GB2568947A

GB2568947A - A combi-boiler device

Info

Publication number: GB2568947A
Application number: GB1720086.6A
Authority: GB
Inventors: Sheppard Luke Michael
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-12-01
Filing date: 2017-12-01
Publication date: 2019-06-05
Anticipated expiration: 2037-12-01
Also published as: GB201720086D0; GB2568947B; GB2568947A8

Abstract

A combi-boiler device 99 has first and second heat exchangers 16, 19, an internal boiler channel 57, 58, 59 from the first to the second exchanger, a heating channel 1, 4 (e.g. for a central heating system), a hot water channel 2, 3 (e.g for a domestic hot water supply), and a diverter 10. The diverter is arranged to divert heated water from the first heat exchanger to the heating channel or the second heat exchanger, and to allow a partial heating channel flow until the second exchanger has reached a predefined temperature. Hence, instead of cutting off hot water supply to the heating channel when a tap is turned on, both the heating and hot water channels may be supplied simultaneously. The diverter may comprise a dual zone valve fitted with independent actuators. Temperature sensors 6, 7, 8, 9, 18 may be arranged on the heating channel, on an egress and ingress of the second heat exchanger, and on the hot water flow and return pipes.

Description

The present invention relates to a combi-boiler device, in particular a device for providing a more efficient combi-boiler; more particularly a device that is a combi-boiler or a device for modifying a combi-boiler.

Background

Increasing proliferation of on-demand gas boilers that also double up as hot-water heaters is a factor in many societies. These typically have two independent heat exchangers where a first heat exchange carries a pipe through to the radiators, and a second heat exchanger carries a similar pipe through to the hot water supply. When a user turns on a hot water faucet or tap, a flow switch in the boiler detects there is a hot water outlet open, and operates a motorised three-port valve, redirecting the boiler flow from heating radiators to the secondary heat exchanger. At the same time, the flow switch operates a relay switch which in turn switches on the boiler and primary pump, providing heat. The heat exchanger transfers heat from the hot water in the boiler circuit flow to mains domestic water, thereby providing hot water to the taps.

If it's a central heating boiler, it usually has to pause from heating the central heating water while it's heating the hot water, because it can't supply enough heat to do both jobs at the same time so that demand from the central heating is bypassed allowing the full boiler output to be utilised for hot water. When all hot outlets are closed, the three-port valve redirects the boiler flow back to its usual route.

Therefore when a current generation combination boiler is in the process of supplying heating switches on the hot water tap, a delay is incurred as valves result in a boiler having to stop and power down to switch over to supplying hot water. This results in energy losses and an intermittent supply of hot water as well as shutting off complete flow to the central heating system. Further to this, when the tap is turned off after use the boiler turns off and activates the bypass valve and internally cools down the primary flow. The diverter valve then re-opens 30 seconds later and begins flow to the central heating. This results in further energy losses and delays.

Prior Art

KR 101 581 129 (SHIMADA et al) discloses a heating system for supplying hot water which prevents a temperature of hot water supplied from a hot tap from getting lower than a target hot water temperature when a hot water supply operation and a heating operation are performed at the same time. The heating system for supplying hot water comprises: a heating flow rate adjustment valve to adjust a flow rate of hot water flowing in a heating pipe; and a priority control unit to perform hot water supply priority control to reduce a flow rate of the hot water flowing in the heating pipe by the heating flow rate adjustment valve when a heating operation and a hot water supply operation are performed at the same time, and the sum of heat consumed for the heating operation and heat consumed for the hot water supply operation is higher than or equal to the maximum heat which can be supplied by a heat source.

EP 1 582 824 (GALLUS) discloses a boiler unit including a first circuit for heating of heat-transferring fluid to be sent to a heating system for house rooms and a second circuit for heating of sanitary water to be sent to sanitary water users with said first circuit including a primary heat exchanger for heating the heat-transferring fluid and said second circuit including a secondary heat exchanger for heating sanitary water with said boiler unit including detection means of the required heated sanitary water flow and means of diverting from said first circuit a fraction of the flow of the heattransferring fluid to send it to the secondary heat exchanger with said diversion means being controlled by control means connected to the detection means to regulate the size of said fraction as a function of the detected sanitary water flow requirement.

EP 0 981 031 (CHOI) discloses a heating water flow circulation and hot sanitary water supply apparatus in a combi-boiler which preheats cold water during heating and instantaneously supplies hot water when turning a tap on for use in the kitchen and bath room, etc. The apparatus comprises a water-to-water heat exchanger, in which sanitary water layers and heating flow layers are alternately multilayer-formed to perform heat exchange between heating flow and sanitary water, and a heating flow diverting unit controls the direction of the heating flow circulation according to a heating mode or a hot sanitary water supply mode. The apparatus supplies the hot sanitary water by circulating part of the heating flow to the heating flow layers of the water-towater heat exchanger while the supplied heating flow is circulated for heating.

The present invention arose in order to overcome problems suffered by existing devices.

