JP2011002214A - Heat pump type hot water supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat pump type hot water supply device of high safety even in using a flammable refrigerant by reducing probability of leakage by efficiently sealing the refrigerant.SOLUTION: This heat pump type hot water supply device 1 includes a compressor 5, a condenser 6, an expansion valve 7 and an evaporator 8, and includes an annular circuit formed by connecting them by piping. A heat medium is sealed in the circuit, and its phase changes in the circuit. The heat medium passing through the condenser 6 is directly or indirectly cooled by the water for hot water supply, and when the heat medium is sealed, the heat medium passing through the condenser 6 is directly or indirectly cooled by the water for hot water supply, while operating the compressor 5.

Description

  The present invention relates to a heat pump type hot water supply apparatus.

  Conventionally, refrigerators, air conditioners, hot water heaters, etc. have mainly used chlorofluorocarbon refrigerants as the heat medium, but since the Montreal Protocol on Ozone-Depleting Substances was adopted in 1987, the ozone depletion coefficient has been increased. High chlorofluorocarbon refrigerants are regulated, and there is a shift toward using natural refrigerants that have zero ozone depletion coefficient and low global warming coefficient.

By the way, natural refrigerants include chemical substances such as ammonia, hydrocarbons such as isobutane, propane, and propylene, and CO _{2 that} exists in the natural world. Generally, among these natural refrigerants, a CO ₂ refrigerant is considered to have the highest safety, and has recently been adopted in a heat pump or the like as disclosed in Patent Document 1.

JP 2007-247985 A

However, since the CO ₂ refrigerant requires a high-pressure environment as compared with the environment in which the conventional chlorofluorocarbon refrigerant is used, there is a problem that a highly functional compressor is required and the manufacturing cost is greatly increased.

  On the other hand, the chemical substances and hydrocarbon-based refrigerants are refrigerants that are easily phase-changed in the same manner as fluorocarbon refrigerants, but these refrigerants are toxic and flammable, and are safe when leaked to the outside. There was concern.

  Then, this invention makes it a subject to provide a heat pump type hot water supply apparatus with high safety | security even if a combustible refrigerant | coolant is used by sealing a refrigerant | coolant efficiently and reducing the possibility of a leak.

  The invention according to claim 1 for solving the above-described problem is that the compressor, the condenser, the expansion means, and the evaporator are connected by a series of pipes to form an annular circuit. In a heat pump type hot water supply apparatus that forms a heat pump circuit in which a phase change heat medium is enclosed and exchanges heat generated by the condenser to supply hot water, the heat medium that passes through the condenser is directly or indirectly It is possible to seal the heat medium cooled by water for hot water supply and liquefied in the circuit, and when the heat medium is sealed, the heat medium passing through the condenser is directly operated while the compressor is operated. Alternatively, it is a heat pump type hot water supply device that is indirectly cooled with water for hot water supply.

The heat pump type hot water supply apparatus of the present invention directly transfers the heat medium passing through the condenser while operating the compressor when sealing the heat medium in a circuit including the compressor, the condenser, the expansion means, and the evaporator. It is supposed to be cooled with water for hot water supply either indirectly or indirectly. The term “directly” as used herein refers to cooling the heat medium of the heat pump circuit by passing hot water supply water to the secondary side of the condenser. On the other hand, “indirect” means that another heat medium passes through the secondary side of the condenser and cools the heat medium of the heat pump circuit, and the water for hot water supply cools the other heat medium. This is a case where the heat pump circuit is connected to a hot water supply circuit via an annular circuit having a heating terminal. Accordingly, since most of the heat medium in the condenser is liquefied, the heat medium in the liquefied state can be efficiently sealed.
Here, since the evaporator is generally an air / air heat exchanger, the surface area in contact with the outside air is widened and thinner than the thickness of the condenser member. On the other hand, the condenser is a gas / liquid heat exchanger that is designed to be strong enough to withstand the pressure applied by the compressor, so the member thickness is thicker than the evaporator and there is no seam. It is. That is, since the condenser has a higher pressure resistance than the evaporator, the possibility that the heat medium leaks to the outside can be reduced by sealing the heat medium with the condenser, for example. Therefore, even when a flammable hydrocarbon heat medium is employed, a highly safe heat pump hot water supply apparatus can be provided.

