JP2018004188A - Hot water heating system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot water heating system capable of suppressing the efficiency deterioration of a defrosting operation.SOLUTION: When it is determined that a defrosting start condition is satisfied during executing a heating operation, a high temperature and high pressure refrigerant is caused to flow into a refrigerant water heat exchanger 10 to thereby heat water in a hot water circuit 3 near the refrigerant water heat exchanger 10 by stopping driving of a circulation pump 12 and also closing thermal valves 13. Since natural circulation due to convection is inhibited because of the closing of the thermal valves 13 even though a difference in a water temperature in the hot water circuit 3 occurs to cause the convection, efficiency deterioration of defrosting can be inhibited without lowering a high temperature and high pressure refrigerant temperature which circulates through a refrigeration circuit 5 in the refrigerant water heat exchanger 10 during a defrosting operation.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a hot water heating system capable of performing heating using hot water exchanged with a heat pump device.

  Conventionally, in this type, a refrigeration circuit and a hot water circuit are provided in a heat source machine installed outdoors, and a high-temperature refrigerant heated in the refrigeration circuit and water in the hot water circuit are heated in a refrigerant water heat exchanger. There is a hot water heating system that allows hot water such as floor heating to be heated by flowing the water in the hot water circuit to a heating terminal by replacing the hot water. When a heating terminal that can be opened and closed is installed in the middle of the pipe and a heating terminal that performs heating operation is selected by the remote control and the start of heating operation is instructed, the thermal operation is performed so that hot water is supplied to the selected heating terminal. Heating operation was enabled by opening the valve and driving each drive component in the refrigeration circuit and the circulation pump in the hot water circuit at a predetermined rotational speed. (For example, Patent Document 1)

JP 2013-234777 A

  However, in this conventional system, when heating operation is performed when the outside air temperature is low, such as in winter, frost adheres to the surface of the air heat exchanger due to moisture in the air passing through the air heat exchanger, Since the heat exchange in the air heat exchanger is hindered by the growth and the efficiency of the heating operation is reduced, the difference between the outside air temperature and the surface temperature of the air heat exchanger becomes a predetermined value or more. When the defrosting start condition is satisfied, it is judged that frost has adhered to the air heat exchanger, the heating operation is stopped, the expansion valve in the refrigeration circuit is fully opened, and the circulation pump in the hot water circuit is stopped. In addition, by performing the defrosting operation for driving the compressor, the frost adhering to the surface of the air heat exchanger was melted by the high-temperature refrigerant that passed through the expansion valve.

  During the defrosting operation, even if the circulating pump on the hot water circuit side is stopped, the water temperature rises due to heat being transferred from the refrigerant to the water in the refrigerant water heat exchanger, and in the vicinity of the refrigerant water heat exchanger in the hot water circuit The water temperature in the refrigerant water heat exchanger is low, the water temperature at a position away from the refrigerant water heat exchanger is low, and a difference in water temperature causes convection and water circulates naturally. Since the heat exchange with the water in the hot water circuit is performed, the temperature of the refrigerant sent to the air heat exchanger is lowered and the efficiency of defrosting is lowered, so there is room for improvement.

In order to solve the above problems, in claim 1 of the present invention, a refrigeration circuit in which a compressor, an expansion valve, an air heat exchanger, and a refrigerant water heat exchanger are connected by a refrigerant pipe;
A hot water circuit in which water heated by the refrigerant water heat exchanger flows;
A heating terminal connected to the hot water circuit via a hot water pipe;
A thermal valve that changes the presence or absence of hot water supply to the heating terminal by opening and closing a valve installed in the middle of the hot water circuit, a circulation pump that is installed in the middle of the hot water circuit and circulates hot water in the piping,
A remote control for instructing the heating terminal to start a heating operation for raising the room temperature by supplying hot water through the hot water circuit and the hot water pipe to the heating terminal;
When it is determined that there is an instruction to start heating operation from the remote controller, the circulating pump is driven and the thermal valve is opened so that hot water is supplied to the heating terminal, and each drive component in the refrigeration circuit is controlled. And a control unit that controls so that a high-temperature refrigerant flows into the refrigerant water heat exchanger,
When it is determined that there has been an instruction to start a defrosting operation for performing defrosting of the air heat exchanger, the control unit closes the thermal valve and stops driving the circulation pump. .