Summary of the Invention

According to the present invention there is provided a combi-boiler device having a first heat exchanger and a second heat exchanger, an internal boiler channel from the first heat exchanger to the second heat exchanger, a heating channel and a hot water channel, and a diverter arranged to divert heated water from the first heat exchanger to the heating channel or to the second heat exchanger; characterised in that the diverter is arranged to allow a partially diverted heating channel until the second heat exchanger has reached a predefined temperature.

In some embodiments the device is arranged to restrict flow to the heating channel while opening a hot water valve inside the diverter so as to maintain temperature in the primary channel flow/return until the second heat exchanger is at a sufficiently high temperature.

The device of the present invention enables the main heat exchanger to heat both the heating channel and the hot water channel simultaneously. As a consequence, the typical diversion of heat via the bypass in a combi boiler from heating channel to hot water channel when a tap is opened may be avoided, and efficiency maximised.

This may be of particular consequence in boilers which are arranged to turn off on recognition of an open hot water tap, so as to divert the primary channel to the second heat exchanger via the hot water channel and temporarily turn on to heat the second heat exchanger and hot water.

The diverter may comprise dynamic operability. For example the diverter may comprise a thermostat, which thermostat is arranged to control a valve or valves. In this way the diverter may be arranged to divert water according to recognition of temperatures, for example temperature of the output to the hot water channel. In some embodiments one or more thermostats or thermal sensors may be incorporated into the diverter.

In other embodiments one or more thermostats or thermal sensors may be arranged on channel piping to or from the diverter. In such manner the temperature of the second heat exchanger (flow/return), hot water flow, heating flow/return and primary flow and return from the first heat exchanger may be monitored.

In some embodiments the diverter comprises temperature sensors. In some embodiments the diverter includes a printed circuit board or microprocessor arranged to monitor multiple temperature sensors and operate valves to divert water according to predefined algorithms.

In some embodiments the diverter may be defined to comprise multiple parts, for example including discrete parts, and/or a kit of parts, for example for use in aftermarket situations, and/or locations about a boiler. In some embodiments the diverter may comprise a dual zone valve both fitted with independent actuators. In some embodiments the diverter may comprise a three-way electrically operable gate valve operable to divert between channels.

In some embodiments the diverter may comprise wireless operability or connectivity. For example in some embodiments comprising a multipartite diverter, the various parts may be arranged to wirelessly communicate. In such embodiments the temperature sensors may feed temperature data to a main diverter unit, which unit is controlling flow to these temperature sensors. Alternatively or additionally wireless connectivity may enable the diverter to be remotely operated or adjusted.

In some embodiments the diverter may comprise a system of burner modulation. For example, once the second heat exchanger has reached a desired temperature, as the heating flow opens to allow flow to radiators the burner may modulate or regulate so as to suit temperatures at ingress of the heating flow to the boiler.

This will allow the boiler to adjust and keep at a stable temperature always.

The diverter in some embodiments may therefore be defined to comprise burner regulation or control apparatus.

In some embodiments the device comprises a manufactured combination boiler incorporating the diverter. In other embodiments the diverter may be available independently, and the present invention comprises a method of fitting a diverter to an existing boiler.

In this way the device of the present invention works by keeping the boiler continually running, simultaneously able to supply hot water and central heating.

It does this by regulating the temperature of the secondary heat exchanger that indirectly heats the hot water channel to supply the running hot water to taps or faucets.

When the user turns on the hot tap the device dynamically reduces flow to the heating until the secondary heat exchanger has reached an effective temperature and can handle exchanging more heat than is required for the tap hot water channel.

In some embodiments the device of the present invention may be arranged to constantly monitor temperature fluctuations in the second heat exchanger ensuring no unwanted temperature drops. For example the primary channel may be arranged to partially and/or periodically include the second heat exchanger even when the flow is primarily directed to the heating channel.

The device may also incorporate or communicate with the burner, modulating the gas required to keep all channels at a consistent temperature.

In this way the device increases the amount of flow to the radiators after the second heat exchanger has reached a temperature appropriate to the hot water requirements of the user, thereby intelligently maintaining a consistent temperature within the boiler’s internal flow system. This limits the typical transfer of heat from the first to second heat exchanger and attendant drops in temperature within the boiler internal flow system.

A preferred embodiment of the invention will now be described by way of example only and with reference to the Figures in which:

Brief Description of Figures

Figure 1 shows a diagrammatic view of an embodiment of the device comprising a combi-boiler;

Figure 2 shows a diagrammatic view of an embodiment of a diverter for use in a device according to the present invention;

Figure 3 shows a schematic view of temperature patterns in a combi-boiler known in the art;

Figure 4 shows a schematic view of temperature patterns in a combi-boiler embodiment of the device according to the present invention; and

Figure 5 shows a schematic view of a flow pattern in a combi-boiler device according to the present invention.

Detailed Description of Figures

With reference to the figures there is shown generally embodiments of a combi-boiler device 99 having a first or main heat exchanger 16 and a second or secondary heat exchanger 19, an internal or primary channel 59 from the main heat exchanger 16 to the secondary heat exchanger 19, a heating channel flow 1, heating channel return 4, a hot water channel comprising a cold water inlet 3 and a hot water out 2 and a diverter 10 arranged to divert heated water from the main heat exchanger 16 to the heating channel 1, or to the secondary heat exchanger 19 via the primary channel 57; characterised in that the diverter 10 is arranged to allow a partial heating channel until the secondary heat exchanger 19 has reached a predefined temperature. The return/flow may be reversed in further embodiments.