  According to the second aspect of the present invention, two or more temperature detection means are provided at a distance between the flow path before and after the condenser or the flow path in the condenser, and a difference in detection temperature of the temperature detection means is within a certain range. The heat pump hot water supply device according to claim 1, wherein the compressor is stopped on condition that it has become.

  The heat pump type hot water supply apparatus of the present invention is provided with a distance between the flow path before and after the condenser or the flow path in the condenser to provide two or more temperature detection means, and the difference in detection temperature of the temperature detection means is within a certain range. The compressor is stopped on the condition that it has become. Here, as described above, since the heat medium is cooled by the hot water supply water in the condenser, the temperature of the heat medium always decreases to a constant value before the heat medium is introduced into the condenser and discharged. . That is, for example, if the temperature detecting means is arranged on the outlet side and the inlet side of the condenser, it can be determined that the heat medium has been stored up to the inlet side when the detected temperature on the inlet side has decreased. Thereby, according to the heat pump type hot water supply device of the present invention, the heat medium liquefied at an appropriate timing can be sealed.

  The invention according to claim 3 is characterized in that the temperature detecting means is arranged in a secondary-side flow path that passes through the condenser and exchanges heat with the heat medium flowing through the heat pump circuit. 2. The heat pump type hot water supply apparatus according to 2.

In the heat pump type hot water supply apparatus of the present invention, the temperature detection means is arranged in the secondary side flow path that exchanges heat with the condenser. That is, as described above, the hot water flowing on the secondary side cools the heat medium of the heat pump circuit by the condenser. For example, if the temperature detection means is disposed in the flow path on the secondary side across the condenser, The detected temperature is low on the inlet side of the condenser and high on the outlet side. However, when the heat medium flowing through the heat pump circuit is substantially sealed, the detected temperature of hot water at the inlet side and the outlet side of the condenser hardly changes. In other words, when the temperature of the hot water on the secondary side stops changing, it can be said that almost all the heat medium on the heat pump circuit side is sealed. That is, the sealing state of the heat medium can be recognized without directly detecting the temperature change of the heat medium on the heat pump side.
Here, the flow path on the secondary side of the condenser does not need to change the phase of hot water flowing in the pipe line, and therefore has a lower pressure than a heat pump circuit in which a heat medium flows. Moreover, when the temperature detection means is provided in the flow path for hot water supply on the secondary side, even if hot water leaks due to incomplete mounting or poor sealing properties, safety is ensured because it is hot water. That is, by arranging the temperature detecting means in the secondary side pipe, it is possible to further reduce the possibility that the heat medium on the heat pump circuit side leaks to the outside. Thereby, even if a flammable hydrocarbon-based heat medium is used, a heat pump hot water supply apparatus with higher safety can be provided.

  According to a fourth aspect of the present invention, two or more stop valves are provided in a flow channel sandwiching the condenser or a flow channel in the condenser, and the first close valve located at a position far from the compressor on the piping path is closed first. The compressor is stopped and the second closing valve on the upstream side of the first closing valve is closed on the condition that the difference between the detected temperatures of the temperature detecting means is within a certain range. Item 4. The heat pump hot water supply device according to Item 2 or 3.

  Since the heat pump type hot water supply apparatus of the present invention is provided with the shut-off valve in the condenser or in the flow channel sandwiching the condenser, as described above, most of the heat medium can be stored in the condenser having excellent pressure resistance, thus leaking. Is less likely to do. In addition, when the heat medium is sealed, the first shut-off valve located far from the compressor on the piping path is closed first, and then the difference in temperature detected by the temperature detecting means is within a certain range. In addition, the second stop valve located upstream of the first close valve is closed and the compressor is stopped. That is, according to the present invention, by closing the second shut-off valve, the liquefied heat medium does not flow backward to the compressor side, and most of the heat medium can be reliably sealed in the condenser.

  According to a fifth aspect of the present invention, there is provided a time measuring means, and the compressor is stopped and upstream of the first closing valve on condition that a predetermined time has elapsed since the first closing valve was closed. The heat pump type hot water supply device according to claim 4, wherein the second closing valve on the side is closed.

