DE2637209A1 - Heat pump supplying hot water and partial space heating - has supplementary space heater switched to give hot water, when needed - Google Patents

Abstract

The heat pump supplies, in the first place, hot water. When the hot water target temp. is reached, the surplus heat is diverted to room heating. An auxiliary heater supplies any remaining heating requirement. A preferably manual switch is provided so that the auxiliary heater can also be used to increase the hot water supply, when necessary.

Description

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is when the heat pump in the event of a malfunction, z. B- failure of an auxiliary unit the heat pump, does not convey any heat into the heating network.

State of the art

The invention is based on a heating system according to the preamble of the main claim. Such a heating system is already known (DT-OS 24 51 544.4-16), in which the auxiliary heating can only be switched on when an increased heat output of the room heating via a flow temperature controller body is challenged. In this system, the additional heating is not full exploited because it is only used on a relatively few days a year.

Advantages of the invention

The arrangement according to the invention with the characterizing features of the main claim On the other hand, it has the advantage that the additional heating is also used when a large amount of domestic water is consumed in the shortest possible time should be tapped, e.g. to fill a bathtub. Be that way the system costs of the additional heating are used more economically than before. The additional heating can be designed so that in the event of a fault the heat pump and stand-alone operation of the additional heating a lower heating temperature adjusts so that the user of the system remains aware of the disturbance.

The measures listed in the subclaims are advantageous Further training and improvements to the heating system specified in the main claim possible. It is particularly advantageous if the domestic water thermostat acts on a changeover contact, on whose fixed mating contacts two control lines for the additional heating are connected, the first of which is a switching contact of the thermostat controlling the heat transport to the space radiators or controller and the other one by an arbitrarily operable Contains operating member influenced switch contact.

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drawing

An embodiment of the invention is shown in the drawing and explained in more detail in the following description. FIG. 1 shows the inventive Heating system in a schematic representation and Figure 2, the electrical switching means of the system, as far as it is necessary to understand the invention are necessary.

Description of the invention

The heating system has a heat pump 10, which essentially consists of an evaporator 11, a condenser 12, a compressor 13 and an expansion valve 14. The evaporator 11 is supplied by a pump 15 from a well or river water supplied. Instead of water, the evaporator can of course can also be operated with air from the environment. The heat pump has a line network 16 in which a refrigerant is in a closed circuit is transported by the compressor 13. This evaporates in the evaporator 11 liquid refrigerant and takes from the pump 15 pumped water Warm up. From the evaporator, the refrigerant reaches the compressor 13, where it is compressed and transported to the condenser 12, where it is liquefied and it gives off heat to a heating network 17.

The expansion valve 14 is located between the condenser 12 and the Evaporator 11. A solenoid valve 18 is arranged between expansion valve 14 and condenser 12. Between the evaporator 11 and the compressor 13 there is a pressure switch 19 and a safety switch 20. A second safety switch 21 is between the compressor 13 and the Condenser 12 arranged. The low-pressure region of the refrigerant circuit that extends between the expansion valve 14 and the compressor 13 is with 22, and between the compressor 13 and the expansion valve 14 extending high pressure area designated by 23.

The heating network 17 has a pre-running line. 26, 27, 28 ,. those about electromagnetic Switching valves 29 and 30 leads to radiators 31, which in the to heating rooms are installed. From the radiators 31 leads a return

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Running line 32 via a circulation pump 33 to the condenser 12 of the heat pump return. The switching valve 29 has a magnet 36 and monitors a branch line 37, which leads through the heat exchanger 38 of a gas-heated instantaneous water heater 39, which works as an auxiliary heater. The branch line 37 opens at the collecting point 40 into the flow line section 26. The switching valve 3O has a magnet 42 and controls a branch line 43 that leads to a Domestic water storage tank 44 leads, in the interior of which the branch line 43 forms a heating coil 45. The domestic water occurs at a nozzle 46 in the Memory 44 in and out of the memory at a nozzle 47. The branch line 43 opens at a collecting point 48 into the return line 32 of the heating network.

