36) (siehe unten) angebracht werden. Wer es auffälliger mag, kann auch einen Schwimmer mit Stab benutzen.
• • den Wasserheber entweder als einen oben durch die Außenwand der „Regentonne" wasserdicht geführten Schlauch oder als einen Schlauchbogen 142, der die Füllstandssäule 140 fortführt und durch eine am oberen Rand der Tonne sicher befestigten Halterung 149 fixiert wird. (zum Thema Wasserheber siehe auch Abschnitt 4.1.3)

This process can also be technically improved with little effort (Figure 1): The rain barrel can be a level indicator and an emptier 142 according to the water-lift principle (in analogy to Section 4.1.3 or even Section 4.1.4). Both devices can be quickly put together by DIY enthusiasts:

• • the filling level indicator (Fig. 1) as a through the wall duct 104 outside on the wall 100 the "rain barrel" from bottom to top led transparent piece of hose or pipe 140 , where the volume marks 101 according to equation (36) (see below). If you like it more conspicuous, you can also use a swimmer with a staff.
• • the water lifter either as a hose that is watertight at the top through the outer wall of the "rain barrel" or as a hose bend 142 , the level column 140 continues and by a securely attached to the upper edge of the bin holder 149 is fixed. (on the subject of water headers see also section 4.1.3)

A level indicator replaces a measurement with the meter. Rain barrels are usually built as a trapezoid, their volume is calculated from the mean diameter; for a lower inner diameter d ₁ and an upper inner diameter d ₂ and a total height h ₁₂ , therefore, the total volume V _ton arises to: V ton (H 12 ) = h 12 · Π / 4 · [(d 1 + (d 2 - d 1 ) / 2] 2 (35)

If the bin is filled only up to a filling level h, the filling volume V _ton (h) ZU results: V ton (h) = h · π / 4 · [(i.e. 1 + h / h 12 · (D 2 - d 1 ) / 2)] 2 (36)

at Metallic sewer pipes owns the caching of the Condensate water in a large volume Memory by the way nor the advantage that one does not persist his house internal sewer pipe but only occasionally and intermittently with the acid condensate water applied.

4.1.3 emptying by simple water jack

A more compact solution is provided by the simple water lift (Fig. 4). The condensate 1 runs over an inlet funnel 31 into a cache, the container 2 , This can be imagined, for example, as an upside-down bottle whose bottom is cut off and topped by a lid 3 is completed. The container 2 For example, it can be fixed to the wall next to the boiler with a pipe clamp; the enema 31 should be as high as possible to exploit a larger pressure gradient, - however, a safe reserve for the height of the condensate outlet within the boiler must remain. The two screws, which hold the pipe clamp laterally, can simultaneously serve as reference or anchor points for other components; For example, reducers, tees, hoses or hose connectors can be attached to them.

The container 2 So it runs slowly with the condensate water 1 full. The screw cap 21 but is from a suction line 4 broken through and the condensate 1 can via a supply line 40 and a reducer 41 into the trigger threshold 42 reach. This trigger threshold 42 consists of a spatially fixed arcuate tube piece with a not too large inner diameter. If the water 1 the highest point of the trigger threshold 42 has reached an additional water supply, the water front in this hose above the maximum (level line N4), the water jack turns on and the container 2 emptied via the outlet pipe 44 ,

When quickly draining the water 1 from the container 2 gets one on the lid 3 screwed on float switch 8th activates and sends a pulse to a counter 10 thereby registering the number of evacuations. Picture 5 shows the lid 3 with the float switch 8th in detail: When sinking the water sinks the float 80 down and close - before he gets his bottom stop lock 82 reached - an electrical contact, thereby giving a pulse to the counter 10 triggers. It is convenient the condensate inlet funnel 31 to be designed so that at the place of the float 80 no unnecessary "waves" are generated.

Figure 5 also shows one directly on the lid 3 attached displacement body 32 , which is located in the area of the level line N4, at which the trigger threshold 42 turns on. The displacement body 32 Increases the rate of increase in altitude of the water column in the area of the switching point (level line N4) of the trigger threshold 42 and thereby increases the sensitivity in triggering the water jack.

For the functioning of a water lift as an exact measuring instrument, it is very important that the water meniscus on the front side of the rising water column in the trigger line is also in the ever-horizontal part of the trigger threshold 42 preserved. Therefore, the inner diameter of the hose must be in the trigger threshold 42 be so small that the surface tension of the water still holds the meniscus together even at a standstill shortly before the upper vertex. For another inflow of condensate 1 If the rise of a water column, the pipe flow must be completely unproblematic, even if the level line N4 is exceeded and then drained. Will the inner diameter of the trigger threshold 42 viz. too large, it may happen that at low inflow the meniscus coincides and the water as a channel flow (ie without complete filling of the tube cross-section) on the level line N4 "torment" and then only as a channel flow or even in individual rivulets slowly expires. The most vicious case occurs when a channel flow in the drain prevents the trigger line from switching on and when the tank is full 2 always just as much water as trickle runs off as condensate tapers.

Tests with (transparent) PVC tubes of different diameters found that with an inner diameter of 6 mm, the tube flow was in the triggering threshold 42 is maintained and can maintain a compact meniscus at the water front even for many hours, if the water supply just before the switching point (level N4) of the trigger threshold 42 was stopped. (but see critical remark 7 in section 4.1.4)

Even with a diameter of 8 mm, however, the preservation of the pipe flow was no longer secured, although here also by some "dynamics" in the water supply (rapid inflow or slight movement of the water column) the pipe flow could save even when switching the trigger line. From this practical experience, the demand can be derived that the inner diameter of the trigger threshold 42 should not be larger than 6 mm. The suction line 4 and the supply line 40 can have a much larger diameter to reduce flow resistance.

A larger cross section in the drain line 44 On the other hand, it has not proven to be effective and only increases the risk that channel flows will form there, thereby reducing the height difference between level line N4 and the level line of the pressure equalization with the atmosphere (N0) that is effective for pressure development. - However, one could perhaps create a secure transition to a larger flow cross section by stabilizing the transition.

4.1.4 emptying by triggered double water lifter

The condensate, which during the emptying time of the container 2 is counted, is not taken into account by the counting process. The emptying time thus represents a dead time for the measurement. Therefore, measures should be taken to accelerate the process. Of course it is good by the drain line 44 exploit the greatest possible height difference, but this is limited by the local conditions.

Another way to reduce the dead time is a second line for emptying the container 2 consulted. However, a simple parallel connection would only be possible if both lines were switched through at exactly the same time. When switching through the first line namely reduces the pressure in the second line and the latter is usually at most at high inflow still to the train.

Figure 6 shows a triggered double water lift. This is a device in which switching the trigger threshold 42 on the level line N4 switching through a 2nd line, the "main line" 50 - 54 , about the level higher level N5 causes. The device is an extension of the simple water lifter according to Figure 4 through the additional main line 50 - 54 standing at the tee 5 from the intake pipe 4 and the trigger line 40 - 44 branches.

It should be noted that the spout 59 the main pipe inside a water-filled spout connector 9 is located and thus has no direct contact with the ambient air. The outlet connector 9 is either filled with water from the last emptying or it is at the beginning of the emptying process through the trigger line 40 - 44 that have a tee 46 also in the outlet connector 9 flows, filled.