  According to a second aspect of the present invention, when the control unit determines that the defrosting operation end condition is satisfied, the control valve opens the thermal valve and a predetermined time has elapsed since the thermal valve was opened. The circulation pump is driven later.

  According to this invention, when it is determined that there has been an instruction to start the defrosting operation for performing the defrosting of the air heat exchanger, the thermal valve is closed and the circulation pump is stopped. Even if the water temperature in the hot water circuit rises and convection occurs, the circulation of water in the hot water circuit is hindered by closing the thermal valve, so that the refrigerant passing through the refrigerant water heat exchanger The heat is not taken away by the hot water circuit side, and a decrease in defrosting efficiency can be suppressed.

  If it is determined that the defrosting operation termination condition is satisfied, the thermal valve is opened, and the circulation pump is driven after a predetermined time has elapsed since the thermal valve was opened. Since the water in the hot water circuit circulates by convection by the valve, the load of the circulation pump that forcibly circulates the water is reduced, so that the product life of the circulation pump can be extended.

The perspective view which shows one Embodiment of this invention Schematic configuration diagram of the embodiment Control block diagram of the embodiment Timing chart explaining operation at the time of heating operation and defrosting operation of the embodiment

Next, a hot water heating system according to an embodiment of the present invention will be described with reference to the drawings.
Reference numeral 1 denotes a heat source unit of a hot water heating system installed outdoors. The heat source unit 1 has a structure divided into two upper and lower chambers by a horizontal partition plate 2 installed inside. A hot water circuit chamber 4 provided with a hot water circuit 3 constituted by hot water piping through which the refrigerant circulates, and a refrigeration circuit chamber 6 provided with a refrigeration circuit 5 as a heat pump device constituted by refrigerant piping through which refrigerant circulates below are installed. I have.

Reference numeral 7 is a pipe connecting the hot water circuit room 4 and a heating terminal 8 composed of a floor heating panel or the like installed in the room, and the outgoing hot water pipe for feeding the hot water heated by the hot water circuit 3 to the heating terminal 8. , 9 is a return-side hot water pipe for returning the hot water whose temperature has been reduced by heat radiation at the heating terminal 8 to the hot water circuit 3, and the hot water is formed in the hot water pipe constituted by the forward-side hot water pipe 7 and the return-side hot water pipe 9. Circulation enables heating operation by the heating terminal 8.
In addition, the said heating terminal 8 can be installed in each of a plurality of rooms, and the heating terminal 8 is connected to each of the plurality of heating terminals 8 by connecting an outgoing hot water pipe 7 and a return hot water pipe 9 respectively. Heating operation is possible for each of a plurality of rooms in which are installed.

The hot water circuit 3 installed in the hot water circuit chamber 4 includes a refrigerant water heat exchanger 10 for exchanging heat between the refrigerant flowing in the refrigeration circuit 5 and the water flowing in the hot water circuit 3, and hot water by cavitation or the like. A cistern tank 11 that separates bubbles generated in the inside (air / water separation function), absorbs hot and cold water in the hot water circuit 3 and replenishes cold / hot water, and circulates hot water in the hot water circuit 3 to heat the heating terminal via the hot water pipe A circulation pump 12 for supplying hot water to 8, and a thermal valve 13 for changing the presence or absence of supply of hot water to the heating terminal 8 by opening and closing the valve installed at the connection between the hot water circuit 3 and the outgoing hot water pipe 7. A return temperature sensor 14 that detects the temperature of the hot water returned from the heating terminal 8 installed at the connection between the return-side hot water pipe 9 and the hot water circuit 3 and the temperature of the hot water heated by the refrigerant water heat exchanger 10 Outgoing temperature sensor 1 to detect When the refrigerant-water heat exchange sensor 16 for detecting the surface temperature of the installed in the refrigerant-water heat exchanger 10 heat exchanger is disposed in various places.
The thermal valve 13 and the return temperature sensor 14 are installed one by one for each heating terminal 8. For example, if the heating terminal 8 is installed in each of two rooms, One thermal valve 13 and one return temperature sensor 14 are provided for each of the connection portion between the hot water pipe 7 and the return side hot water pipe 10 connected to the terminal 8 and the hot water circuit 3.