The compressor 13 has a pole-changing drive motor that has a Switching device 50 is connected to the network. The switching device 50 is part of a control device, its switching elements, insofar as they are used in the present context interest, are shown in Figure 2. A line 51 branches off from the line S and leads via a switch 52 to a branch point

53 leads. The switch 52 is a monitoring switch of an auxiliary device the heat pump, which interrupts the line 51 if the auxiliary device is not working properly. At branch point 53 there is a line

54 and a changeover contact 55 actuated by the pressure switch 19 connected, which cooperates with two fixed mating contacts 56 and 57. The arrangement is such that the changeover contact 55 is in the position shown assumes, as soon as and as long as the pressure of the refrigerant in the low-pressure region 22, the atmospheric pressure by a certain value, z. B. by 1.5 bar does not exceed. When this value is exceeded, the changeover contact 55 is switched over to the fixed mating contact 57.

The line 54 leads to the switch to be described in more detail below Solenoid valve 18 in the refrigerant circuit. To the mating contact 56 of the changeover contact 55, a control relay 6O is connected via a line 58, which Forcing the refrigerant to be sucked out of the low-pressure area 22 when the compressor 13 is restored after a temporary power failure starts up. A line 61 is connected to the mating contact 57 of the changeover contact 55, via the switch to the Switching device 50 leads.

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The line 54 leads to a branch point 62, from which two lines lead to a collection point 63, one of which from a contact 64a one Domestic hot water thermostats 64 and the other from a contact 65a of a room temperature controller 65 and monitored by a so-called Sommer / Wintor switch 66 is. The switch 66 is open in summer mode, so that the heat pump can only be switched on when there is a demand for heat from the domestic water thermostat 64. The solenoid valve 18 is at the collecting point 63 via a normally open contact 6Oa des Relay 6O connected. This has a second make contact 60b, which as Self-holding contact for the relay acting the changeover contact 55 bridged.

A second contact 64b of the service water thermostat 64 is connected to the line 61 connected, which is a control line when heat is requested by the thermostat 64 67 closes for a first switched-on position of the switching device 5O, in which the drive motor of the compressor 13 runs at a higher speed. The switching device 5O has a second control line 68 from a changeover contact 65b of the room temperature controller 65 and a contact 64c of the domestic water thermostat 64 is monitored. The changeover contact 65b closes the control line 68 when the room temperature controller 65 has no or only a moderate amount of heat requests. When a high amount of heat is requested by the room temperature controller 65, the changeover contact 65b goes into the second switching position, in which it closes the S expensive line 67. The switching contact 64c is with the SchaltkontaJct 64b mechanically connected in such a way that one contact is open when the other is in the closed position, and vice versa. When the control line is closed 68 the drive motor of the compressor 13 runs at a lower speed.

The circulating pump 33 can be connected to the network via a relay 7O, its excitation circuit is controlled by a changeover contact 66a of the summer / winter switch 66 and a switch contact 64d of the domestic water thermostat 64. Take the parts the position shown in the drawing when the switch 66 is set to winter operation and the domestic hot water thermostat 64 is not requesting any heat. The domestic hot water thermostat 64 has a further switching contact 64e, which the magnet 42 of the switching valve 3O controls. When there is a demand for heat from the domestic hot water thermostat 64, the magnet 42 is excited and thereby the switching valve 3O is set so that the connection between the flow line sections 27 and 28 is interrupted and a connection between the line section 27 and the branch line 43 is established

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is. When the magnet 42 is not excited, the line sections 27 and 28 connected to each other, while the branch line 43 of the flow line is separated.

The heating system 39 is via a solenoid valve 80 in the fuel supply channel 81 controlled. The solenoid valve 80 can be connected to the network via two lines 82 and 83, which are connected to the service water via a changeover contact 64f. thermostats 64 are controlled. The changeover contact 64f assumes the position shown when there is a demand for heat from the domestic water thermostat 64 does not exist. In line 82 there is also a switch contact 65c of the room temperature controller 65, a switch contact 66b of the summer / winter switch and a switching contact 60c of the relay 6O is arranged. The switch contact 60c is bridged by a branch line 85 which is monitored by the normally open contact 86a of a manually operated switch 86. The desk 86 has a second working contact 86b which is permanently coupled to the working contact 86a and which monitors the line 83. The arbitrarily operable Switch 86 is used in the manner described in more detail below to quickly heat larger quantities of domestic water in addition to the heat pump also switch on the auxiliary heating.