The essential functional element for switching through the main line is in the pressure equalization line 6 connecting the trigger line to the main line via a T-piece 43 respectively. 53 combines. When the trigger line is switched through, it flows through the T-piece 43 a water flow down, according to the principle of a water jet pump air from the still anhydrous part of the switching threshold 52 and from the drain line 54 the main sucks. This reduces the pressure there and the water column is in the switching threshold 52 lifted and - if properly designed - pulled over the level line N5 and then flows through the drain line 54 from. This process takes place dynamically and therefore the pipe flow is maintained even with a larger pipe cross-section. In a test setup, a 10 mm inner diameter main line was successfully used.

• 1. die Druckausgleichsleitung 6 sollte einigermaßen waagrecht verlaufen und einen geringen Querschnitt aufweisen. Ich benutzte in meinem Versuchsaufbau einen Schlauch mit 6 mm innerem Durchmesser, in den wiederum ein Schlauch mit 3 mm innerem Durchmesser eingeschoben war. D.h. die Verschaltung erfolgte auf der 6 mm Ebene, der wirksame Durchmesser betrug jedoch nur 3 mm.
• 2. Der Auslauf-Verbinder 9 sollte kompakt sein, damit eine Erstbefüllung über die Triggerleitung 40 – 44 rasch und ohne spürbaren Druckabfall erfolgen kann. Ich benutzte ein 19 mm -T-Stück mit zwei über kurze Schlauchstücke eng angeflanschten 90 Grad Winkelstücken (Bild 7). Die zur Verbindung benutzten Enden wurden durch Absägen in ihrer Länge etwa halbiert. Es ergibt sich dadurch ein kompakter Körper mit 3 parallelen Zugangsleitungen. Die Ablaufleitung 54 der Hauptleitung wurde in die linke Randleitung 91 und die Triggerleitung 44 mit dem Auslauf-T-Stück 46 in die mittlere Leitung 92 eingeführt; hierbei wurde darauf geachtet, dass die waagrechte Öffnung des Auslauf-T-Stückes 46 eine freie Verbindung zur Außenluft behält. Die rechte Randleitung 93 wurde etwas gekürzt, wobei allerdings die Wasserbedeckung des Auslaufes garantiert blieb, und als Abflussleitung benutzt.
• 3. Der Abstand der Niveaulinien N4 und N5, also die Höhendifferenz der Schaltpunkte zwischen den Schwellen 42 und 52, soll möglichst gering sein, damit die "Wasserstrahlpumpe" nur einen kleinen Unterdruck erzeugen muss, In meinem Ver suchsaufbau benutzte ich als Behälter 2 eine Kunsstoffflasche und führte die Triggerschwelle 42 als Schlauchschleife vor der Flasche und die Schaltschwelle 52 äls Schlauchschleife hinter der Flasche vorbei. Dadurch wird eine räumliche Beeinflussung der Schläuche vermieden und die Niveaulinien N4 und N5 lassen sich sehr genau einstellen. Es muss jedoch garantiert bleiben, dass die Triggerschwelle 42 zuerst anspringt, da nur bei ihr der Durchmesser (mit 6 mm) so gewählt wurde, dass auch bei extrem langsamem Zulauf die Rohrströmung gewahrt bleibt.
• 4. Die gemeinsame Ansaugleitung 4, die über das T-Stück 5 sowohl die Triggerleitung 40 – 44 als auch die Hauptleitung 50 – 54 speist, ist natürlich nur äußerlich elegant. Beim Durchschalten der Triggerleitung ergibt sich durch die Wasserströmung im T-Stück 5 natürlich auch ein unerwünschter ("böser") Wasserstrahlpumpen Effekt, der den Druck in der Hauptleitung 50 – 52 verringert. Die über das T-Stück 43 wirkende "gute" Wasserstrahlpumpe muss also nicht nur die Druckdifferenz zwischen den Niveaulinien N4 und N5 sondern auch den Gegendruck der "bösen" Wasserstrahlpumpe (T-Stück 5) überwinden. Um diesen Gegendruck zu minimieren muss der Querschnitt der Ansaugleitung 4 und vor allem des T-Stückes 5 möglichst groß sein, so dass sich in der "bösen Wasserstrahlpumpe" (T-Stück 5) eine wesentlich kleinere Stömungsgeschwindigkeit als in der "guten Wasserstrahlpumpe" (T-Stück 43) ergibt. In meinem Versuchsaufbau benutzte ich ein 19-mm T-Stück 5, das mit dem senkrechten Ende durch den Schraubverschluss 21 hindurch in den Behälter 2 (eine Flasche) hineinragte. Trotzdem konnte man zu Beginn des Schaltvorganges zunächst ein leichtes Absinken der Flüssigkeitssäule in der Schwelle 52 der Hauptleitung bemerken. Der Durchmesser des T-Stückes 5 war jedoch durch den Durchmesser des Schraubverschlusses 21 begrenzt.
• 5. Eine Alternative zur gemeinsamen Ansaugleitung 4 besteht übrigens darin, dass man die Hauptleitung nicht über das T-Stück 5 speist, sondern sie in einer gesonderten Leitung von oben durch den Deckel 3 hindurch in den Behälter 2 einführt (Bild 8). Das untere Ende dieses Ansaug-Rüssels 5a, welcher eine zur Ansaugleitung 4 analoge gesonderte Ansaugleitung für die Hauptleitung 50 – 54 darstellt, sollte etwa auf gleichem Niveau wie die Mündung der Ansaugleitung 4a für die Triggerleitung 40 – 44 oder ein klein wenig darunter liegen. Diese Version mit getrennten Ansaugleitungen ist zwar durchaus brauchbar, aber die Menge des nach dem Absaugvorgang im Behälter und den Leitungen verbleibenden Restwassers ist nicht ganz so gut reproduzierbar wie bei der bevorzugten Version nach Bild 6. (In Bild 8 wurde übrigens der Übersichtlichkeit halber die sonstige Beschattung des Deckels 3 weggelassen).
• 6. Die die Strömung in der Triggerleitung antreibende Höhendifferenz zwischen Triggerschwelle (Niveaulinie N4) und dem Luftzutritt am Auslauf der Triggerleitung (Niveaulinie N0 am T-Stück 46), ist etwas kritisch. Die sich ergebende Druckdifferenz muss groß genug sein, um die Wassersäule in der Hauptleitung mit einem kleinen Schwung über die Niveaulinie N5 zu heben, so dass die Rohrströmung auch bei einem größeren Querschnitt erhalten bleibt, bzw. sich nach Beendigung der Luftabsaugung voll ausbildet. In meinem Versuchsaufbau arbeitete ich mit einer Höhendifferenz von 70 cm (also: N4 – N0 = 70 cm), was gerade ausreichte.
• 7. In meinem Versuchsaufbau benutze ich preiswerte Schläuche („PVC-glasklar)". Es zeigte sich jedoch, dass diese sich bei längerem Betrieb an der inneren Oberfläche so veränderten, dass die Rohrströmung immer leichter in eine Gerinneströmung umkippte. Die Rohrströmung ließ sich bisher durch eine größere antreibende Höhendifferenz (z.B. N4 – N0 = 85 cm) stabilisieren. Eine Verringerung der inneren Durchmesser der Schläuche dürfte ebenfalls stabilisieren – allerdings auf Kosten der Leistungsfähigkeit. Ich hoffe, dass sich das Problem mit geeigneterem Schlauchmaterial für die Triggerschwelle (42) und für die Schaltschwelle (52) beheben lässt. Schlimmstenfalls müssten diese Teile öfters erneuert werden.

