JP7368307B2 - heating system - Google Patents

Description

The present invention relates to a heating system using multiple heat sources.

The present applicant previously disclosed in the following Patent Document 1 a heating terminal, a circulation circuit that circulates a heat medium to the heating terminal, a heat pump type heat source device that heats the heat medium circulating in the circulation circuit, and a heating terminal that circulates the heat medium in the circulation circuit. The hot water storage type combustion heat source device is equipped with a hot water storage type combustion heat source device that heats a heating medium, and performs heating operation by a heating terminal using the heating medium, and the hot water storage type combustion heat source device is equipped with a storage can body that stores the heating medium inside. and a vaporizing burner that heats the heat medium in the storage can, and the hot water storage type combustion heat source device is installed downstream of the heat pump type heat source device with respect to the flow of the heat medium circulating in the circulation circuit. We provided a unique heating system.

Patent Application No. 2019-31735

By the way, with this conventional system, heating operation is possible with only one of the hot water storage type combustion heat source equipment and the heat pump type heat source equipment operating, and predetermined conditions are met during this heating operation. In this case, the heat source device is switched, and the heat source device that was operating until then is stopped, and the heat source device that was stopped until then is started operating.

Here, a vaporization burner with a vaporizer that vaporizes fuel is used as the combustor of the hot water storage type combustion heat source device, and during heating operation with only the hot water storage type combustion heat source device operating, the hot water storage type combustion heat source device Consider the case where the heat source device is switched to a heat pump type heat source device. At this time, the hot water storage type combustion heat source device is stopped, the heat pump type heat source device starts operating, and the heating of the heat medium by the heat pump type heat source device is started immediately. The start-up of the heat pump type heat source device is completed before the temperature of the heat medium drops significantly. Therefore, the temperature drop of the heat medium supplied to the heating terminal after switching the heat source device is small.

Next, consider a case where the heat source device is switched from the heat pump type heat source device to the hot water storage type combustion heat source device during heating operation with only the heat pump type heat source device operating. Since the hot water storage type combustion heat source equipment uses a vaporization burner having a vaporizer that vaporizes fuel as a combustor, combustion starts after preheating the vaporizer for a certain period of time. In this case, after the heat pump type heat source device stops, the heating medium in the storage can cannot be heated immediately by the hot water storage type combustion heat source device, and the temperature of the heating medium decreases significantly. As a result, the temperature of the heat medium supplied to the heating terminal after switching the heat source device increases.

As mentioned above, when switching heat source equipment, the operation start timing of the heat source equipment that had been stopped until then and the stop timing of the heat source equipment that had been operating until then can be changed from the hot water storage type combustion heat source equipment to the heat pump. If the pattern for switching to a type heat source device is the same as the pattern for switching from a heat pump type heat source device to a hot water storage type combustion heat source device, the temperature of the heat medium supplied to the heating terminal may drop significantly after switching the heat source device. This has caused problems in that stable operation cannot be achieved and the usability is impaired.

In order to solve the above problems, the present invention provides a heating terminal, a circulation circuit that circulates a heat medium to the first heating terminal, a heat pump type heat source device that heats the heat medium circulating in the circulation circuit, A hot water storage type combustion heat source device that heats a heat medium circulating in a circuit , and a control means for controlling the heat pump type heat source device and the hot water storage type combustion heat source device, the heating operation by the heating terminal using the heat medium is provided. The hot water storage type combustion heat source device is equipped with a storage can that stores a heat medium inside the storage can and a vaporization burner that heats the heat medium inside the storage can. The control means is arranged downstream of the heat pump type heat source device with respect to the flow of refrigerant circulating through the heat pump type heat source device, and the control means stops the hot water storage type combustion heat source device from a state in which only the hot water storage type combustion heat source device is operated. The heat pump type heat source device and the hot water storage type combustion heat source device differ depending on whether the heat source device is started, or when only the heat pump type heat source device is in operation, and then the heat pump type heat source device is stopped and the hot water storage type combustion heat source device is started. The overlapping time for each operation is set separately and controlled.

