DE29914331U1 - Arrangement for heating warming devices and the like. in hotels, laboratories and the like - Google Patents

Description

Arrangement for heating warming facilities and the like in hotels, laboratories and the like

The invention relates to an arrangement for heating warming devices in hotels, food stalls and the like as well as in laboratories and similar facilities where food, reagents and the like are to be temporarily stored at medium heat and constant temperature.

According to the usual arrangements, food counters, warming cabinets and laboratory cupboards and similar facilities in which food, reagents and similar sensitive substances must be temporarily kept at a constant warming temperature are kept at medium temperatures using conventional heating media. These are regularly temperatures that reach up to 70 ° Celsius. In view of the necessary regulation and autonomous operation of such facilities, electrical energy is usually used.

The object of the invention is therefore to propose an arrangement, in particular for keeping food warm in dining counters in hotels and similar establishments and for tempering reagents in laboratories and similar warming facilities, in which the use of conventional energies can be reduced as far as possible and the use of alternative energies can be given priority in the new manufacture or reconstruction of such facilities within the scope of the available resources.

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The task is solved by connecting the output of a thermal solar system, which is dimensioned according to the expected energy requirement, to the input of a heat exchanger arranged in a storage tank. The heat contained in the heat transfer medium I supplied by the thermal solar system is transferred to another heat transfer medium II via this heat exchanger. In the event that solar energy is not available in the required amount due to weather conditions, a conventional heating element is present in the storage tank.

In order to ensure the return of the heat transfer medium I, the heat exchanger is coupled to the thermal solar system in such a way that a circuit is created.

To speed up the heat exchange, a first circulation pump is preferably installed in the return line to the solar thermal system, the speed of which is controlled by the temperature difference that occurs between the measuring points at the output of the solar thermal system and the average storage temperature in the tank. If the temperature difference is large, the speed of the circulation pump is increased; if the temperature difference is small, the speed of the circulation pump is reduced.

The storage tank and the heating device to be operated are again connected to one another by a pipe through which a heat transfer medium II is fed from the usually warmest point of the storage tank via a second circulation pump. In the immediate vicinity of the substances to be kept at a certain temperature, such as food or the like, there is another heat exchanger II through which the heat is transferred to the substances to be kept at a certain temperature. The return of the heat exchanger II is in turn connected to the point in the storage tank where the lowest temperature is expected.

According to a practical embodiment of the invention, the second circulation pump is electrically/electronically coupled to a timer in order to be able to operate the arrangement in a predetermined and time-fixed manner.

To vary the temperature of the materials to be kept warm, a short-circuit section is arranged in front of the heat exchanger II, connecting the flow and return lines. In the flow of the heat transfer medium II, between the branch of the short-circuit section and the inlet of the heat exchanger II, a thermostat valve is arranged in the flow line leading to the heat exchanger II. This is used to change the cross-section in the flow line to the heat exchanger II. This allows the temperature in the heating circuit in the immediate vicinity of the materials to be kept warm to be regulated.

The supply and return lines are laid in the immediate vicinity of the materials to be kept at temperature, i.e. where the heat is ultimately provided, in such a way that there is a return line next to each supply line, so that the temperature and heat transfer are as uniform as possible and differences due to a serious temperature gradient between adjacent lines are not present.

In the case of multi-level warming systems with different heat requirements of individual shelves, several control circuits are provided to correspond to the differences, which are arranged in parallel according to the invention.

The combination of components known in detail according to the invention using solar energy as the main heat carrier results in considerable energy savings when operating heating devices, which

This is particularly significant in the summer months. In a calendar year, this figure is 60...70%.

The invention will be explained in more detail below using an embodiment.

In the accompanying drawing

Fig. 1 the arrangement of individual components for the inventive

Design of a food serving counter in a company canteen.

Fig. 2 the arrangement of a heating circuit in a warm hall

tebecken in plan view, with the supply line blackened and the return line contoured.

A thermal solar system consists of standard collector elements 1, the solar station 2 with control and the storage tank 3. The storage tank 3 has a temperature monitor, which switches on a gas-powered additional heating 4 when the temperature in the storage tank 3 falls below a minimum. When the set upper temperature is reached, the temperature monitor switches the gas-powered additional heating 4 off again. From the upper area of the storage tank 3, a flow line 5 leads via a circulation pump 6, which is coupled to a timer on which the desired operating time can be set, to a warming basin 7 of a food counter 8. Before reaching the food counter 8, the flow line 5' or 5" leading to the food counter 8 is connected to the return line 9 leaving the food counter 8 and returning to the storage tank 3 via a line 10 that short-circuits both lines. Between the branch of the short-circuit line 10 and the food counter 8

A thermostat valve 11 is arranged in the flow line 5". This thermostat valve 11 closes or opens the flow line 5", so that the temperature of the heat transfer medium in the entrance of the food counter 8 can be adjusted and ultimately maintained by the thermostat effect.

In the schematic diagrams, forward and return flow are marked by corresponding arrows.

In the area directly relevant for keeping food warm, the pipes carrying the heat transfer medium are laid in such an intertwined manner that the supply pipe 5" is located directly next to the return pipe 9. This is the same laying technique as is used when laying pipes for underfloor heating.

The pipes laid outside a warming basin arranged in a food counter 8 are preferably made of copper. If the temperature-carrying pipe in such a warming basin is in contact with water, plastic pipes with the designation PE-X are laid, which have good thermal conductivity when in contact with water without complications.

The insulation has not been shown because, although it is essential for the functioning of the system, it is not essential to the invention. Control-related dependencies between the components of the solar system were also not mentioned.

Claims (6)

1. Arrangement for heating warming devices such as warming shelves, warming cabinets and the like in hotels, laboratories and the like, in which a thermal solar system is arranged to feed the heat transfer fluid to a downstream storage tank ( 3 ) with an integrated heat exchanger, characterized in that the heat exchanger integrated in the downstream storage tank ( 3 ) is connected to the heating pipes of a warming device via a conventional ring line, a short-circuit section ( 10 ) is arranged immediately in front of the warming device between the flow line ( 5 ) and the return line ( 9 ) of the ring line and an adjustable thermostat valve ( 11 ) regulating the inflow is present between the branch of the short-circuit section ( 10 ) and the warming device. 2. Arrangement according to claim 1, characterized in that in the warming device the supply and return lines ( 5 ; 9 ) are arranged directly next to one another. 3. Arrangement according to one of claims 1 or 2, characterized in that, in the case of different supply points within a heat-retaining device, the ring line is adequately split into parallel sub-circuits. 4. Arrangement according to claim 3, characterized in that a controllable thermostat valve ( 11 ) is arranged in each sub-circuit with the same or different heat requirement. 5. Arrangement according to one of claims 1 to 4, characterized in that a circulation pump ( 6 ) is arranged in the ring line between the integrated heat exchanger and the warming device. 6. Arrangement according to claim 5, wherein the circulation pump ( 6 ) is electrically-electronically coupled to a programmable timer for controlling its operating state.