Some comments on the construction and design of the triggered water lifter:

• 1. the pressure equalization line 6 should be reasonably horizontal and have a small cross-section. In my experimental setup, I used a 6 mm inner diameter tube with a 3 mm inner diameter tube inserted into it. This means that the connection was made on the 6 mm level, but the effective diameter was only 3 mm.
• 2. The outlet connector 9 should be compact, so that a first filling via the trigger line 40 - 44 can be done quickly and without noticeable pressure drop. I used a 19mm T-piece with two 90 degree elbows closely flanged over short lengths of tubing (Figure 7). The ends used for connection were approximately halved by sawing in their length. This results in a compact body with 3 parallel access lines. The drain line 54 the main line became the left edge line 91 and the trigger line 44 with the spout tee 46 in the middle line 92 introduced; Care was taken to ensure that the horizontal opening of the outlet tee 46 maintains a free connection to the outside air. The right edge line 93 was slightly shortened, although the water cover of the spout was guaranteed, and used as a drain pipe.
• 3. The distance between the level lines N4 and N5, ie the height difference of the switching points between the thresholds 42 and 52 , should be as low as possible, so that the "water jet pump" only has to generate a small negative pressure. In my experimental setup, I used as a container 2 a Kunsstoffflasche and led the trigger threshold 42 as a hose loop in front of the bottle and the switching threshold 52 äls hose loop past the bottle. This avoids a spatial influence on the hoses and the level lines N4 and N5 can be set very accurately. However, it must be guaranteed that the trigger threshold 42 first starts, because only with her the diameter (with 6 mm) was chosen so that even with extremely slow inflow the pipe flow is maintained.
• 4. The common intake pipe 4 that over the tee 5 both the trigger line 40 - 44 as well as the main line 50 - 54 of course, is only outwardly elegant. When the trigger line is switched on, this is due to the water flow in the T-piece 5 Of course, also an undesirable ("bad") water jet pumping effect, the pressure in the main line 50 - 52 reduced. The over the tee 43 acting "good" water jet pump must therefore not only the pressure difference between the level lines N4 and N5 but also the back pressure of the "evil" water jet pump (T-piece 5 ) overcome. To minimize this back pressure, the cross-section of the suction line must be 4 and especially the tee 5 be as large as possible, so that in the "evil water jet pump" (T-piece 5 ) a much smaller flow rate than in the "good water jet pump" (T-piece 43 ). In my experiment setup, I used a 19-mm tee 5 with the vertical end through the screw cap 21 through into the container 2 (a bottle) protruded. Nevertheless, you could at the beginning of the switching process, first a slight drop in the liquid column in the threshold 52 notice the main. The diameter of the tee 5 was, however, by the diameter of the screw cap 21 limited.
• 5. An alternative to the common intake pipe 4 Incidentally, the main thing is that you do not have the main line over the tee 5 feeds it but in a separate line from the top through the lid 3 through into the container 2 introduces (Fig. 8). The lower end of this intake snout 5a , which one to the suction line 4 analogue separate suction line for the main line 50 - 54 should be about the same level as the mouth of the intake pipe 4a for the trigger line 40 - 44 or a little bit lower. Although this version with separate suction lines is quite useful, but the amount of remaining after the suction in the container and the lines of residual water is not quite as good reproducible as in the preferred version of Figure 6. (Figure 8 was the way, for the sake of clarity, the other Shading the lid 3 ) Omitted.
• 6. The height difference between the trigger threshold (level line N4) and the air inlet at the outlet of the trigger line that drives the flow in the trigger line (level line N0 on the T piece 46 ), is something critical. The resulting pressure difference must be large enough to lift the water column in the main line with a small sweep across the level line N5, so that the pipe flow even at a size ren cross section is maintained, or fully formed after completion of the air extraction. In my experiment setup, I worked with a height difference of 70 cm (ie: N4 - N0 = 70 cm), which was just enough.
• 7. In my experimental set-up, I use inexpensive tubing ("PVC-clear"), but it turned out that they changed on prolonged operation on the inner surface so that the pipe flow tipped more and more easily into a channel flow stabilize by a larger driving height difference (eg N4 - N0 = 85 cm) A reduction of the inner diameter of the hoses should also stabilize - but at the expense of the performance I hope the problem with more suitable tubing for the trigger threshold ( 42 ) and for the switching threshold ( 52 ). In the worst case, these parts would have to be renewed more often.

4.1.5 emptying by activated water lift

The Although previous water-lifting methods are simple, they are one huge Diameter of the storage vessel and associated with this very slow increase in level height one would like Be sure that there is no "malignant" channel flow Switching through the pipe flow delay or even prevent it. The problem would be solved, if there was a mechanism when reaching the nominal filling level N4 in Storage vessel, the switching threshold of the drainage water jack well below the level of the reservoir depressing. If then the pipe flow in the evacuation tube once got started correctly the switching threshold again go up and before the beginning of the subsequent refilling of the storage container sure about the target level height N4 remain.

Such an activation mechanism, the switching threshold of the discharge hose 142 is pressed down, is shown in Figure 2 and Figure 3. When the nominal fill level N4 in the storage vessel is reached 2a First, water runs over the activation line 152 - 154 on the principle of the water lift from the store 2a in an activation vessel 155 , The activation hose consists of a first part 152 standing in the interior of the storage vessel 2a located, and a second section 154 which is located in its exterior space; both sections meet in a wall passage 153 , through which the nominal fill level N4 of the memory 2a is fixed. The inside hose piece 152 ensures that the activation line still functions as a water jack when the level in the storage vessel has dropped again slightly below the setpoint level N4.

• 1. es ist über eine mechanischen Feder 150 an einer mit dem Speichergefäß 2a starr verbundenen Feder-Haltevorrichtung 151 befestigt
• 2. es besitzt seinerseits eine Haltevorrichtung 156, welche als Scheitelpunkt für den Entleerungs-Schlauch 142 dient, der nach dem Prinzip des Wasserhebers über die Füllstandssäule 140 und den Wanddurchgang 104 mit dem unteren Teil des Speichergefäßes 2a verbunden ist,

The activation vessel 155 is characterized by two peculiarities:

• 1. It is about a mechanical spring 150 at one with the storage vessel 2a rigidly connected spring-holding device 151 fixed
• 2. It in turn has a holding device 156 , which serves as the vertex for the drain hose 142 serves, according to the principle of the water lifter on the level column 140 and the wall passage 104 with the lower part of the storage vessel 2a connected is,

If now after reaching the target level N4 the activation vessel 155 filled with water, so its increasing weight stretches its suspension spring 150 and it shifts itself down. During this downward movement, the coupled holding device presses 156 the drain hose 142 further down and finally well below the water level in the storage vessel 2a , In the, usually after an initial channel flow, the pipe flow switches, - the ascending branch of the discharge hose 142 is completely filled -, through and takes over an efficient emptying of the storage container 2a ,

After a short time, the water levels in the storage tank 2a and in the activation vessel 155 balanced. When passing through the drain hose 140 - 144 carried further emptying, however, the level continues to fall down; then water runs out of the activation vessel 155 back to the storage vessel 2a , This will cause the activation vessel 155 lighter and the contracting spring pulls the activation vessel 155 Now up until it (and also the connecting hose 154 ) completely drained and the water connection to the storage vessel 2a demolished. The device must be dimensioned so that the holding device 156 is then significantly above the nominal filling level N4.