According to claim 1 of the present invention, the device is equipped with a heat pump type heat source device and a hot water storage type combustion heat source device, and performs heating operation by a heating terminal using a heat medium, and only the hot water storage type combustion heat source device is operated. When the hot water storage type combustion heat source device is stopped and the heat pump type heat source device starts operating, and when the heat pump type heat source device is stopped and the hot water storage type combustion heat source device is started from a state where only the heat pump type heat source device is operating. Therefore, we set separate times for the operations of the heat pump type heat source equipment and the hot water storage type combustion heat source equipment to overlap, and from the state where only the hot water storage type combustion heat source equipment is operating, the hot water storage type combustion heat source equipment is stopped and the heat pump type heat source equipment is started. The operation of the heat pump heat source machine and the hot water storage combustion heat source machine will be overstated when the heat pump heat source machine is stopped and the hot water storage combustion heat source machine is started from a state where only the heat pump heat source machine is operating, compared to when the heat pump heat source machine starts operating. By controlling the wrapping time using a long time, when only the heat pump type heat source device is operating, when the heat pump type heat source device is stopped and the hot water storage type combustion heat source device is started, the hot water storage type combustion heat source This machine can prevent the temperature of the heat medium circulating in the circulation circuit from dropping significantly during preheating of the vaporizer that vaporizes fuel, and can be used to switch from a state in which only the hot water storage type combustion heat source unit is in operation to a hot water storage type combustion heat source unit. When the heat pump type heat source device is stopped and started operating, the heat medium circulating in the circulation circuit is not overheated, so stable operation is possible and comfort is not impaired.

1 is a schematic configuration diagram of a heating system in an embodiment of the present invention. FIG. 1 is a schematic configuration diagram of an evaporative burner of a heating system in an embodiment of the present invention. 5 is a time chart illustrating a change in temperature of a heat medium over time when a heat source device that operates independently is switched during heating operation in the first embodiment of the present invention. FIG. 7 is a time chart illustrating a change in temperature of a heat medium over time when a heat source device that operates independently is switched during heating operation in the second embodiment of the present invention. FIG.

Next, the configuration of a heating system 1 according to an embodiment of the present invention will be described based on the drawings. As shown in FIG. 1, the heating system 1 mainly includes a heat pump type heat source device 2, a hot water storage type combustion heat source device 3, and a heating terminal 4. The heating system 1 uses a heat medium (for example, water or a circulating liquid such as antifreeze) heated by at least one of the heat pump type heat source device 2 or the hot water storage type combustion heat source device 3 to generate the heat medium at the heating terminal 4. By dissipating heat from the heating terminal 4, a heating operation is performed to warm the air-conditioned space in which the heating terminal 4 is installed.

The heat pump type heat source device 2 is a heat source device for heating a heat medium, and its housing includes a variable rotation speed compressor 5 for compressing the refrigerant, a four-way valve 6 as a flow path switching means, and a device for connecting the refrigerant and the heat medium. A liquid refrigerant heat exchanger 7 as a load side heat exchanger that exchanges heat, an expansion valve 8 as a pressure reducer, and a heat source side heat exchanger that exchanges heat with the air (outside air) sent by the operation of the outdoor fan 9. The air heat exchanger 10 is connected in an annular manner by a refrigerant pipe 11 to form a heat pump circuit 12 in which the refrigerant circulates. Note that 13 is an outside air temperature sensor that detects outside air temperature.

The liquid refrigerant heat exchanger 7 is configured, for example, by a plate heat exchanger, in which a plurality of heat transfer plates are stacked, and a refrigerant flow path through which a refrigerant flows and a heat medium through which a heat medium flows. Heat medium flow paths are formed alternately with each heat transfer plate as a boundary. As the refrigerant that circulates in the heat pump circuit 12, any refrigerant such as HFC refrigerant or carbon dioxide refrigerant can be used.

The four-way valve 6 provided in the refrigerant pipe 11 has the function of switching the flow direction of the refrigerant in the heat pump circuit 12, and transfers the refrigerant discharged from the compressor 5 to the liquid refrigerant heat exchanger 7, the expansion valve 8, and the air heat A state in which the refrigerant is passed through the exchanger 10 in order and forms a flow path returning to the compressor 5 (state during heating operation), and a state where the refrigerant discharged from the compressor 5 is passed through the air heat exchanger 10, the expansion valve 8, and the liquid refrigerant. It is possible to switch between a state (a state during defrosting operation) in which a flow path is formed in which the air flows through the heat exchanger 7 and returns to the compressor 5.

The hot water storage type combustion heat source device 3 is a heat source device for heating a heat medium, and in its housing is a combustor that burns fuel (gas, kerosene, etc.) by receiving combustion air from the blower fan 14. A hot water storage heat exchanger 16 that recovers heat from the combustion gas generated by combustion of the vaporization burner 15 and heats a heat medium, and a hot water storage heat exchanger 16 adjacent to the upper part of the hot water storage heat exchanger 16. It has an exhaust chamber 17 that collects the combustion gas after passing through the exhaust chamber 16, and an exhaust pipe 18 that discharges the combustion gas after passing through the exhaust chamber 17 to the outside of the machine.