The system described works as follows:

The parts assume the position shown in the drawing, if neither The domestic hot water thermostat 64 still requests heat from the room temperature controller 65, and if the pressure of the refrigerant is in the low pressure range 22 does not exceed the pressure of 1.5 bar above atmospheric pressure. In this case, the solenoid valve 18 and the refrigerant circuit are de-energized closed. The relay 60 is excited via the changeover contact 55 and the self-holding contact 60b. The compressor 13 is switched off because the switching device 50 receives power neither via the control line 67 nor via the control line 68. The circulation pump 33 is switched on via the relay 70, while the solenoid valve 8O of the heating system 39 is de-energized and the fuel supply to its burner is interrupted. Furthermore, the Solenoids 42 and 36 are de-energized, so that the two switching valves 29 and 30 assume their basic position in which they the branch lines 37 and 43 lock.

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In the event of an average heat demand by the room temperature controller 65, the switching contact 65a is closed, while the switching contacts 65b and 65c maintain their position shown. These contacts are only moved into their other switching position when the room temperature controller 65 requests an increased amount of heat per unit of time in the event of a greater setpoint / actual value deviation of the temperature to be regulated. The solenoid valve 18 receives current and opens the refrigerant circuit 16. The pressure increase which then ensues in its low-pressure region 22 actuates the pressure switch 19, the changeover switch 50 being placed on the fixed mating contact 57. As a result, the control device 50 receives voltage via the control line 68 and moves into the switching position in which the compressor runs at the lower speed. The heat pump now emits heat to the heating network 17 via the condenser 12, the additional heating remaining out of operation because of the open contact 65c.

If the outside temperature is low, the heat pump should be the only one cannot cover, the room temperature controller 65 switches to its second Switch-on position in which the switching contact 65b controls the control line 67 of the control unit 50 and the switching contact 65c the line to the solenoid valve 8O closes. As a result, the fuel supply to the heating system 39 is released and its burner via not shown, with the solenoid valve 80 functional coupled funds ignited. At the same time, the switching valve is also activated 29 changed over to the magnet in such a way that at least part of the rotating Heating water passes through the heat exchanger 38 of the heating system 39. By moving the switchover contact 65b and supplying the control unit 50 via the Control line 67, the speed of the compressor is increased and in this way the heat pump is operated in the second power level. With decreasing heat demand The controller 65 first switches the auxiliary heating on the space heaters 31 39 and then the heat pump down or to the first output level return.

To initiate the shutdown process of the heat pump, open the Switching contact 65a, the solenoid valve 18 is closed and thereby the refrigerant circuit 16 interrupted. The compressor 13 continues to run until the pressure in the low pressure area 22 has reached the switching value the pressure switch has lowered ter-s 19 and this switches the switch 55 to the fixed mating contact 56. Only then is the power supply to the drive motor of the compressor finally interrupted. That way is

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ensures that there is no refrigerant when the heat pump is not working can dissolve in the lubricating oil of the compressor, which can lead to liquid hammers or even damage to the valves when the compressor is restarted of the compressor. In the event of leaky valves, the pressure of the refrigerant rises in the lower pressure area 22 of the refrigerant circuit 16 in the work breaks of the heat pump. The pressure switch 19 takes care of this Case in which, with the solenoid valve 18 closed, the compressor goes into operation for a short time and the refrigerant pressure in this area is set to the prescribed level Value decreases or holds at this value for any length of time.

When the power returns after a longer power failure, it could be without additional Aids happen that when the compressor 13 starts up again, the solenoid valve 18 also opens immediately. Then, despite the precaution, which is taken in the normal work breaks of the heat pump for sucking off refrigerant from the low-pressure region 22, those described above cease adverse effects. In order to prevent this, the relay 60 is provided, which holds itself via the switching contact 60b, as long as mains voltage is available. In the event of a power failure, the relay will be 60 de-energized, the switching contacts 60a, 60b and 60c of which open. When the power is restored, the compressor 13 starts immediately because the changeover contact 55 still rests on the mating contact 57. Relay 6O on the other hand initially remains de-energized, so that the solenoid valve 18 also inevitably remains closed because of the open switching contact 60a. That way will even when the compressor is restarted after a power failure, a suction process of the refrigerant from the low-pressure area 22 is forced before the Solenoid valve 18 is opened and the heat pump starts its actual work. If an auxiliary device is not working properly, the switch goes 52 in the open position. As a result, the relay 60 is also de-energized and the auxiliary heating is also shut down via the switching contact 60c, provided that this was switched on when the fault occurred.