  In the heat pump hot water supply apparatus of the present invention, time is measured on the condition that the first closing valve has been closed, and when the predetermined time has elapsed, the second closing valve is closed. That is, since it is possible to set a time based on data collected in advance through experiments or the like, the heat medium can be reliably sealed on condition that the set time has elapsed. Moreover, by using together with the above-described temperature detection means, even if a failure occurs in the temperature detection means, the time measurement means can cover it, so that the sealing operation can be reliably ended.

  According to the sixth aspect of the present invention, the compressor, the condenser, the expansion means, and the evaporator are connected by a series of pipes to form an annular circuit, and the heat medium that changes phase in the annular circuit is provided. A heat pump type hot water supply apparatus that is sealed to form a heat pump circuit and that exchanges heat generated by the condenser for use in hot water supply. The heat pump type hot water supply apparatus has time measuring means, and the condenser is a water-cooled heat exchanger. Water for hot water supply passes to the secondary side, and heat exchange is performed between the water for hot water supply on the secondary side and the heat medium, and when the heat medium is sealed, the compressor is operated while the heat medium is sealed. Water for hot water supply is passed through the secondary side of the condenser to cool the heat medium, and two or more shut-off valves are provided in the flow path sandwiching the condenser or the flow path in the condenser. A predetermined time has elapsed since the first shut-off valve in the far position was closed and the first shut-off valve was closed. As a condition, a heat pump type hot water supply apparatus characterized by closing the second shut-off valve upstream of the first shut-off valve to stop the compressor.

The heat pump type hot water supply apparatus of the present invention is configured to supply hot water to the secondary side of a condenser while operating the compressor when sealing a heat medium in a circuit including a compressor, a condenser, an expansion means, and an evaporator. It is supposed that the heat medium is cooled by passing the air. Thereby, since the liquefaction of the heat medium is promoted in the condenser, the liquefied heat medium can be efficiently sealed.
In addition, since the heat pump hot water supply apparatus of the present invention is provided with two or more shut-off valves in the flow path sandwiching the condenser or the flow path in the condenser, most of the liquefied heat medium is sealed in the condenser. It is possible to stop. Here, as described above, since the condenser has a higher pressure resistance than the evaporator, the possibility of the heat medium leaking outside is reduced by sealing the heat medium in the condenser. it can. Therefore, even when a flammable hydrocarbon heat medium is employed, a highly safe heat pump hot water supply apparatus can be provided.
Further, the heat pump type hot water supply apparatus of the present invention is provided with a time measuring means, and the time is measured on the condition that the first closing valve has been closed, and the second closing valve is closed when a predetermined time has elapsed. . That is, since it is possible to set a time based on data collected in advance through experiments or the like, the heat medium can be reliably sealed.

  The heat pump hot water supply apparatus of the present invention can cool the heat medium by passing hot water through the secondary side of the condenser while operating the compressor when sealing the heat medium. Therefore, it becomes possible to promote liquefaction of the heat medium, and the heat medium can be efficiently sealed. Further, since the liquefied heat medium can be sealed with a condenser, the possibility of leakage of the heat medium can be reduced. Thereby, safety can be ensured even if a flammable hydrocarbon-based heat medium is used.

It is a piping system diagram showing a heat pump type hot water supply apparatus according to an embodiment of the present invention. (A) of the condenser employ | adopted by embodiment of FIG. 1 is a perspective view, (b) is an expanded view of a coiled pipe line. It is explanatory drawing of the heat medium sealing operation | movement in a heat pump part, (a) is a normal operation state, (b) is an outlet side closing valve closed state, (c) is a compressor operation stop state. It is a time chart which shows operation | movement of each part of the heat pump type hot-water supply apparatus of embodiment of FIG. It is a flowchart which shows operation | movement of the heat pump type hot-water supply apparatus of embodiment of FIG. It is a flowchart which shows operation | movement of the heat pump type hot-water supply apparatus of another embodiment of this invention. It is a piping system diagram of the heat pump type hot water supply apparatus of another embodiment of the present invention. It is a flowchart which shows operation | movement of the hot water storage mode of the heat pump type hot-water supply apparatus of embodiment of this invention. It is a piping system diagram of a heat pump type hot water supply apparatus of still another embodiment of the present invention. It is an expanded view which shows the pipe line which has several stop valve and check valve before and behind a condenser. It is a piping system diagram of a heat pump type hot water supply apparatus in which a temperature sensor is arranged in a pipe line on the hot water storage unit side. It is a time chart which the temperature sensor of FIG. 11 shows. It is a perspective view which shows the modification of the pipe line which forms a condenser. It is a flowchart which shows operation | movement of the heat pump type hot-water supply apparatus of another embodiment of this invention. It is a flowchart which shows operation | movement of the heat pump type hot-water supply apparatus of another embodiment of this invention.