The hot water storage heat exchanger 16 includes a cylindrical, small-capacity storage can 19 that stores a certain amount (4 L to 10 L) of heat medium therein, and a evaporative burner 15 that is formed inside the lower part of the storage can 19 for combustion. The combustion chamber 20 is composed of a combustion chamber 20 in which combustion occurs, and a plurality of smoke pipes 21 that connect the combustion chamber 20 and the exhaust chamber 17 and allow combustion gas generated by combustion in the vaporization burner 15 to pass therethrough. Note that 22 is a first heat medium temperature sensor serving as a first temperature detection means for detecting the temperature of the heat medium within the storage can body 19. Note that the first heat medium temperature sensor 22 does not have to be installed directly in the storage can body 19, but can detect the temperature of the heat medium flowing out from the storage can body 19 and flowing into the heating terminal 4. It's okay.

Here, to explain the vaporization burner 15, as shown in FIG. 2, there is a vaporizer 35 that vaporizes fuel oil as fuel, and a vaporizer provided in the vaporizer 35 that heats the vaporizer 35 to a temperature at which fuel oil can be vaporized. A heater 37, a vaporization temperature sensor 36 that detects the temperature of the vaporizer 35, a mixing chamber 38 that communicates with the vaporizer 35 and premixes the vaporized gas vaporized in the vaporizer 35 and primary air, and a bottom part of the mixing chamber 38. A mixing chamber heater 39 is provided to heat the mixing chamber 38, a mixing chamber temperature sensor 40 detects the temperature of the mixing chamber 38, and a mixing chamber temperature sensor 40 communicates with the mixing chamber 38 to burn the premixed gas premixed in the mixing chamber 38. A plurality of heat absorption fins 42 protruding above the combustion section 41 on the back surface of the vaporizer 35 feed back combustion heat to the vaporization heater 37 and the mixing chamber heater 39. This is to suppress the amount of current applied as much as possible.

The vaporizing burner 15 also includes a nozzle 43 that sprays fuel into the vaporizer 35, and an electromagnetic pump 45 that pumps fuel into the nozzle 43 through an oil feed pipe 44. communicates with the air chamber 48 between the combustion part 41 and the cover frame 47, and supplies the combustion air sucked by the blower fan 14 through the suction port 49 to the carburetor 35 as primary air for premixing; The air chamber 48 is supplied with secondary air that passes through the side of the carburetor 35 and is combusted in the combustion section 41 from below the mixing chamber 38 .

Subsequently, as shown in FIG. 1, the circulation circuit 23 that circulates the heat medium to the heating terminal 4 transfers the heat medium flowing out from the heating terminal 4 to the heat medium flow path of the liquid refrigerant heat exchanger 7 of the heat pump type heat source device 2. A first heat medium pipe 24 that guides the heat medium flowing out from the liquid refrigerant heat exchanger 7 of the heat pump type heat source device 2 to the hot water storage type heat exchanger 16 (storage can body 19) of the hot water storage type combustion heat source device 3. 2 heat medium pipe 25 and a third heat medium pipe 26 that guides the heat medium flowing out from the hot water storage type heat exchanger 16 (storage can body 19) of the hot water storage type combustion heat source device 3 to the heating terminal 4, and has a circulation circuit. 23 connects the heat pump type heat source device 2, the hot water storage type combustion heat source device 3, and the heating terminal 4 through a first heat medium pipe 24, a second heat medium pipe 25, and a third heat medium pipe 26, so that the heat medium circulates. It is formed to do so. The hot water storage type combustion heat source device 3 is disposed downstream of the heat pump type heat source device 2 with respect to the flow of the heat medium circulating through the circulation circuit 23 .

The first heat medium pipe 24 is provided with a circulation pump 27 that circulates the heat medium in the circulation circuit 23, and is also provided with a heat pump side cistern 28 that stores the heat medium and adjusts the pressure of the circulation circuit 23.

The second heat medium pipe 25 has a second temperature that detects the temperature of the heat medium flowing out from the liquid refrigerant heat exchanger 7 of the heat pump type heat source device 2 and flowing into the hot water storage type heat exchanger 16 of the hot water storage type combustion heat source device 3. A second heat medium temperature sensor 29 is provided as a detection means.

The third heat medium pipe 26 is provided with a combustion side cistern 30 that stores a heat medium and adjusts the pressure of the circulation circuit 23 .

Further, each of the third heat medium pipes 26 branched for each heating terminal 4 is provided with a thermal valve 31 that controls the supply of heat medium to the heating terminal 4 by opening and closing the third heat medium pipe 26. Opening/closing is controlled so that the temperature of the air-conditioned space (indoor) in which the heating terminal 4 is installed reaches a predetermined temperature, or so that the temperature of the heat medium returned from the heating terminal 4 reaches a predetermined temperature. . The heating terminal 4 can be any terminal such as a floor heating panel or a radiator, and although two are provided in FIG. 1, it may be one, three or more, and the quantity may vary. The specifications are not particularly limited.