  The refrigeration circuit 5 installed in the refrigeration circuit chamber 6 includes a compressor 17 that compresses the refrigerant to a high temperature and a high pressure, an expansion valve 18 that decompresses the refrigerant to a low temperature refrigerant, and a blower fan 19. The air heat exchanger 20 that heats the refrigerant with the heat of the blown air, the air heat exchange sensor 21 that is installed in the air heat exchanger 20 to detect the surface temperature of the heat exchanger, and is compressed by the compressor 17. Discharge temperature sensors 22 for detecting the temperature of the refrigerant are arranged at various places, and the refrigerant discharged from the compressor 17 is supplied to the refrigerant water heat exchanger 10 in the hot water circuit chamber 4 via the refrigerant connection valve 23. And the refrigerant that has exchanged heat with the hot water in the hot water circuit 3 in the refrigerant water heat exchanger 10 flows into the expansion valve 18 via the refrigerant connection valve 23 so that the refrigerant in the refrigerant circuit 5 circulates. It has become.

  The refrigeration circuit chamber 6 is provided with an outside air temperature sensor 24 for detecting the temperature around the heat source 1, and the difference between the temperature detected by the air heat exchange sensor 21 and the temperature detected by the outside air temperature sensor 24 is detected. Based on this, the presence or absence of defrosting operation is determined.

  Reference numeral 25 denotes a remote controller installed on a wall or the like of the room where the heating terminal 8 is arranged. The remote controller 25 includes an operation switch 26 that can determine whether or not the heating operation by the heating terminal 8 is started, and the room during the heating operation. A temperature setting switch 27 that can be selected from a plurality of set values, and a display 28 that displays the presence or absence of heating operation, the current set temperature, and the like are provided.

  Reference numeral 29 denotes a control unit composed of a microcomputer for controlling the operation of drive parts such as the circulation pump 12 and the heat valve 13 installed in the heat source unit 1. When the remote controller 25 gives an instruction to start the heating operation Depending on the temperature detected by the return temperature sensor 14, the forward temperature sensor 15, etc., the presence / absence of driving of the circulation pump 12 and the opening / closing of the thermal valve 13 are appropriately executed.

  Reference numeral 30 denotes a signal line that connects the remote controller 25 and the control unit 29 with electrical wiring, and enables various instructions issued by the remote control 25 to be transmitted to the control unit 29 with electrical signals.

  Reference numeral 31 denotes a power line for supplying power to the heat source unit 1 from a commercial power source (not shown) indoors or outdoors.

Next, the operation | movement at the time of the heating operation in this embodiment is demonstrated.
First, when the operation switch 26 of the remote controller 25 in the room where the heating terminal 8 is installed is operated, the control unit 29 compresses based on the temperature detected by the air heat exchange sensor 21 and the discharge temperature sensor 22 of the refrigeration circuit 5. The refrigerant discharged from the compressor 17 is supplied to the refrigerant water heat exchanger 10 by driving the compressor 17 and the blower fan 19 at a predetermined rotational speed and controlling the opening degree of the expansion valve 18 to be a predetermined opening degree. The expansion valve 18 and the air heat exchanger 20 are circulated in this order.

  Thereby, after the refrigerant in the gas state sucked at low temperature and low pressure is compressed by the compressor 17 to become high temperature and high pressure gas, the hot water circuit 3 in the refrigerant water heat exchanger 10 (functions as a condenser). It changes into a high-pressure liquid while releasing heat to the water inside. The refrigerant that has become liquid in this manner is decompressed by the expansion valve 18 to become a low-pressure liquid and is easily evaporated. Thereafter, the low-pressure liquid evaporates in the air heat exchanger 20 (functions as an evaporator) and changes into gas, thereby absorbing heat from the outside air. Then, the refrigerant again flows into the compressor 17 as a low temperature / low pressure gas and changes to a high temperature / high pressure gas.