  Hereinafter, preferred embodiments for carrying out the present invention will be described with reference to the drawings.

  As shown in FIG. 1, the heat pump type hot water supply apparatus 1 is roughly composed of a heat pump unit 2 and a hot water storage unit 3, and is controlled by a control means (not shown).

  The heat pump unit 2 includes a compressor 5, a condenser (first heat exchanger) 6, an expansion valve (expansion means) 7, and an evaporator (second heat exchanger) 8 connected by a pipe, as in a known heat pump. In this circuit, a heat medium that changes phase is enclosed in the circuit. The heat medium is specifically a hydrocarbon-based refrigerant, and changes phase between a gas phase state and a liquid phase state according to pressure and temperature. The heat medium is combustible.

  The compressor 5 is a known hermetic compressor.

The condenser 6 has a coiled pipe line 10 as shown in FIG. That is, the condenser 6 is a water-cooled heat exchanger, and a coiled conduit 10 is provided in the outer portion 11. Then, the heat medium flows in the coiled conduit 10, and water passes through the outer portion 11. The coiled conduit 10 is composed of a homogeneous copper tube having a considerable thickness and has a pressure resistance of 16 MPa (gauge pressure) or more. That is, the coiled pipe line 10 has a design strength that can withstand a pressurization by the compressor 5 with a sufficient safety factor. Compared to another device constituting the heat pump unit 2 or a pipe connecting them. Excellent in pressure resistance. Therefore, even if the inside of a pipe | tube is made into a high voltage | pressure by the compressor 5, it is a structure which is hard to be damaged. Furthermore, since the coiled pipe line 10 has a coil shape, even if the inside of the pipe is at a high pressure, the entire pipe can be deformed to release the pressure. That is, the coiled pipeline 10 is superior in pressure resistance compared to a linear pipeline having the same design strength.
A shutoff valve 14 is provided in the middle of the coiled conduit 10. Specifically, the shut-off valve 14 is an intermediate shut-off valve 14 located at a substantially equal distance from both ends of the coiled conduit 10.

  Close valves 15 and 16 are provided at both ends of the coiled conduit 10 of the condenser 6. That is, one closing valve 15 is an outlet side closing valve (first closing valve) 15 provided on the outlet side of the coiled conduit 10, and the other is an inlet provided on the inlet side of the coiled conduit 10. This is a side stop valve (second stop valve) 16. Accordingly, since the closing valves 15 and 16 are arranged in the pipe line sandwiching the condenser 6 and the intermediate closing valve 14 is arranged in the coiled pipe line 10, the two closed regions 9a, 9b can be formed. That is, the heat medium can be sealed in the sealed regions 9a and 9b. In addition, the closing valves 14, 15, and 16 are known electromagnetic valves that are opened when energized.

  Further, temperature sensors 18 and 19 are provided in the vicinity of the inlet and the outlet of the coiled conduit 10, respectively. More specifically, an inlet side temperature sensor 18 is provided on the inlet side of the coiled conduit 10 that is the primary side of the condenser 6, and an outlet side temperature sensor 19 is provided on the outlet side of the coiled conduit 10. .

  The evaporator 8 is a gas-liquid heat exchanger, has a heat medium passage channel through which the heat medium passes, has fins (not shown) around it, and receives heat from the blower 24 to exchange heat.

As described above, the heat pump unit 2 includes the compressor 5, the condenser 6, the expansion valve 7, and the evaporator 8 that are annularly connected to each other. By operating the compressor 5, the internal gaseous heat The medium is compressed and enters the condenser 6. The heat medium is deprived of heat by the condenser 6 and liquefied. The liquefied heat medium is discharged from the expansion valve 7 and expands in volume in the evaporator 8 to take heat from the surroundings. Then, the heat medium is vaporized again and returns to the compressor 5.
The temperature on the inlet side and the temperature on the outlet side in the condenser 6 are measured by temperature sensors 18 and 19.