Reference numeral 32 denotes a remote control for instructing the operation of the heating system 1, and the remote control 32 includes an operation switch for instructing the heating terminal 4 to start or stop heating operation, and a temperature setting for setting the target temperature of the heat medium circulating in the circulation circuit 23. It is equipped with a switch, a display section, etc.

33 is a heat pump side control device that controls the operation of the heat pump type heat source device 2, and includes a storage device (ROM, nonvolatile memory, etc.) for storing various data and programs, and a control device for performing arithmetic and control processing. The heat pump side control device 33 receives signals from the remote controller 32, the outside air temperature sensor 13, and the second heat medium temperature sensor 29, and controls the operation of actuators such as the compressor 5 and the circulation pump 27, as well as the operations described below. It is communicably connected to the combustion side control device 34 of the hot water storage type combustion heat source device 3, and can exchange signals such as operation instructions with the combustion side control device 34.

34 is a combustion-side control device that controls the operation of the hot water storage type combustion heat source device 3, which is equipped with storage means (ROM, nonvolatile memory, etc.) for storing various data and programs, and control means for performing arithmetic and control processing. The combustion side control device 34 receives the signal from the first heat medium temperature sensor 22, controls the operation of the ventilation fan 14 and the vaporization burner 15, and is communicably connected to the heat pump side control device 33. It is something.

Next, the operation during heating operation in the heating system 1 of this embodiment will be explained. Heating operation that generates a high-temperature heat medium to be supplied to the heating terminal 4 is performed by operating either the heat pump type heat source device 2 or the hot water storage type combustion heat source device 3 alone, or by operating the heat pump type heat source device 2 and the hot water storage type combustion heat source device 3 alone. In some cases, both hot water storage type combustion heat source devices 3 are operated.

First, to explain the case where heating operation is performed by operating only the heat pump type heat source device 2, the case where an instruction is given from the remote controller 32 to heat the room as an air-conditioned space by the heating terminal 4, and the heat pump type heat source device 2 is activated. The heat pump side control device 33 switches the flow path so that the four-way valve 6 is in the heating operation state, drives the compressor 5, the expansion valve 8, the outdoor fan 9, and the circulation pump 27, and starts the heating operation. let At this time, the thermal valve 31 corresponding to the heating terminal 4 where the heating operation is performed is also opened.

During heating operation, in the heat pump circuit 12, a high-temperature, high-pressure gaseous refrigerant compressed by the compressor 5 is discharged from the compressor 5, and the refrigerant is circulated through the liquid refrigerant heat exchanger 7, which functions as a condenser. It exchanges heat with the heating medium flowing through the heating medium 23, releases heat to the heating medium, and heats the heating medium, changing into a high-pressure refrigerant in a gas-liquid mixed state. The refrigerant in this state is then depressurized in the expansion valve 8 to become a low-pressure refrigerant that easily evaporates, and in the air heat exchanger 10 functioning as an evaporator, it exchanges heat with outside air sent by the operation of the outdoor fan 9. The refrigerant absorbs heat from the outside air, becomes a low-temperature, low-pressure gaseous refrigerant, and returns to the compressor 5 again.

In the circulation circuit 23, the low-temperature heat medium that flows into the liquid refrigerant heat exchanger 7 by the driving of the circulation pump 27 driven at a constant rotation speed is heat exchanged with the refrigerant in the liquid refrigerant heat exchanger 7 that functions as a condenser. After being heated, it passes through the hot water storage type heat exchanger 16 of the hot water storage type combustion heat source device 3 without being heated, and is then supplied to the heating terminal 4, used for indoor heating, and distributed through the heating terminal 4. The heat medium whose temperature has been lowered due to heat dissipation returns to the liquid refrigerant heat exchanger 7 again. At this time, the heat medium heated by the heat pump heat source device 2 is stored in the hot water storage type heat exchanger 16 (storage can body 19) of the hot water storage type combustion heat source device 3, and the hot water storage type heat exchanger 16 (storage can body As long as the heat pump type heat source device 2 is in operation, the temperature of the heat medium in 19) is maintained at approximately the same temperature as the target temperature.

Note that during the heating operation, the heat pump side control device 33 controls the rotation speed of the compressor 5 according to the detected value of the second heat medium temperature sensor 29. Here, the rotation speed of the compressor 5 is set such that the temperature of the heat medium detected by the second heat medium temperature sensor 29 reaches a target temperature determined based on a set temperature set by the user with the remote control 32, for example. control.