In particular reference to Figure 1 the embodiment shown comprises a boiler arranged to incorporate the device, wherein the diverter comprises a unit 10 which is arranged on the boiler primary channel return 59 and temperature sensors 7, 8, 9 18, 6, and wherein the embodiment shown further comprises the following:

Flue 14

Pump 12

Bypass valve 11

Heating channel egress piping 1

Heating channel return or ingress piping 4

Cold water piping 3 for the hot water channel

Hot water piping 2 for the hot water channel

Diverter unit 10

Main heat exchanger 16

Secondary heat exchanger 19

The temperature sensors 7, 8, 9 18, 6 are arranged to monitor local temperatures and wirelessly (or wired if preferred) provide information to the diverter unit 10, which internally includes a microprocessor and a bifurcated valve arrangement, enabled to divert flow between the heating channel and the secondary heat exchanger via the hot water flow, wherein the secondary heat exchanger heats the cold water received through piping 3 to create the hot water flow 2.

The valve arrangement comprises of two mechanically driven pivoting ball joints fitted with independent actuators splitting flow progressively between either the outgoing heating channel flow 1 or the second heat exchanger through internal channel piping 57.

This allows dynamic control of channels and flows in respect of the secondary heat exchanger wherein as the secondary heat exchanger rises in temperature through passage of heated water from the boiler primary channel flow the proportion of water diverted from the heating channel flow is reduced and allowed to continue the radiator usage.

In the embodiment pictured in Figure 1 the temperature sensors are located at the ingress 6 and egress 7 of the heating channel flow, egress of heating channel return 4, hot water channel 8 and 9 and (18) between the diverter unit 10 and the second heat exchanger 19. The return/flow may be reversed in further embodiments.

In this way flow through the second heat exchanger 19 from the internal channel 57, 58, 59 may be modulated by monitoring of the differential between the ingress and egress of the primary channel 57, with reference to the temperature of the hot water channel outlet 2 and diversion from the heating channel 1, 4 dynamically controlled.

The diverter unit 10 is located on the egress of the primary channel return after the secondary heat exchanger in the pictured embodiment but in other embodiments may alternatively be located on the primary flow channel to the secondary heat exchanger.

In the embodiment pictured in Figure 1 a spur 17 for internal cycling, is typical to combi boilers for bypassing purposes.

The invention has been described by way of examples only and it will be appreciated that variation may be made to the above-mentioned embodiments without departing 15 from the scope of invention as defined by the claims, in particular but not solely combination of features of described embodiments.

Claims

1. A combi-boiler device having a first heat exchanger and a second heat exchanger, an internal boiler channel from the first heat exchanger to the second heat exchanger, a heating channel and a hot water channel, and a diverter arranged to divert heated water from the first heat exchanger to the heating channel or to the second heat exchanger; characterised in that the diverter is arranged to allow a partially diverted heating channel until the second heat exchanger has reached a predefined temperature.

2. A combi-boiler device according to claim 1 wherein the diverter comprises a diverter unit dual zone valve both fitted with independent actuators and a plurality of temperature sensors.

3. A combi-boiler device according to claim 2 wherein the diverter unit comprises a dual zone valve both fitted with independent actuators.

4. A combi-boiler device according to claim 2 or 3 wherein the temperature sensors are arranged on the heating channel, the primary channel, and the hot water egress.

5. A combi-boiler device according to any of claims 2 to 4 wherein the temperature sensors are arranged on the egress and ingress of the second heat exchanger.

6. A combi-boiler device according to any of claims 2 to 5 wherein the temperature sensors are arranged on the hot water channel flow/return pipework.

7. A central heating system including the combi-boiler of claim 6, pipes, valves and radiators.

7. A combi-boiler includes the device according to any of claims 1 to 6.

8. A central heating system includes the combi-boiler of claim 7, pipes, valves and radiators.

Amendments to the claims have been filed as follows

Claims

1. A combi-boiler device having: a first heat exchanger and a second heat exchanger; an internal boiler channel from the first heat exchanger to the second heat exchanger; a heating channel; a hot water channel; a plurality of temperature sensors and a diverter including a dual zone valve with independent actuators arranged to selectively divert heated water from the first heat exchanger to the heating channel and/or to the second heat exchanger upon user demand of heated water.

2. A combi-boiler device according to claim 1 wherein the diverter is arranged to allow a partially diverted heating channel until the second heat exchanger has reached a predefined temperature.

1206 18

3. A combi-boiler device according to any preceding claim wherein temperature sensors are arranged on the heating channel, the internal boiler channel, and the hot water egress.

4. A combi-boiler device according to any preceding claim wherein temperature sensors are arranged on the egress and ingress of the second heat exchanger.

5. A combi-boiler device according to any preceding claim including at least one temperature sensor is on the hot water channel.

6. A combi-boiler including the device according to any of claims 1 to 5.