Next, the hot water storage unit 3 will be described. The hot water storage unit 3 includes a storage tank 20 and a hot water storage pump 32 and includes a circuit for storing hot hot water in the hot water storage unit 3.
The storage tank 20 is a tank that forms temperature stratification inside, and is a sealed tank. The storage tank 20 has an upper water inlet 22 and an upper water outlet 23 on the upper side, and a lower water inlet 25, a lower water outlet 26, and an auxiliary water inlet 27 on the lower side.

  The storage tank 20 is provided with a plurality of temperature sensors 30 with different heights. The temperature sensor 30 is provided in order to know where the hot water has accumulated.

In the present embodiment, the storage tank 20 and the secondary-side flow path 31 and the hot water storage pump 32 that exchange heat with the heat medium that passes through the condenser 6 and flows through the heat pump unit 2 are connected in a ring shape to form a hot water storage circuit 33. Is configured.
That is, the lower water outlet 26 of the storage tank 20 is connected to the water inlet side of the secondary side flow path 31 of the condenser 6 via the hot water storage pump 32, and the water outlet side of the secondary side flow path 31 of the condenser 6 is a three-way valve. It is connected to the upper side water inlet 22 of the storage tank 20 through 35.
The remaining port of the three-way valve 35 is connected to the auxiliary water inlet 27 of the storage tank 20.

  Accordingly, when the hot water storage pump 32 is started with the three-way valve 35 in communication with the hot water storage pump 32 and the upper water inlet 22, hot water is discharged from the lower portion of the storage tank 20, and the secondary flow path 31 of the condenser 6 is discharged. It passes and returns to the storage tank 20 from the upper side inlet 22 of the storage tank 20.

  On the other hand, when the hot water storage pump 32 is started with the three-way valve 35 in communication with the hot water storage pump 32 and the auxiliary water inlet 27, hot water is discharged from the lower part of the storage tank 20 and passes through the secondary flow path 31 of the condenser 6. And it returns to the storage tank 20 from the auxiliary water inlet 27 provided in the lower part of the storage tank 20.

Further, the remaining two openings of the storage tank 20, the upper water outlet 23 and the lower water inlet 25, are connected to an external pipe.
More specifically, the lower side water inlet 25 is connected to an external water source 36. On the other hand, the upper water outlet 23 is connected to an external hot water supply facility (for example, a hot water tap 38) via a hot water supply path 37. Further, a bypass water channel 40 is provided between the water source 36 and the hot water supply channel 37, and a flow rate control valve 41 is provided in the bypass water channel 40.

  Therefore, when the hot water tap 38 is opened, cold water enters the storage tank 20 from the lower water inlet 25 of the storage tank 20 due to the water pressure of the water source 36, and from the upper water outlet 23 provided at the upper part of the storage tank 20. Hot water is pushed out into the hot water supply passage 37. As will be described later, since hot water is stored on the upper side of the storage tank 20, when the hot-water tap 38 is opened, the hot water stored in the storage tank 20 due to the water pressure of the water source 36. However, hot water is pushed out into the hot water supply passage 37. Then, cold water flowing through the bypass water channel 40 is mixed with the hot water, the temperature is adjusted, and hot water is supplied from the hot water tap 38.

Next, the function of the heat pump type hot water supply apparatus 1 of this embodiment will be described.
The heat pump type hot water supply apparatus 1 of the present embodiment makes hot water by exchanging heat generated in the condenser 6 of the heat pump unit 2, stores the hot water in a storage tank 20, and supplies the hot water as needed. There is a storage mode in which hot water is stored in the storage tank 20 as an operation mode. When stopping the hot water storage, a heat medium sealing operation is performed in which the heat medium is sealed in the condenser 6 to store the heat medium.

  In the storage mode, the heat pump unit 2 is operated and the hot water storage pump 32 of the hot water storage unit 3 is activated. Further, in the storage mode, the three-way valve 35 is brought into a state where the hot water storage pump 32 and the upper side water inlet 22 communicate with each other.

  When the compressor 5 of the heat pump unit 2 is started, as described above, the internal gaseous heat medium is compressed and enters the coiled pipe line 10 that is the primary flow path of the condenser 6. Here, the gaseous heat medium that has entered the condenser 6 is adiabatically compressed by the compressor 5, and the temperature rises. At this time, the blower 24 rotates while being controlled by a control means (not shown).