Further, the heat pump side control device 33 controls the valve opening degree of the expansion valve 8 according to the discharge temperature of the refrigerant discharged from the compressor 5. Here, the valve opening degree of the expansion valve 8 is controlled so that the discharge temperature of the refrigerant discharged from the compressor 5 becomes a control target refrigerant discharge temperature corresponding to the set temperature of the remote controller 32, for example.

Furthermore, the heat pump side control device 33 controls the rotation speed of the outdoor fan 9 according to the outside air temperature detected by the outside air temperature sensor 13.

Next, a case will be described in which heating operation is performed by operating only the hot water storage type combustion heat source device 3. An instruction is given from the remote controller 32 to heat the room as an air-conditioned space by the heating terminal 4, and the heating operation is performed via the heat pump side control device 33. When the combustion-side control device 34 receives the instruction and the hot water storage type combustion heat source device 3 operates, the combustion-side control device 34 controls the vaporization burner 15 to operate the vaporization burner 15 based on the temperature detected by the vaporization temperature sensor 36. A standby state is entered in which the temperature of the vaporizer 35 is maintained at a temperature at which fuel can be vaporized, for example, the temperature of the vaporizer 35 is maintained at 220° C. to 250° C., and the temperature of the mixing chamber 38 is maintained at 125° C. to 130° C. Thereafter, the blower fan 14 and the electromagnetic pump 45 are driven to cause combustion to occur in the vaporization burner 15, and the circulation pump 27 is driven to start heating operation. At this time, the thermal valve 31 corresponding to the heating terminal 4 where the heating operation is performed is also opened.

During the heating operation, the combustion side control device 34 controls the temperature of the heat medium in the storage can body 19 detected by the first heat medium temperature sensor 22 to reach the target temperature determined based on the set temperature set by the remote controller 32. The control is performed by executing or stopping the combustion of the evaporative burner 15 and adjusting the combustion amount.When starting heating operation, the evaporative burner 15 is controlled so that the temperature of the heat medium quickly rises to the target temperature. The combustion amount is set to a preset upper limit combustion amount, and then, as the temperature of the heat medium approaches the target temperature, the combustion amount of the vaporization burner 15 is gradually lowered to maintain the temperature of the heat medium at the target temperature. If possible, combustion is performed by lowering the combustion amount to a preset lower limit combustion amount, and when the temperature of the heat medium reaches a combustion off temperature that is a predetermined temperature higher than the target temperature, combustion in the vaporization burner 15 is stopped. The standby state is entered. After that, when the temperature of the heating medium reaches the target temperature or the combustion-on temperature which is a predetermined temperature lower than the target temperature, the combustion of the vaporizing burner 15 is restarted, and the heating medium in the storage can body 19 is burned in order to bring the temperature of the heating medium in the storage can body 19 closer to the target temperature. The amount is controlled appropriately. At this time, the standby state continues as long as the remote controller 32 instructs the heating terminal 4 to heat the room as an air-conditioned space, and the combustion side control device 34 receives the instruction via the heat pump side control device 33. be done. Further, if there is no heating instruction from the remote controller 32, the standby state is ended and the operation of the hot water storage type combustion heat source device 3 is stopped.

In the circulation circuit 23, the low-temperature heat medium that flows out of the heating terminal 4 by the circulation pump 27 driven at a constant rotation speed passes through the liquid refrigerant heat exchanger 7 of the heat pump type heat source device 2 without being heated. After being heated by exchanging heat with the combustion gas in the hot water storage type heat exchanger 16 of the hot water storage type combustion heat source device 3, it is supplied to the heating terminal 4 and used for indoor heating, and the heat is radiated as it flows through the heating terminal 4. The heat medium whose temperature has been lowered through the liquid refrigerant heat exchanger 7 passes through the liquid refrigerant heat exchanger 7 again without being heated, and returns to the hot water storage type heat exchanger 16.

Next, the heating load was large and the output was insufficient to operate either the heat pump type heat source device 2 or the hot water storage type combustion heat source device 3, so both the heat pump type heat source device 2 and the hot water storage type combustion heat source device 3 were operated. To explain the case where the heating operation is performed by operating both the heat pump type heat source device 2 and the hot water storage type combustion heat source device 3 to perform the heating operation, the first heat medium temperature sensor 22 of the hot water storage type combustion heat source device 3 is operated. The heat pump side control device 33 and the combustion side control device 34 cooperate with each other as necessary so that the temperature of the heating medium detected by the heating medium reaches the target temperature determined based on the set temperature set by the remote control 32. At the same time, the rotation speed of the compressor 5 is controlled and the evaporative burner 15 is also controlled.