Another increase in the level in the storage tank 2a has then on the activation vessel 155 no influence until the nominal level N4 is reached again and the above activation mechanism with the filling of the activation tank 155 lowering the threshold 156 for the drain hose 142 , the switching of the pipe flow in the drain hose 142 etc. starts over again.

The float switch required to register the draining operations 8th that counts the counts of the counter 10 can trigger conveniently in the activation vessel 155 be attached.

The storage vessel 2a may be part of a neutralization device.

As a storage vessel 2a very different tanks can be used: from the rain barrel to the water bucket; yes with miniaturization of the activation vessel 155 and a very elastic drain hose piece 142 you can even use even smaller containers. For the mobile meter of an energy consultant, for example, would be a 20 l bucket as a storage container 2a suitable, which is placed on a height-adjustable stool so near the fireplace, that the gap between the outlet of the condensate hose at the siphon of the burner and the drain pipe into the sewer is exploited for the largest possible stroke. In favorable local conditions, the storage vessel can also be placed under the (on the wall hanging) fireplace, in unfavorable conditions, however, a pump must be used. The measuring bucket can be used without any intervention in the combustion or heating system: The existing condensate hose of the burner is inserted into the measuring device and the drainage hose 144 of the storage vessel 2a plugged into the duct connection.

4.1.6 Solenoid valve switches emptying

In confined spaces, emptying can also be achieved by opening a solenoid valve 77 at the outlet of the storage tank 2 effect (Figure 9). Reach the float 80 of the float switch 85 an upper switching point 86 so will the solenoid valve 77 opened, at a lower switching point 87 the solenoid valve is closed again. Instead of the floating switch shown in fig 85 Of course, with two switching points, two separate float switches, each with one switching point, can also be used in practice.

An emptying is done by another float switch 8th (in figure 9 only indicated, see if necessary picture 5) detected and from the counter 10 registered.

4.1.7 Counter registered Emptying the condensate pump

• • jeweils eine reproduzierbare und ausreichend empfindliche Schaltschwelle ((86), (87)) für das Einschalten und für das Ausschalten der Pumpe festlegen, und dabei das dadurch definierte Speichervolumen im Speicherbehälter 25 möglichst so wählen, dass sich ein runder Betrag (z.B. 1,0 Liter) oder ein griffiger Referenzbetrag ergibt. (Ein solcher Referenzbetrag wäre beispielsweise das Volumen der maximalen theoretischen Kondensatmenge die beim Verbrennen von 1 m³ Erdgas erzeugt wird, also z.B. 1,6 Liter). Die Empfindlichkeit lässt sich durch eine räumliche Einengung im Höhenbereich der Schaltschwellen, – vergleiche hierzu in Bild 5 den Verdrängungskörper 32 im Höhenbereich der Niveaulinie N4 der Schaltschwelle – steigern.
• • den Pumpvorgang, während dessen ja die Messung ausgeblendet ist, so rasch wie möglich erledigen, insbesondere darf man keine Nachlaufzeiten erlauben.
• • praktischerweise einen gesonderten Schwimmschalter 8 für das Auslösen eines Zählschrittes installieren. Im Prinzip könnte man auch einen der vorhandenen Schwimmschalter hierfür mitbenutzen, allerdings ist eine galvanische Trennung zwischen dem Zählereingang und dem Arbeitsstrom der Pumpe wohl sinnvoll.
• • einen Zähler 10 zur Registrierung der Anzahl der Entleerungen installieren

A condensate pump 75 usually only jumps after filling a storage tank 25 by triggering a float switch 85 and then sucks on a suction line 76 the accumulated condensate 1 in a short-term condensate stream 1a from. This process can be used and the number of discrete discharges by a counter 10 register (Figure 10). However, you have to modify a conventional condensate pumping system, which was previously not intended for this purpose something. You have to:

• • in each case a reproducible and sufficiently sensitive switching threshold (( 86 ) 87 )) for switching on and switching off the pump, and thereby the storage volume defined in the storage tank 25 if possible, choose a round amount (eg 1.0 liter) or a handy reference amount. (Such a reference amount would be, for example, the volume of the maximum theoretical condensate amount that is generated when burning 1 m ^{3 of} natural gas, for example, 1.6 liters). The sensitivity can be determined by a spatial constriction in the height range of the switching thresholds, - compare in Figure 5 the displacement body 32 in the height range of the level line N4 of the switching threshold - increase.
• • Do the pumping, during which the measurement is hidden, as quickly as possible, in particular, you must not allow any delay times.
• • conveniently a separate float switch 8th for triggering a counting step. In principle, you could also use one of the existing float switch for this, but a galvanic isolation between the counter input and the working current of the pump is well meaningful.
• • a counter 10 to register for the number of drains to install

4.2 Type "Water Clock"

• • 4.2.1 Man setze vor die Wasseruhr 7 einen Sammelbehälter 25 als Zwischenspeicher und entleert diesen mittels Pumpe 75 (Bild 11), wobei der Pumptakt durch einen Schwimmer 85 oder dergleichen gesteuert wird. „Kondensatpumpen" nach diesem Prinzip sind handelsüblich, sie müssen nur noch durch eine für das sauere Kondensatwasser geeignete Wasseruhr 7 ergänzt werden. In den Einlauftrichter 31 tritt also kontinuierlich "tröpfelndes" Kondensat 1 ein bis der Speicherbehälter 25 so weit gefüllt ist, dass die Kondensatpumpe 75 einschaltet. Diese entleert dann über die Ansaugleitung 76 den Behälter mit einem Wasserstrom 1a, der groß genug ist, die Wasseruhr 7 ordnungsgemäß zu betreiben. Durch die Wasseruhr 7 wird auch dasjenige Kondensatwasser gemessen, das während der Entleerung in den Behälter einläuft. Daher braucht eine gegebene Kondensatpumpe normalerweise nicht verändert zu werden.
• • 4.2.2 Man nimmt im Speicherbehälter 25 eine Neutralisierung des saueren Kondensates 1 vor; dann kann man eine gewöhnliche, für Trinkwasser eingesetzte Wasseruhr benutzen. Kondensatpumpen mit vorgeschalteter Neutralisierung sind ebenfalls im Handel erhältlich. Die Neutralisierung schont hierbei dann nicht nur die Pumpe und die häusliche und städtische Abwasserleitung sondern noch zusätzlich die Wasseruhr
• • 4.2.3 Man versieht einen Zwischenspeicher mit einer nicht notwendigerweise sehr exakt definierten Schwelle bei deren Überschreitung eine Entleerung ausgelöst wird und die Entleerungsmenge durch eine Wasseruhr gemessen wird. Diese Wasseruhr-Methode kommt also ohne Kondensatpumpe aus. Als Schwelle kann beispielsweise die Schaltschwelle 42 (Niveaulinie N4) eines einfachen oder getriggerten doppelten Wasserhebers (Bild 12 bzw. Bild 13) dienen; dann ist allerdings ein ausreichender Höhenunterschied zwischen Kondensateinlauf und dem Kondensatablauf in die Kanalisation erforderlich. Bei dem getriggerten doppelten Wasserheber (Bild 13) muss die Wasseruhr 7 natürlich in eine gemeinsame Leitung wie beispielsweise in die Ansaugleitung 4 eingefügt werden, in der die Wasserströme der Triggerleitung 40 – 44 und der Hauptleitung 50 – 54 noch gemeinsam geführt werden
• • 4.2.4 Bei beengten Platzverhältnissen können statt eines Wasserhebers auch Schwimmschalter (oder ein einziger. Schwimmschalter mit Timer) eingesetzt werden, die den Ablaufstrom über ein Magnetventil ein- und wieder ausschalten (Bild 14).