  On the other hand, since the hot water storage pump 32 of the hot water storage unit 3 is activated, there is a water flow in the secondary side flow path 31 of the condenser 6, and the heat generated by the gaseous heat medium is deprived by the water flow in the secondary side flow path 31. As a result, the heat medium in the condenser 6 is liquefied.

  Further, the water flowing through the secondary side flow path 31 of the condenser 6 receives heat and raises the temperature. The hot water that has exited the secondary flow path 31 returns to the storage tank 20 from the upper-side water inlet 22 via the three-way valve 35.

  That is, cold water is taken out from the lower part of the storage tank 20, and the cold water is heated by the heat of the condenser 6 and introduced into the storage tank 20 from the upper side of the storage tank 20. As a result, hot water is accumulated on the upper side of the storage tank 20, and cold water remains on the lower side. And if the storage mode is continued, the ratio of the hot water in the storage tank 20 will increase gradually. Finally, hot water is filled in the storage tank 20.

Next, the heat medium sealing operation performed when stopping the storage will be described with reference to the drawings.
In the present embodiment, the heat medium sealing operation is performed when stopping the storage of hot water in the operation mode on a daily basis.
That is, when the compressor 5 is stopped when a predetermined condition is met from the state shown in FIG. 3A, the condenser is stopped before the compressor 5 is stopped according to the time chart of FIG. 4 and the flowchart shown in FIG. 6 closes the outlet side closing valve (first closing valve) 15 provided on the outlet side of the coiled pipe line 10 and reduces the rotational speed of the motor (not shown) of the compressor 5 and the blower 24 (the operating frequency). Change) (STEP 2 in FIG. 5).

On the other hand, the operation of the hot water storage pump 32 is maintained on the hot water storage section 3 side. However, the three-way valve 35 is switched so that the hot water storage pump 32 and the auxiliary water inlet 27 communicate with each other from the state where the hot water storage pump 32 and the upper water inlet 22 communicate with each other.
That is, as a result of switching the three-way valve 35, hot water is discharged from the lower part of the storage tank 20, passes directly through the secondary side flow path 31 of the condenser 6, and is an auxiliary water inlet provided at the lower part of the storage tank 20. 27 returns to the storage tank 20.

Prior to stopping the compressor 5, the outlet side closing valve (first closing valve) 15 provided on the outlet side of the coiled conduit 10 of the condenser 6 is closed. As a result, the pressure in the condenser 6 temporarily increases. As described above, the compressor 5 is slowed down, the operation of the hot water storage pump 32 is maintained (STEP 2), and the water flow through the secondary side flow path 31 of the condenser 6 is maintained. The heat medium in the vessel 6 is deprived of heat by the condenser 6 and liquefied. However, since the outlet side closing valve (first closing valve) 15 provided on the outlet side of the condenser 6 is closed as described above, the liquefied heat medium loses the outlet and accumulates in the condenser 6 ( FIG. 3 (b)).
Moreover, in STEP2, since the operation of the blower 24 is maintained, even if the heat medium leaks to the outside, the leaked gaseous heat medium can be diffused. That is, by temporarily maintaining the operation of the blower 24, it is possible to suppress an increase in the gas concentration at the leakage location, so that even if a flammable heat medium leaks, the safety is reduced. I won't let you. In this embodiment, the rotational speed of the blower 24 is controlled to a low speed. However, the present invention is not limited to this, and control to operate at the same rotational speed as the normal operation or a rotational speed higher than that may be performed. Absent.

  The gaseous heat medium sent from the compressor 5 to the condenser 6 is cooled by hot water flowing through the secondary-side flow path 31 of the condenser 6 to promote liquefaction, and accumulates in the condenser 6. Become. On the other hand, in other equipment, the heat medium is taken by the compressor 5 and the condenser 6 to be in a negative pressure state.

  Thus, when most of the heat medium in the circuit of the heat pump unit 2 enters the condenser 6 and is liquefied in the condenser 6, it is provided inside the condenser 6 as shown in FIG. The intermediate closing valve 14 and the inlet side closing valve (second closing valve) 16 of the condenser 6 are closed. As a result, most of the heat medium in the heat pump unit 2 is sealed and stored in a liquefied state in the sealed regions 9 a and 9 b in the condenser 6.