In the circulation circuit 23, the low-temperature heat medium that flows into the liquid refrigerant heat exchanger 7 by the circulation pump 27 driven at a constant rotation speed is heated by exchanging heat with the refrigerant in the liquid refrigerant heat exchanger 7. In the hot water storage type heat exchanger 16 of the hot water storage type combustion heat source device 3, heat is exchanged with the combustion gas and further heated.The heated heat medium is then supplied to the heating terminal 4 and used for indoor heating. The heat medium whose temperature has been lowered due to heat dissipation while flowing through the terminal 4 returns to the liquid refrigerant heat exchanger 7 again.

Here, regarding the heating operation performed by operating either the heat pump type heat source device 2 or the hot water storage type combustion heat source device 3, the judgment for determining which heat source device to operate preferentially is based on the outside air temperature or This is done based on the outside air temperature and the cost for operating the heat source device (the electricity bill for the heat pump type heat source device 2, the fuel cost for the hot water storage type combustion heat source device 3). Specifically, the operating costs of the heat pump type heat source device 2 and the hot water storage type combustion heat source device 3 are compared, and the one with the lowest operating cost is set as the heat source device to be operated preferentially, and the other is set as the heat source device to be operated auxiliary. The operating cost of the heat pump type heat source device 2 is the thermal efficiency (coefficient of performance) according to the outside air temperature, the thermal efficiency (coefficient of performance) according to the outside air temperature, the fixed electricity bill regardless of the time of day, or the outside air temperature. The operating cost of the hot water storage type combustion heat source device 3 is calculated based on the thermal efficiency or the thermal efficiency and the fuel cost.

For example, if the outside air temperature fluctuates (the outside air temperature decreases) during heating operation with only the heat pump heat source device 2 in operation, the heat source for heating the heat medium changes from the heat pump heat source device 2 to the hot water storage combustion heat source device. 3, and conversely, if the outside air temperature fluctuates (the outside air temperature rises) during heating operation with only the hot water storage type combustion heat source device 3 in operation, the hot water storage type combustion heat source device 3 is switched to the heat pump type heat source device. It can be switched to 2.

Next, in the first embodiment, the time course of the heat medium temperature in the case where the heat pump type heat source device 2 is switched to the heat pump type heat source device 2 during heating operation with only the hot water storage type combustion heat source device 3 in operation is shown in FIG. 3. This will be explained using a chart. In FIG. 3, a solid line indicates the temporal change in the temperature of the heat medium supplied to the heating terminal 4 (the temperature of the heat medium detected by the first heat medium temperature sensor 22) in the first embodiment. Note that the time t1 represents the time when heating operation is performed by operating only the hot water storage type combustion heat source device 3, and a stable state is reached after a certain period of time has passed.

From time t1 to t2, heating operation is performed by operating only the hot water storage type combustion heat source device 3, and the target temperature of the heat medium supplied to the heating terminal 4 is set at 50°C. The combustion of the evaporative burner 15 is performed so that the temperature of the heat medium detected by the first heat medium temperature sensor 22 of the type combustion heat source device 3 reaches the target temperature determined based on the set temperature set with the remote controller 32. The amount is controlled. At this time, the temperature of the heat medium in the circulation circuit 23 (storage can body 19, third heat medium pipe 26) from the storage can body 19 of the hot water storage type combustion heat source device 3 to the inlet of the heating terminal 4 is the target temperature ( 50°C).

Then, at time t2, when the hot water storage type combustion heat source device 3 is switched to the heat pump type heat source device 2 due to fluctuations in the outside air temperature, etc., heating is continued until the heating output of the heat pump type heat source device 2 stabilizes after time t2. The temperature of the heat medium returned from the terminal 4 to the heat pump type heat source device 2 gradually decreases, and accordingly, the temperature of the heat medium supplied to the heating terminal 4 also decreases (see the solid line after time t2).

At this time, since the heat medium at the target temperature of 50° C. is stored in the storage can body 19 of the hot water storage type combustion heat source device 3, the heat medium whose temperature has decreased from the target temperature when it flows out from the heat pump type heat source device 2. However, even if it flows into the hot water storage type combustion heat source device 3 and into the storage can body 19, the low temperature heat medium is mixed with the high temperature (50°C) heat medium in the storage can body 19 and the temperature is equalized, and the heating The temperature of the heat medium supplied to the terminal 4 (the temperature detected by the first heat medium temperature sensor 22) drops slightly, but before the high temperature (50°C) heat medium inside the storage can 19 completely drops. By stabilizing the heating output of the heat pump type heat source device 2, the degree of undershoot is small and the target temperature can be returned to the target temperature at an early stage (see the solid line after time t2).