If a water meter is to show exact values, the water flow to be measured must exceed a minimum value. This requirement can be met by various circuits:

• • 4.2.1 Put in front of the water clock 7 a collection container 25 as a buffer and empties it by means of a pump 75 (Figure 11), where the pumping stroke by a float 85 or the like is controlled. "Condensate pumps" according to this principle are commercially available, they only need a suitable for the acid condensate water meter 7 be supplemented. In the inlet funnel 31 So come on Quite "trickling" condensate 1 one to the storage tank 25 filled so far that the condensate pump 75 turns. This then empties through the intake pipe 76 the container with a stream of water 1a big enough, the water clock 7 to operate properly. Through the water clock 7 Also the condensate water is measured, which enters the container during emptying. Therefore, a given condensate pump normally does not need to be changed.
• • 4.2.2 Take in the storage tank 25 a neutralization of the acidic condensate 1 in front; then you can use a normal, used for drinking water meter. Condensate pumps with upstream neutralization are also commercially available. The neutralization protects not only the pump and the domestic and municipal sewer but also the water meter
• • 4.2.3 It provides a buffer with a not necessarily very precisely defined threshold above which emptying is triggered and the emptying amount is measured by a water meter. This water meter method is therefore without condensate pump. As a threshold, for example, the switching threshold 42 (Level line N4) of a simple or triggered double water lift (Fig. 12 or Fig. 13); then, however, a sufficient difference in height between the condensate inlet and the condensate drain into the sewage system is required. For the triggered double water lift (Fig. 13), the water meter must be turned on 7 course in a common line such as in the intake 4 be inserted, in which the water flows of the trigger line 40 - 44 and the main line 50 - 54 still be led together
• • 4.2.4 Where space is at a premium, float switches (or a single float switch with timer) can be used instead of a water lift, which switch the drainage current on and off via a solenoid valve (Figure 14).

• 4.2.5 Precision method with balance or level sensor

• • 4.2.5 Precision method with scale or level sensor If, for example, you want to perform an exact condensate measurement in high temporal resolution, for example for research purposes, it seems to be advantageous to use the condensate together with the buffer 2 (or 25 ) on a suitable electronic balance and to register the current weight time-dependent. (See also the method in DIN 4702 Part 2/10 /). At an upper switching point, the buffer is then emptied quickly (see eg section 4.1.4 or section 4.2.4) and the weighing process is continued at a lower level. In our system, this weighing method is a combination of a kind of "water clock method" for high temporal resolution and long-term emptying method. The current water content of a larger storage tank 2a can also be measured with a level sensor. Although this method is not quite as accurate as weighing, there is also an electronic signal with high temporal resolution that is sufficiently accurate for many purposes.

5. Direct electronic determination of exhaust gas losses

• 5.1 The most straightforward way to determine the exhaust gas losses for a certain period of time t ₀ is to: 1. measure the CO2 content of the exhaust gas, remember the value measured by the heating service or the chimney sweep, or set the setting value of [CO2 2. read the quantity W of condensate water, 3. read off the associated gas consumption at the gas meter and from the gas volume V _G according to equation (11b) or from the associated firing heat quantity Q _F according to equation (11a ) determine the theoretically possible maximum water quantity WD ₀ 4. calculate the mean condensate fraction w from W and WD ₀ according to equation (11). 5. calculate the dew-point temperature T belonging to w T _{dew point} (w) according to equation (15) to equation (18) or read from a graph or a table of values. 6. and finally from these quantities according to equation (33) (or equation (33a)) in conjunction with equation (32) calculate the net exhaust gas loss.

The count signals the water meter or the trigger signals for emptying the measuring volume can together with a count signal the gas meter are processed electronically. This can be done directly calculate the net exhaust gas loss electronically and can a display. The electronic processing This is not more expensive than about a "bike computer" as a mass-produced at a unit price of less than 10 euros.

• – Wenn die vorhandene Gasuhr einen elektrischen Ausgang besitz oder sich ein solcher einfach nachrüsten lässt, dann ergibt sich hieraus kein besonderes Problem.
• – Falls sich die Gasuhr nicht als elektronischer Signalgeber heranziehen lässt, muss. man sich ein Hilfssignal für Q_F besorgen: Bei modulierenden Gasbrennern wird eine Einstell- und Messgröße für Q_F benötigt, um die Verbrennungsluftzufuhr an die schwankende Brennerleistung anzupassen. Dies geschieht beispielsweise durch einen Differenzdrucksensor an der Gaszuleitung zum Brenner. Dieses Signal kann vermutlich auch zur digitalen Berechnung von Q_F herangezogen werden. Bei einer Ein- Aus Regelung mit fest eingestelltem Brenner mit konstanter Heizleistung Q_F' genügt ein Betriebsstunden Zähler, da QF = QF'·tB, (37)wobei t_B die Anzahl der Betriebsstunden bezeichnet.
• – Im unglücklichen Falle, dass sich weder aus der Gasuhr noch aus der Brennereinheit eine Signalgröße für Q_F erhalten lässt, verbleibt als Ausweg, die vom Heizwasser und vom Warmwasser aufgenommene Wärme, Q_WW, mit einem (oder zwei) Wärmemengenzähler zu messen. Die auf den Brennwert H_o bezogene Feuerungswärme Q_F,ob lässt sich nämlich darstellen als Summe von der vom Wasser aufgenommenen Wärme Q_WW (vom Wärmemengenzähler erfasst) der Bruttoabgaswärme, Q_{Abg_brutto}, und der vom Wärmeerzeuger an den Aufstellungsort abgestrahlten Wärme Q_Strahlung Also: QF,ob = QWW + QAbg_brutto + QStrahlung (38) Die Strahlungswärme Q_Strahlung ist bei einem modernen Kessel sehr klein und kann daher in (38) entweder vernachlässigt werden oder nur mit einem globalen "Merkposten" von beispielsweise 0,01·Q_F berücksichtigt werden. Dann lässt sich die auf den Brennwert H_o bezogene ("obere") Feuerungswärme Q_F,ob aus den beiden Messgrößen Q_WW und Q_{Abg_brutto} bestimmen. Da das Verhältnis des oberen Heizwertes, des Brennwertes H_o, zum (unteren) Heizwert H_u für jeden Brenstoff bekannt ist, lässt sich Q_F ermitteln aus: QF = QF,ob·Hu/Ho (39)Falls nur die Nettoabgaswärme Q_Abg gemessen wird muss man aus derselben die Bruttoabgaswärme Q_Abg brutto für Gl.(38) abschätzen. Bei gut eingestellten Brennwertgeräten ist der Unterschied (Q_{Abg_brutt}o – Q_Abg)/Q_F nur wenige Prozentpunkte, also geringfügig.