At this time, when the circulation pump 12 in the hot water circuit 3 is driven, the hot water in the hot water circuit 3 heated by the refrigerant water heat exchanger 10 is routed to the heating terminal 8 that performs the heating operation. Since the thermal valve 13 is opened so that warm water flows into the side warm water pipe 7, warm water flows into the heating terminal 8, dissipates heat to the room air, raises the room temperature, and then the coolant water heat It passes through the exchanger 10 and the cistern tank 11 and returns to the circulation pump 12 again.
As described above, the hot water in the hot water circuit 3 and the refrigerant in the refrigeration circuit 5 circulate, whereby the water in the hot water circuit 3 is heated by the refrigerant water heat exchanger 10 and the room air in which the heating terminal 8 is installed. It becomes possible to carry out a heating operation that raises the temperature of the.

Next, the operation of the circulation pump 12 and the thermal valve 13 when changing the operation from the heating operation to the defrosting operation of the present embodiment will be described based on the timing chart of FIG.
First, when the operation switch 26 of the remote controller 25 is operated and a heating operation is performed to increase the temperature of the indoor air by flowing hot water into the heating terminal 8, the control unit 29 performs an outside temperature in winter or the like. The temperature detected by the outside air temperature sensor 24 is lower than the predetermined temperature, the difference between the temperature detected by the outside air temperature sensor 24 and the temperature detected by the air heat exchange sensor 21 exceeds a predetermined value, or compression It is determined whether a defrosting start condition such as that the accumulated time of the machine 17 has reached a predetermined time or more is satisfied.

  If it is determined that the defrosting start condition is satisfied, the temperature around the air heat exchanger 20 is low and moisture in the air adheres to the fins as frost, and the heat exchange efficiency in the air heat exchanger 20 decreases. Therefore, on the hot water circuit 3 side, the control unit 29 controls the circulation pump 12 to stop and closes all the thermal valves 13 that are currently open, and the refrigeration circuit 5 side. Then, the compressor 17 is driven at a predetermined rotational speed, the blower fan 19 is stopped, and the opening degree of the expansion valve 18 is controlled to be fully opened. The frost adhering to the fins of the air heat exchanger 20 is melted by flowing into the air heat exchanger 20 sequentially through the refrigerant water heat exchanger 10 and the expansion valve 18.

  At this time, the circulation pump 12 of the hot water circuit 3 is stopped and all the thermal valves 13 are closed, so that the high-temperature and high-pressure refrigerant passes through the refrigerant water heat exchanger 10 and the hot water circuit 3. The heat is released to the side, the water temperature in the vicinity of the refrigerant water heat exchanger 10 rises, and a temperature difference is created in the water temperature in the hot water circuit 3, and convection occurs, and the refrigerant water heat exchanger 10 and the heating terminal 8 are installed. When there is a difference in height (for example, the heat source device 1 having the refrigerant water heat exchanger 10 is installed on the first floor of the house, the heating terminal 8 is installed on the second floor of the house, etc.) Even if the water is to be circulated, since the circulation of the water in the hot water circuit 3 is obstructed because the thermal valve 13 is closed, the low temperature hot water does not flow into the refrigerant water heat exchanger 10. The temperature drop of the high-temperature and high-pressure refrigerant can be prevented, and the air heat exchanger 20 is efficiently heated. It is possible, it becomes possible to suppress a decrease in defrosting efficiency.

  Then, if it is determined that the defrosting operation end condition such as the temperature detected by the air heat exchange sensor 21 has reached a predetermined value or more, or the defrosting operation has been performed for a predetermined time or more, the control is performed. The unit 29 opens the thermal valve 13 that was opened before the start of the defrosting operation, and if it is determined that a predetermined time of 40 seconds has elapsed since the thermal valve 13 is opened, the circulation is performed. By driving the pump 12 at a predetermined number of revolutions, the heating operation performed before the defrosting operation is started is resumed.