Next, as a characteristic operation, during heating operation with only the heat pump type heat source device 2 in operation, the time chart of the above-mentioned Fig. 3 shows the time course of the temperature of the heat medium when the heat source device is switched. I will explain using In FIG. 3, a solid line indicates the change over time of the temperature of the heat medium supplied to the heating terminal 4 in the first embodiment (the temperature of the heat medium detected by the first heat medium temperature sensor 22), and the heating terminal in the comparative example 4 (temperature of the heating medium detected by the first heating medium temperature sensor 22) over time is shown by a dashed line. Note that the time t3 represents the time when heating operation is performed by operating only the heat pump type heat source device 2, and a stable state is reached after a certain period of time has passed.

From time t3 to t4, heating operation is performed by operating only the heat pump type heat source device 2, and the target temperature of the heat medium supplied to the heating terminal 4 is set to 50°C, and the heat pump type The compressor 5 and the like are controlled so that the temperature of the heat medium detected by the second heat medium temperature sensor 29 of the heat source device 2 reaches the target temperature. At this time, inside the circulation circuit 23 (second heat medium pipe 25, storage can body 19, third heat medium pipe 26) from the outlet of the liquid refrigerant heat exchanger 7 of the heat pump type heat source device 2 to the inlet of the heating terminal 4. The temperature of the heating medium is approximately the same as the target temperature (50° C.).

In the comparative example, if the operation is switched from the heat pump type heat source device 2 to the hot water storage type combustion heat source device 3 without overlapping operation at time t4 due to fluctuations in outside air temperature, etc., from time t4 onwards, from the heating terminal 4 to the hot water storage type The temperature of the heat medium returned to the combustion heat source device 3 gradually decreases, and accordingly, the temperature of the heat medium supplied to the heating terminal 4 also decreases (see the dashed line after time t4).

At this time, since the heat medium at the target temperature of 50° C. is stored in the storage can body 19 of the hot water storage type combustion heat source device 3, the heat medium whose temperature has decreased from the target temperature when it flows out from the heat pump type heat source device 2. However, even if it flows into the hot water storage type combustion heat source device 3 and into the storage can body 19, the low temperature heat medium is mixed with the high temperature (50°C) heat medium in the storage can body 19 and the temperature is equalized. Since the hot water storage type combustion heat source device 3 starts combustion after preheating the vaporizer 35 that vaporizes the fuel for a certain period of time, the heat source that heats the heat medium is used until the hot water storage type combustion heat source device 3 starts combustion. The temperature of the heating medium supplied to the heating terminal 4 (the temperature detected by the first heating medium temperature sensor 22) is such that the high temperature (50°C) of the heating medium inside the storage can body 19 has completely decreased. It is not possible to start combustion before the temperature rises, the degree of undershoot is large, and it takes time to return to the target temperature (see the dot-dashed line from time t4 to t5).

However, in the first embodiment, when switching from the heat pump type heat source device 2 to the hot water storage type combustion heat source device 3 at time t4 due to fluctuations in outside air temperature, etc., the hot water storage type combustion heat source device 3 starts operating and is not in operation. By not stopping the heat pump type heat source device 2 immediately, but by overlapping the operations of the hot water storage type combustion heat source device 3 and the heat pump type heat source device 2 for a certain period of time and then stopping the operation, the hot water storage type combustion heat source device 3 can use fuel. After preheating the vaporizer 35 for a certain period of time and before starting combustion, the heat pump type heat source device 2 heats the heat medium, so the temperature of the heat medium supplied to the heating terminal 4 (the first heat medium The temperature detected by the temperature sensor 22) does not completely drop the temperature of the high temperature (50°C) heat medium in the storage can 19, does not undershoot, and does not deviate significantly from the target temperature (temperature detected by the temperature sensor 22). (See solid line after t5).

At this time, when the hot water storage type combustion heat source device 3 is stopped and the heat pump type heat source device 2 is started from the state in which only the hot water storage type combustion heat source device 3 is operated, the time required to overlap the operation of the heat source device is (1 of t2). ), and when the heat pump heat source device 2 is stopped and the hot water storage combustion heat source device 3 is started from a state in which only the heat pump type heat source device 2 is operating, the time period for overlapping the operations of the heat source devices between t4 and t5 is ( 2). The relationship between the times in which the operations of the heat source devices overlap is controlled by setting the relationship (1) and (2) as 0≦(1)<(2). As a result, the heating medium returned from the heating terminal 4 to the heat pump type heat source device 2 can be heated for the necessary time, and efficient heating operation can be performed without overheating.