• 5.2 Oft mag es auch interessant sein, auf eine detaillierte Berechnung der Abgasverluste zu verzichten und dafür eine anschauliche und leicht bestimmbare Kenngröße heranzuziehen. Hierfür geeignet ist das spezifische Kondensataufkommen x_V xV = W/VG = "Liter Kondensat pro m3 Gas", (40)welches man mit seinem theoretischen maximalen Wert, x_V0 = 1,6 Liter Wasser pro m³ Erdgas (siehe Gl.(11b)), vergleichen kann. Dieses Verhältnis ist identisch mit dem in Gl.(11) definierten Kondensatanteil w, wie man durch Einsetzen sofort erkennen kann: xV/xV0 = (W/VG)·(VG/WD0) = W/WD0 = w,also w = xV/xV0 = xV/1,6 für Erdgas (41)

However, the task initially arises, an electronic signal for fuel consumption and thus, indirectly for Q _F to be obtained. Depending on the system, this can be easy or a little more complicated:

• - If the existing gas meter has an electrical outlet or such an easy retrofit, then this does not give rise to any particular problem.
• - If the gas meter can not be used as an electronic signal generator, must. To get an auxiliary signal for Q _F : In modulating gas burners, a set and measured variable for Q _{F is} required to adjust the combustion air supply to the fluctuating burner power. This is done for example by a differential pressure sensor on the gas supply line to the burner. This signal can probably also be used for the digital calculation of Q _F. In an on-off control with permanently set burner with constant heat output Q _F 'is sufficient for an operating hours counter, since Q F = Q F '* T B , (37) where t _B denotes the number of operating hours.
• - In the unfortunate event that a signal magnitude for Q _F can not be obtained from either the gas meter or the burner unit, the solution is to measure the heat absorbed by the heating water and hot water, Q _WW , with one (or two) heat meters. The object relating to the calorific value H _o rated thermal Q _{F, if} can be represented as the sum of the recorded from the water heat Q _WW (detected by the calorimeter) of gross exhaust heat Q _{Abg_brutto,} and radiated from the heat generator to the site of heat Q _radiation So namely: Q F if = Q WW + Q Abg_brutto + Q radiation (38) The radiant heat Q _radiation is very small in a modern boiler and therefore can either be neglected in (38) or taken into account only with a global "flag" of, for example, 0.01 * Q _F. Then it is possible to determine the ("upper") combustion heat Q _F, based on the calorific value H _{o , whether} from the two measured variables Q _WW and Q _{Abg_brutto} . Since the ratio of the upper heating value, the calorific value H _o , to the (lower) calorific value H _u for each fuel is known, Q _F can be determined from: Q F = Q F if ·H u /H O (39) If measured, only the net exhaust heat Q _Abg will have to estimate the gross exhaust heat Q _Abg gross for Eq. (38) therefrom. With well-adjusted condensing _appliances , the difference (Q _{Abg_brutt} o - Q _Abg ) / Q _{F is} only a few percentage points, ie slight.

• 5.2 Often it may be interesting to dispense with a detailed calculation of the exhaust gas losses and to use a descriptive and easily determinable characteristic. Suitable for this purpose is the specific condensate volume x _V x V = W / V G = "Liters of condensate per m 3 Gas ", (40) which can be compared with its theoretical maximum value, x _V0 = 1.6 liters of water per m ^{3 of} natural gas (see equation (11b)). This ratio is identical to the condensate fraction w defined in equation (11), as can be seen immediately by insertion: x V / x V0 = (W / V G ) * (V G / W D0 ) = W / W D0 = w, so w = x V / x V0 = x V / 1.6 for natural gas (41)

wobei für (Q_WD0/Q_F) in Gl.(33a) für Erdgas etwa 11 % eingesetzt wurde (siehe Gl.(14)).Now you can already exactly determine the part of the exhaust gas loss, which is due to the unused latent heat of the remaining water vapor in the exhaust gas (see the 2nd term in Eq. (33a))

approximately 11% was used for (Q _WD0 / Q _F ) in equation (33a) for natural gas (see equation (14)).

eine erstaunlich gute Annäherung an die Gl.(33a) erreichen: der Fehler liegt im angegebenen Bereich immer unter 0,3 Prozentpunkten, in den meisten Fällen sogar deutlich darunter. Außerhalb des angegebenen Bereiches kann die Formel (43) mit einem etwas modifizierten Maximalwert anstelle der angegeben 13,5 % angepasst werden.For the first term in Eq. (33a), one should also give a simple function of (1-w), if only as a rule of thumb. Assuming a cellar temperature of 15 ° C, a CO2 content of the exhaust gas in the range of about 4-11% and a condensate content w in the range 0.3 to 0.9 and decreases for large values of w a larger relative error out, so you can for the entire exhaust loss q _Abg with the rule of thumb

Achieve an astonishingly good approximation to Equation (33a): the error in the given range is always below 0.3 percentage points, in most cases even significantly lower. Outside the specified range, formula (43) can be adjusted with a slightly modified maximum value instead of the specified 13.5%.

An electronic display for the amount of condensate W, which can be synchronized by a reset with the start value for the reading of the gas meter, is actually already sufficient, according to the Gln. (40) to (42) to determine the most prevalent latent exhaust gas loss q _{Abg, latent} exact and the total net exhaust gas loss according to equation (43) as a rule of thumb q _Abg .

6. Advantages of the procedure

The essential advantages of the condensate process can be summarized as follows:

Correct measurement

• 1. The measurement error is low because the net exhaust gas loss over the Condensate quantity is measured directly and not as a difference of two formed by about a factor of 10 larger quantities must be - how this is the case with alternative measuring methods.
• 2. The measuring method is integrating, i. the net exhaust gas loss can be over as an average measured smaller or larger periods become.

decision relevant measurand

• 3. The measurand, the net exhaust gas loss, shows reliable the potential for Further savings can therefore be used as a benchmark for the profitability of investments serve. In contrast, the measured according to the 1.BlmSchV Gross exhaust gas loss the fireplace heat and therefore overestimates systematically the savings potential.
• 4. The fireplace heat can be measured separately and directly. This may be the stubborn deniers convince under the bestallte professionals that only the net exhaust gas loss correctly specifying the savings potential.

Simple, descriptive, decentralized

• 5. The measurement effort is low. Simple versions (e.g., the waterlift devices) can be made by any DIY enthusiast become. There are even primitive but practically free Methods (e.g., bucket emptying or level measurement in a "rain barrel" as a large cache) to disposal.
• 6. The measured variable is clear: The amount of condensed water directly shows the heat gain Condensation of the combustion water, otherwise through the chimney uselessly dissipated would.
• 7. The measuring method can be used by the operator independently become; an external expert and expensive measuring instruments are - in contrast to the chimney sweep measurement after the 1st BlmSchV - not required. There are even primitive but practically free Methods (e.g., bucket emptying or level measurement in a "rain barrel" according to section 4.1.1 and Section 4.1.2).

Both for measuring campaign as well as standard accessories

• 8. A measuring device can be retrofitted next to the boiler. An intervention in the boiler is not required, since the condensate is already standard in a hose to the outside to be led. An intervention in the heating circuit is not required.
• 9. A measuring device can also be used directly in the boiler be integrated and the measured variable, for example via the Control unit of the boiler are retrieved. By conversion of the siphon for the condensate as storage tank (analogous to 2) leaves The measuring device can even be installed to save space.