  At this time, immediately after the end of the defrosting operation, convection is generated due to a temperature difference in the water temperature in the hot water circuit 3, and water is easily circulated in the pipe. Immediately after the valve 13 is opened, the water in the outgoing hot water pipe 7 and the return hot water pipe 9 starts to flow slowly, and the circulating pump 12 is driven after 40 seconds from the opening of the thermal valve 13. By starting, since the water in the hot water pipe 3 flows by natural circulation due to convection, the load on the circulation pump 12 is reduced and the product life is improved.

  As described above, when it is determined that the defrosting start condition is satisfied when the heating operation is performed, the coolant water heat exchange is performed by stopping the operation of the circulation pump 12 and closing the opened thermal valve 13. Even if high-temperature and high-pressure refrigerant flows into the vessel 10, the water in the hot water circuit 3 near the refrigerant water heat exchanger 10 is heated, and even if convection occurs due to a difference in the water temperature in the hot water circuit 3, Since the natural circulation by convection is hindered by closing the thermal valve 13, the temperature of the high-temperature and high-pressure refrigerant circulating through the refrigeration circuit 5 in the refrigerant water heat exchanger 10 is reduced during the defrosting operation. Therefore, it is possible to suppress a decrease in defrosting efficiency.

  When the defrosting operation end condition is satisfied, the circulation pump 12 is turned on after a predetermined time of 40 seconds has elapsed since the thermal valve 13 is opened so as to be in the heating operation state before the defrosting operation is started. Since the water temperature in the hot water circuit 3 is different due to the defrosting operation and the water in the hot water circuit 3 naturally flows by convection immediately after the thermal valve 13 is opened, the water in the hot water circuit 3 flows. By driving the circulation pump 12 after natural flow, the load on the circulation pump 12 can be reduced and the product life can be improved.

  The other configurations used in the present embodiment are presented as examples, and are not intended to limit the scope of the invention, and can be implemented in various other forms. Although the terminal 8 has been described by taking only the floor warming panel as an example, a hot water room heater or other dedicated terminal having a heating function may be applied, and various omissions, replacements, and changes may be made without departing from the scope of the invention. It can be performed. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 Heat source machine 3 Hot water circuit 5 Refrigeration circuit 7 Outward side hot water piping 8 Heating terminal 9 Return side hot water piping 10 Refrigerant water heat exchanger 12 Circulation pump 13 Thermal valve 17 Compressor 18 Expansion valve 20 Air heat exchanger 25 Remote control 29 Control Part

Claims (2)

A refrigeration circuit in which a compressor, an expansion valve, an air heat exchanger and a refrigerant water heat exchanger are connected by refrigerant piping;
A hot water circuit in which water heated by the refrigerant water heat exchanger flows;
A heating terminal connected to the hot water circuit via a hot water pipe;
A thermal valve that changes the presence or absence of hot water supply to the heating terminal by opening and closing a valve installed in the middle of the hot water circuit, a circulation pump that is installed in the middle of the hot water circuit and circulates hot water in the piping,
A remote control for instructing the heating terminal to start a heating operation for raising the room temperature by supplying hot water through the hot water circuit and the hot water pipe to the heating terminal;
When it is determined that there is an instruction to start heating operation from the remote controller, the circulating pump is driven and the thermal valve is opened so that hot water is supplied to the heating terminal, and each drive component in the refrigeration circuit is controlled. And a control unit that controls so that a high-temperature refrigerant flows into the refrigerant water heat exchanger,
When it is determined that there is an instruction to start a defrosting operation for performing defrosting of the air heat exchanger, the control unit closes the thermal valve and stops driving the circulation pump. Hot water heating system.   When it is determined that the defrosting operation end condition is satisfied, the control unit opens the thermal valve and drives the circulation pump after a predetermined time has elapsed since opening the thermal valve. The hot water heating system according to claim 1.

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