Next, in the second embodiment, the time course of FIG. 4 will be explained regarding the time course of the temperature of the heat medium when switching to the heat pump type heat source device 2 during heating operation with only the hot water storage type combustion heat source device 3 in operation. This will be explained using a chart. In FIG. 4, a solid line shows the temporal change in the temperature of the heat medium supplied to the heating terminal 4 (the temperature of the heat medium detected by the first heat medium temperature sensor 22) in the second embodiment. Note that the time t6 represents the time when heating operation is performed by operating only the hot water storage type combustion heat source device 3, and a stable state is reached after a certain period of time has passed.

From time t6 to t7, heating operation is performed by operating only the hot water storage type combustion heat source device 3, and the target temperature of the heat medium supplied to the heating terminal 4 is set at 50°C. The combustion of the evaporative burner 15 is performed so that the temperature of the heat medium detected by the first heat medium temperature sensor 22 of the type combustion heat source device 3 reaches the target temperature determined based on the set temperature set with the remote controller 32. The amount is controlled. At this time, the temperature of the heat medium in the circulation circuit 23 (storage can body 19, third heat medium pipe 26) from the storage can body 19 of the hot water storage type combustion heat source device 3 to the inlet of the heating terminal 4 is the target temperature ( 50°C).

In the comparative example, at time t7, if the operation is switched from the hot water storage type combustion heat source device 3 to the heat pump type heat source device 2 without overlapping due to fluctuations in outside air temperature, etc., from time t7 onwards, the hot water is transferred from the heating terminal 4 to the heat pump type heat source device 2. The temperature of the heat medium returned to the combustion heat source device 3 gradually decreases, and accordingly, the temperature of the heat medium supplied to the heating terminal 4 also decreases (see the dashed line after time t7).

On the other hand, in the second embodiment, at time t7, when the hot water storage type combustion heat source device 3 is switched to the heat pump type heat source device 2 due to a change in outside air temperature, etc., the heat pump type heat source device 2 starts operating. At the same time, the hot water storage type combustion heat source device 3 continues to operate without stopping, and by overlapping the operations of the heat source devices for a certain period of time, the hot water storage type The combustion heat source device 3 heats the heat medium. This can also prevent the temperature of the heat medium returned from the heating terminal 4 to the heat pump type heat source device 2 from decreasing (see the solid line after time t7).

At this time, when stopping the hot water storage type combustion heat source device 3 and starting the operation of the heat pump type heat source device 2 from a state in which only the hot water storage type combustion heat source device 3 is operating, the heat source device operates for the period (3) between t7 and t8. When the heat pump type heat source device 2 is stopped and the hot water storage type combustion heat source device 3 is started from a state in which only the heat pump type heat source device 2 is operated, the heat source device is operated for the time (4) between t10 and t11. Overlap actions. Then, the relationship between times (3) and (4) during which the operations of the heat source devices overlap is controlled as 0≦(3)<(4). As a result, the heating medium returned from the heating terminal 4 to the heat pump type heat source device 2 can be heated for the necessary time, and efficient heating operation can be performed without overheating.

2 Heat pump type heat source device 3 Hot water storage type combustion heat source device 4 Heating terminal 15 Evaporation type burner 19 Storage can body 23 Circulation circuit

Claims (1)

heating terminal,
a circulation circuit that circulates a heat medium to the heating terminal;
a heat pump type heat source device that heats the heat medium circulating in the circulation circuit;
a hot water storage type combustion heat source device that heats the heat medium circulating in the circulation circuit ;
A control means for controlling the heat pump type heat source device and the hot water storage type combustion heat source device ,
Heating operation is performed by the heating terminal using the heating medium,
The hot water storage type combustion heat source device includes a storage can that stores the heating medium therein, and a vaporization burner that heats the heating medium in the storage can,
The hot water storage type combustion heat source device is arranged downstream of the heat pump type heat source device with respect to the flow of the heat medium circulating in the circulation circuit,
The control means is configured to control a state in which only the hot water storage type combustion heat source device is operated, a case in which the hot water storage type combustion heat source device is stopped and the heat pump type heat source device starts operating, and a state in which only the heat pump type heat source device is operated. When the heat pump type heat source device is stopped and the hot water storage type combustion heat source device starts operating, separate times are provided for the operations of the heat pump type heat source device and the hot water storage type combustion heat source device to overlap, and when the hot water storage type It is better to start the heat pump type heat source device from a state where only the heat pump type heat source device is operated than to stop the hot water storage type combustion heat source device and start the operation of the heat pump type heat source device from a state where only the combustion heat source device is operated. A heating system characterized in that when the hot water storage type combustion heat source device is stopped and the hot water storage type combustion heat source device starts operating, the overlapping operation of the heat pump type heat source device and the hot water storage type combustion heat source device is controlled as a long time.

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