That is, in this embodiment, the two closed regions 9a and 9b are formed by using a total of three closing valves 14 to 16 including the outlet side closing valve 15, the inlet side closing valve 16, and the intermediate closing valve 14, and the heat medium is transferred to the heating medium. It is sealed with the sealing regions 9a and 9b including the inside of the condenser 6. At this time, since the hot water in the storage tank 20 flows to the secondary side of the condenser 6 and the heat medium is cooled, liquefaction of the heat medium is promoted and can be efficiently sealed. That is, according to this embodiment, the heat medium can be efficiently sealed by being dispersed in the two sealed regions 9a and 9b including the condenser 6 and the region up to the compressor 5 adjacent to the sealed region 9b. The possibility of medium leakage can be reduced. Furthermore, even if the heat medium leaks, a large amount of heat medium leaks unless all of the areas up to the compressor 5 adjacent to the sealed areas 9a and 9b and the sealed area 9b are damaged. There is no. Further, when the heat medium leaks to the outside, the fan 24 is kept in operation, so that the gaseous heat medium is diffused and an increase in concentration can be suppressed. That is, in the heat pump hot water supply apparatus 1 of the present embodiment, since the heat medium can be sealed in a plurality of regions, the possibility of the heat medium leaking is low, and even if it leaks, the heat medium leaks in large quantities. There is nothing. Furthermore, when a heat medium leaks, since the raise of the density | concentration of the heat medium of a leak location is suppressed by the air blower 24, safety | security is high.
Then, the compressor 5 is stopped.

  Here, the timing for closing the inlet side closing valve (second closing valve) 16 of the condenser 6 and the timing for stopping the compressor 5 are monitored for temperature variation in the condenser 6 according to the time chart of FIG. If this variation is within a certain range (STEP 3 in FIG. 5), the intermediate shut-off valve 14 and the inlet-side shut-off valve (second shut-off valve) 16 are closed (STEP 4 in FIG. 5). Stop. In the present embodiment, the intermediate closing valve 14 and the inlet side closing valve 16 are simultaneously closed. However, in the present invention, the intermediate closing valve 14 is first closed, and the inlet side closing is performed with a slight shift in timing. The structure which closes the valve 16 may be sufficient.

  That is, the condenser 6 introduces a high-temperature and high-pressure gas (heat medium) from the compressor 5, cools it, and discharges it to the expansion valve 7 side. The temperature of the introduction part is high and the temperature on the discharge side is low.

  However, as described above, when the outlet side of the condenser 6 is blocked by the outlet side closing valve (first closing valve) 15 and the heat medium in the heat pump unit 2 is successively sent to the condenser 6 to be cooled. Since the heat medium that has been liquefied and the temperature has decreased is accumulated, the low temperature region in the condenser 6 gradually increases.

  And finally, since almost all the heat medium in the condenser 6 is liquefied, the temperature variation in the condenser 6 is eliminated. Therefore, the temperature variation in the condenser 6 serves as an index for knowing the recovery rate of the heat medium into the condenser 6.

  Therefore, in the present embodiment, temperature sensors 18 and 19 are provided in the vicinity of the inlet and outlet of the coiled conduit 10 of the condenser 6 (flow paths before and after the condenser 6), and the temperature on the inlet side in the condenser 6 is determined. The temperature on the outlet side is monitored by temperature sensors 18 and 19. Then, the detected temperatures of the two temperature sensors 18 and 19 are compared, and the intermediate closing valve 14 and the inlet side closing valve (second closing valve) 16 are closed on condition that the difference between the two is small, and immediately thereafter. The compressor 5 is stopped.

  Specifically, when the temperature difference between the two becomes less than 5 to 1 degree Celsius, preferably less than 3 to 1 degree Celsius, the inlet side closing valve (second closing valve) 16 is closed, and immediately after that, the compressor 5 To stop. In the present embodiment, the compressor 5 is controlled from the normal operation to the low-speed operation, and it takes about 2 to 5 minutes for the compressor 5 to stop.