When there is a demand for heat from the domestic water thermostat 64, the switching valve 3O via the switch contact 64e and the magnet 42 into the second switch position brought, in which the hot flow water reaches the water tank 44 via the branch line 43. At the same time, the switching contacts

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64a, 64b and 64d are closed and the switching contact 64c is open. This will the refrigeration circuit 16 released, the compressor in operation at increased speed set, and the circulation pump 33 switched on, provided this is in the pure Summer operation was shut down. The heat pump works in this way in the power level 2, the supply of heat to the space heaters 31 being temporarily interrupted. After covering the heat demand of the domestic hot water thermostat 64 switches the system back to the previous operating state.

The switching contact 66b of the Sömmer / Winter switch in the feed line 02 to the solenoid valve 80 the heating system 39 is open in summer mode. This switch contact ensures that the auxiliary heating remains switched off in summer operation, even if the switching contact 65c of the temperature controller closes. The changeover contact 64f of the domestic water thermostat 64 causes the additional heating to be switched off remains when the domestic hot water thermostat 64 calls for heat. This is also desirable because when the domestic hot water thermostat 24 in the second output stage working heat pump alone in most cases sufficient to cover the heat demand. But it also happens that in a short time A very large amount of heated domestic water is to be available for z. B. if a bathtub is to be filled several times in a row. In this case, the invention provides that the additional heating for domestic water heating the heat pump can be switched on at will. Be that way the investment costs of the additional heating are also used more economically, as if the additional heating is only used to cover an increased heat demand on the space radiators on a few days of the year.

When there is a demand for heat from the domestic water thermostat 64, the changeover contact opens 64f to line 83. This line is controlled by the switch contact 86b of the arbitrarily operated switch 86, which is used for the purpose to switch on the additional heating. Doing so will lead 83 closed and all necessary for the additional heating to take effect Switching processes triggered. The switch 86 is expedient with one not shown optical display instrument coupled, which the operator the indicates arbitrary connection of the additional heating.

The switch 86a bypasses the switch contact 60c when the arbitrarily operable one Switch 86 is depressed. As a result, an emergency operation for heating the rooms can be maintained for the duration of the actuation of the switch 86,

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if the heat pump has failed due to a fault and the switching contact as a result 60c is open.

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Claims (7)

Claims Heating system with a heat pump that uses an evaporator heat absorbed from a heat transfer medium such as air or water a condenser in a heating network leading to space heaters promotes, to which also a radiator of a domestic water heater, in particular a domestic water tank via a valve device is connected, which via a thermostat influenced by the temperature of the domestic water in the sense of a priority circuit for domestic water heating is controlled, and furthermore with an additional heater, which can be switched on via a thermostatic controller in the event of increased heat demand on the room radiators, characterized in that that means (86) are provided, via which the auxiliary heater (39) can be switched on regardless of the heat demand on the room radiators (31) when there is a heat demand through the domestic water thermostat (64). 2. Installation according to claim 1, characterized in that the means for switching on the auxiliary heater (39) can be arbitrarily actuated by an operating element (86) when domestic water is heated. 3. Plant according to claim 2, characterized in that the operating member (86) is connected to a switch (86b) in series with one of the Domestic water thermostats (64) influenced switch (64f) leads to a device (36) which controls the operation of the auxiliary heating (39). 4. Plant according to claim 3, characterized in that the domestic water thermostat (64) influences a changeover contact (64f), on whose fixed mating contacts two control lines (82, 83) for the additional heater (39) are connected, the first of which is a switch contact (65c) of the the controller (65) controlling the flow of heat to the space heating elements and the other influencing the control element (86) which can be operated at will Switch contact. (86b) contains. 5. Plant according to claim 4, characterized in that in the first control line (82) the switching contact (66b) of a summer / winter switch (66) is installed. 8U98 0-8 / 0254 - 12 - 6. Installation according to claim 4 or 5, characterized in that a normally open contact (6Oc) of a relay (60) is installed in the first control line (82)
is that when the compressor (13) of the heat pump is restarted when the power is restored after a power failure, a shut-off valve (18) in the refrigerant circuit keeps closed for a while. 7. Plant according to claim 6, characterized in that the working contact
(60c) of the relay (60) is bridged by a contact (86a) of the switch influenced by the arbitrarily operable operating element (86). 809808/0254