Literature:

• / 1 / First Regulation implementing the Federal Immission Control Act (Ordinance on Small Firing Installations -1. BlmSchV), Federal Law Gazette (1997), Part 1, no. 17, p. 491 et seq., Issued on 20.3.1997
• / 2 / LUTHER, Gerhard: "One Fatal error in the Kleinfeuerungsanlagenverordnung ", health engineer 117 (1996), pp. 113-126 accessible also over. http://www.uni-saarland.de/fak7/fze/KFA.htm
• / 3 / DIN 4702 - Part 8 "boiler - determination the standard efficiency and the standard emission factor "(March 1990), Beuth Verlag Berlin
• / 4 / RECKNAGEL-SPRENGER: Paperback for heating and air conditioning, Oldenbourg Verlag Munich, 68th edition 1997, page 670 ff (section 2.3.1-2.3.3c)
• / 5 / Wolff D., Teuber P., Budde J. and Jagnow K "Field investigation: Operating behavior of heating systems with gas condensing boilers. "Wolfenbüttel (April 2004) Final report of the project DBU - AZ 14133 of the German Federal Foundation Environment accessible also about: http://enev.tww.de/servlet/PB/menu/1022154/index.html
• / 6 / DIN 4705 - Part 1: "Firing technology Calculations of chimney dimensions ", available in the DIN Paperback, among others 146, Beuth-Verlag; Berlin; (1993)
• / 7 / D1N 4705, see / 6 /, page 17 - Table 1
• / 8 / VDI Heat Atlas Db7 / Verein Deutscher Ingenieure (VDI) (publisher): VDI Heat Atlas Calculation Sheets for heat transfer, 7th edition VDI-Verlag Dusseldorf (1994), Property of Water, Sheet Db7,
• / 9 / RECKNAGEL-SPRENGER see quote / 4 /, page 198: Table 1.3.6-6
• / 10 / DIN 4702 - Part 2 "boiler rules for the Thermal Testing "/ (March 1990), Beuth Verlag Berlin
• / 11 / Vogel.H.-N, "combustion technology Efficiency and exhaust gas loss of gas fired boilers ", BWK 48 (1996), Pages 72-78

1. Captions

Figure 1: "Rain barrel" as a buffer with level indicator: Over a wall passage 104 is the outside on the wall 100 the ton running level column 140 connected to the inside of the barrel, so that its level is on a scale 101 can be read. The water jack hose 142 is through a bracket 149 , which is carefully attached to the top of the barrel, thereby fixing and defining the evacuation threshold on the level line N4. If the water level exceeds the level N4, the water level switches 142 through and in the bin located condensate 1a flows through the drain line 144 from.

Fig. 2: Activated overflow device according to the water-jack principle: one on a spring 150 suspended activation vessel 155 runs over the activation water lift 152 (see picture 3) to 154 slowly full and shifts downwards as its weight increases, as soon as the water level behind the vessel wall 100 of the storage vessel 2a the level line N4 has reached. As a result, the holding device 156 , which is the vertex of the drain hose 142 determines well below the water level in the storage vessel 2a lowered and the storage vessel 2a Empties over the water jack 140 to 144 ,

Fig. 3: Activated overflow device: section perpendicular to the container wall 100 : Once the water level in the storage vessel 2a the level line N4 has reached the activation water heater switches 152 to 154 through and fill the activation vessel 155 , The feather 150 gives in to the increasing weight and to the activation vessel 155 firmly attached bracket 156 pushes the drain hose 142 significantly below the current levels in the storage vessel 2a , so in the drain hose 142 a safe pipe flow prevails. As the evacuation progresses, the activation vessel then becomes again 155 emptied and thereby raised.

Figure 4: Controlled emptying of a measuring volume with a single water leveler: exceeds the water level in the container 2 the level line N4 of the trigger threshold 42 , so there is an intermittent emptying of the accumulated condensate 1a that from the counter 10 via a float switch 8th (Details see Figure 5) is registered.

Picture 5: Lid 3 of the cache container 2 with displacement body 32 , Float switch 8th and condensate inlet 31 , The level line N4 identifies the threshold at which the trigger line 42 (see eg Figure 4) turns on.

Fig. 6: Reinforced drain with triggered double water lift: switching through the trigger threshold 42 the trigger line leads via the pressure compensation line 6 to a negative pressure in the main line 54 (Principle of the water jet pump) and thereby lifts that in the switching threshold 52 standing water over the level line N5; the main line goes through and massively increases the emptying of the storage tank 2 , The outlet connector 9 prevents air from entering the main line.

Picture 7: Simple outlet connector 9 , put together from a tee 92 and two elbows 91 and 93 , The outlet connector 9 ensures that the main line 54 by condensation water 1 is completed by the outside air. After dry fall, the outlet connector is first through from the trigger line 44 filled free flowing condensate water.

Figure 8: Triggered water lift with separate inlet for trigger and main line. The condensate water 1 flows through the drain line 4a into the trigger line 42 - 44 and over the separate intake trunk 5a into the main line 52 - 54 ,

Figure 9: The solenoid valve 77 , controlled by the float switch 85 , controls the drainage phases of the storage tank 2 , Each discharge is from the float switch 8th (see Figure 5) and detected by the meter 10 registered.

Figure 10: Controlled emptying of a measuring volume with a condensate pump: The condensate pump 75 emptied in one by the float switch 85 controlled intermittent operation between the switching points 86 and 87 lying measuring volume. Any such emptying of the storage container 25 is from the float switch 8th detected and from the counter 10 registered.

Picture 11: Water clock 7 measures the from the storage tank 25 intermittently pumped out condensate 1a , The condensate pump 75 emptied in one by the float switch 85 controlled intermittent operation the storage tank 25 , The drainage of condensate water 1a This is large enough for proper operation of the downstream water meter 7 to ensure.

Picture 12: Water clock 7 measures the condensate water formed by a simple water lift according to Fig. 4 into a pulsed pulsed discharge 1a ,

Picture 13: Water clock 7 Measures the condensate water formed by a triggered water lifter according to Fig. 6 to an increased burst-shaped drain 1a ,

Picture 14: Water clock 7 measures the through the solenoid valve 77 controlled amount of condensate 1a , The solenoid valve 77 , controlled by the float switch 85 , controls the drainage phases of the storage tank 2 , The water clock 7 always stays filled with water.

2. Designations in the pictures

N0

Niveaulinie des Luftzutritts im Auslauf-T-Stück 46 der Triggerleitung 40 – 44

N1

Niveaulinie des Luftzutritts im waagerechten Teil des T-Stückes 5

N2

Niveaulinie der Ansaugöffnung in der Ansaugleitung 4

N4

Niveaulinie des Wassers zur Auslösung der Trigger- bzw. Aktivierungsschwelle

N5

Niveaulinie des Wassers zum Durchschalten der Hauptleitung 50...54

N6

Niveaulinie der Druckausgleichleitung 6

N9

Niveaulinie der Wasseroberfläche im Auslauf-Verbinder 9

Level lines:

N0

Level line of air inlet in the spout tee 46 the trigger line 40 - 44

N1

Level line of the air inlet in the horizontal part of the tee 5

N2

Level line of the suction opening in the suction line 4

N4

Level line of the water to trigger the trigger or activation threshold

N5

Level line of the water for switching on the main line 50 ... 54

N6

Level line of the pressure compensation line 6

N9

Level line of the water surface in the outlet connector 9

3. pictures 1-14 without captions

• Picture 1: "Rain barrel" as a cache with level indicator
• Figure 2: Activated overflow device after the water-jack principle
• Picture 3: Activated overflow device: Section perpendicular to the container wall
• Figure 4: Controlled emptying of a measuring volume with simple Water lift
• Picture 5: Lid 3 of the cache container 2
• Picture 6: Reinforced Drainage with triggered double water siphon
• Picture 7: Simple outlet connector 9
• Figure 8: Triggered water lift with separate inlet for trigger and main.
• Figure 9: Solenoid valve 77 , controlled by the float switch 85 , controls the drainage phases of the storage tank 2 ,
• Figure 10: Controlled emptying of a measuring volume with a Condensate pump.
• Picture 11: Water clock 7 measures the from the storage tank 25 intermittently pumped out condensate 1a ,
• Fig. 12: Water meter measures condensate water formed by a simple water lift according to Fig. 4 into a pulsed pulsed discharge 1a ,
• Fig. 13: Water meter measures condensate water formed by a triggered double water lift in order to increase the impact-like flow 1a ,
• Fig. 14: Water meter measures that controlled by the solenoid valve Amount of condensate.

Claims (13)

Method for the direct determination of the net exhaust gas loss of a firing plant, in which at least in normal operation partial condensation of the water produced during combustion occurs in the boiler or in the exhaust system, characterized in that the amount of the total accumulating condensate is measured and from this the net exhaust gas loss is determined , Method for the separate determination of gross exhaust gas loss and fireplace heat in a firing plant where it is in the boiler and / or in the exhaust system at least in normal operation for partial condensation of the at Incineration of water, characterized, that the condensate from the exhaust pipe before it enter the boiler can be decoupled by a branch from the exhaust pipe, and then the condensate levels in the boiler and in the exhaust system be measured separately and determined from this gross exhaust gas loss and fireplace heat become. Method according to claim 1 or 2 for the electronic Determination of the exhaust gas loss of a combustion plant, characterized on the one hand, an electrical count signal for the condensate and on the other hand, an electrical counter signal the responsible gas meter, or one derived from the burner unit of the boiler Signal from which the current burner output can be determined, or an electrical measuring signal between a forward and a return of the heat generator installed heat meter electronically be registered and evaluated, and from linking this Information by electronic means Key figures for the exhaust gas losses calculated and displayed. Apparatus for measuring the condensate accumulation of a furnace in carrying out the method according to claim 1 or 2, characterized in that - the water flow to be measured in a temporary storage storage vessel (( 2 ) respectively. ( 2a ) respectively. ( 25 )) is collected and that - an emptying of this storage vessel is triggered upon reaching a predetermined upper level and that - such emptying is stopped at a fixed predetermined lower level, which here can also be a complete drain, and that - the number of such evacuations by a counter ( 10 ) is registered. Device for triggering the emptying of the storage vessel ( 2 ) A device according to claim 4, characterized in that the condensate water in the drain from the storage vessel in a arranged according to the principle of the water lift line ( 40 ) - ( 44 ) to be led. Device for increasing the outflow stream during emptying of the storage vessel ( 2 ) a device according to claim 4, characterized in that a first water level ( 40 ) - ( 44 ) via a pressure compensation line ( 6 ) one in its switching threshold ( 52 ) just above the trigger threshold ( 42 ) of the first water lifter arranged second water lifter ( 50 ) - ( 54 ) first according to the principle of the water jet pump in the region between its water level and the air inlet from the outside preventing spout connector ( 9 ), in which open the drain water of both the first water jack and the second water jack, vented slightly, thereby causing a popping of the second water jack. Device for triggering the emptying of the storage vessel ( 2a ) a device according to claim 4, characterized in that a water hose (( 152 ) and ( 154 )) at the nominal filling level N4 through the wall ( 100 ) of the storage container ( 2a ) and a first part ( 152 ) in its interior and with a second part ( 154 ) is in the outer space and that after reaching the desired level level N4 within the memory ( 2a ) Water through this water hose according to the principle of the water lifter in an activation vessel ( 155 ) which passes over a mechanical spring ( 150 ) at one with the storage vessel ( 2a ) rigidly connected spring-holding device ( 151 ) and that on this activation vessel ( 155 ) a holding device ( 156 ), which serves as the vertex for a drain hose ( 142 ), which works according to the principle of the water lift with the lower part of the storage vessel ( 2a ), wherein: - the activation vessel ( 155 ) when water enters the storage vessel ( 2a ) by its increasing weight the spring ( 150 ) pulls you apart, yourself. lowers and thereby serving as the vertex of the drain hose holding device ( 156 ) below the level of the water in the storage vessel ( 2a ) and thereby the emptying of the storage vessel ( 2a ) via the drain hose ( 142 ), and - in the activation vessel ( 155 ) through the connecting tube (( 152 ) and ( 154 )) with the storage vessel ( 2a ) a level compensation (according to the principle of communicating tubes in conjunction with the principle of the water lift) takes place, - and the further drop in the level in the storage vessel ( 2a ) finally water from the activation vessel ( 155 ) back into the storage vessel ( 2a ) runs back, while the activation vessel ( 155 ) by its weight decreasing by this outflow through the spring ( 150 ) is pulled upwards, and thereby serving as the vertex of the discharge hose holding device ( 156 ) is finally pulled over the level setpoint height N4 and thereby remains in the inactive state above the level setpoint height N4. Apparatus according to claim 4, characterized in that the emptying of the measuring volume in the storage vessel ( 2 ) via a solenoid valve ( 77 ) is controlled in the sequence, wherein the solenoid valve by a float switch ( 85 ) is driven. Apparatus according to claim 4, characterized in that the emptying of the measuring volume in the storage vessel ( 25 ) on the switching on and off of a condensate pump 75 is controlled. Apparatus for measuring the condensate accumulation of a combustion plant in carrying out the method according to claim 1 or 2, characterized in that - the condensate water 1 first in a temporary storage vessel (( 2 ) respectively. ( 25 )) and that - a short-term emptying of this storage vessel, which need not necessarily be complete, is triggered upon reaching a predetermined upper level and that - the amount of condensate flowing during such emptying ( 1a ) by a water meter ( 7 ) is measured. Apparatus according to claim 10, characterized in that the drain of the condensate water from the storage vessel ( 2 ) by a solenoid valve ( 77 ) in a device according to claim 8 or by a triggered according to the principle of the water lifter or activated device according to one of claims 5 to 7 or by the switching on and off of a condensate pump ( 75 ) is controlled. Device according to one of claims 4 to 9, characterized that the volume of the effluent during each discharge process water a round value (e.g., 1000 ml, 500 ml, 2000 ml, etc.) containing the Conversion of the counter result facilitated in a volume corresponds. Device according to one of claims 4 to 9, characterized in that to facilitate the interpretation of the counter result, the volume of water flowing out during each counting process directly or in the resulting during the combustion of 1 m ³ natural gas combustion water (eg 1.6 l for natural gas H) corresponds to an integer ratio.