In addition to the temperature variation in the condenser 6, the intermediate closing valve 14 and the inlet side closing valve (second closing valve) 16 are closed according to the elapsed time after the outlet side closing valve (first closing valve) 15 is closed. Then, the compressor 5 may be stopped. For example, a timer (time measuring means) (not shown) that measures time is provided, and the outlet side closing valve (first closing valve) 15 is closed according to the flowchart shown in FIG. ) May be closed on condition that the intermediate closing valve 14 and the inlet side closing valve (second closing valve) 16 are closed, and the compressor 5 may be stopped. In place of the temperature variation condition in the condenser 6, the intermediate closing valve 14 and the inlet closing valve (second closing valve) are changed according to the elapsed time after the outlet closing valve (first closing valve) 15 is closed. 16 may be closed and the compressor 5 may be stopped.
The predetermined time described above is the time required for most of the heat medium in the heat pump unit 2 to enter the condenser 6 and be liquefied in the condenser 6, and the amount of heat medium in the heat pump unit 2 and the compressor This is a time determined by a compression capacity of 5. In practice, the time required for the heat medium to liquefy can be determined by experiment.

  On the other hand, when attention is paid to the operation on the hot water storage unit 3 side during the heat medium sealing operation, as described above, the three-way valve 35 is switched, and hot water is discharged from the lower water outlet 26 of the storage tank 20, and the condenser. 6 passes through the secondary side flow path 31 and returns to the storage tank 20 from the auxiliary water inlet 27 provided on the lower side of the storage tank 20. The reason for changing the return destination of the hot water to the storage tank 20 to the lower part of the storage tank 20 during the heat medium sealing operation is to prevent the temperature stratification in the storage tank 20 from being disturbed.

  Here, the characteristics of the storage tank 20 will be described. The storage tank 20 stores hot water in a state where temperature stratification is formed, and stores hot water at a high temperature on the upper side of the storage tank 20. The storage tank 20 utilizes the fact that high-temperature hot water has a lower specific gravity than low-temperature hot water, and if hot water is arranged on the upper side, convection does not occur in the storage tank 20 and is stratified according to temperature. In this state, hot water can be stored in the storage tank 20.

  In order to form temperature stratification in the storage tank 20, it is necessary to slowly introduce hot water having a temperature equal to or higher than a certain temperature into the storage tank 20 from the upper side inlet 22 of the storage tank 20. In short, in order for temperature stratification to be formed in the storage tank 20, it is necessary to introduce hot water having a temperature equal to or higher than a certain temperature from the upper water inlet 22 of the storage tank 20 to prevent convection in the storage tank 20. is there. In order for temperature stratification to be formed in the storage tank 20, hot water must be introduced slowly to prevent stirring in the storage tank 20.

  Conversely, when low-temperature hot water is introduced from the upper part of the storage tank 20, the introduced cold water tries to move to the lower part of the storage tank 20, causing convection and agitation, and hot hot water on the upper side and lower cold water enter. It becomes impossible to collect hot, hot water that is mixed and high in utility value.

  Returning to the description of the operation on the hot water storage unit 3 side during the heat medium sealing operation, the storage tank 20 employed in the present embodiment stores hot water in a state where the temperature stratification is formed as described above, and the upper side. The temperature of hot water stored in the water is high, and the temperature of hot water stored in the lower part is low. Even during the heat medium sealing operation, since hot water is discharged from the lower part of the storage tank 20 and introduced into the secondary side flow path 31 of the condenser 6, the secondary side flow path 31 of the condenser 6 Cold water is supplied, and the heat medium flowing through the coiled conduit 10 which is the primary side of the condenser 6 can be cooled and liquefied.

  However, as liquefaction progresses in the condenser 6, the amount of heat generated by the condenser 6 gradually decreases, so the temperature of the hot water discharged from the secondary side flow path 31 of the condenser 6 gradually decreases. . Here, in the present embodiment, as described above, the three-way valve 35 is switched, and the water that has passed through the secondary flow path 31 of the condenser 6 is the auxiliary water inlet 27 provided in the lower part of the storage tank 20. Therefore, even if the temperature of the hot water discharged from the secondary side flow path 31 of the condenser 6 is low, the temperature stratification in the storage tank 20 is not disturbed.

  In principle, the heat medium sealing operation is performed when the operation of the heat pump unit 2 is stopped, more specifically, when the compressor 5 is stopped. However, when the heat pump unit 2 is temporarily stopped and the compressor 5 is restarted within a short time, the heat medium sealing operation is not performed. For example, it is during intermittent operation such as defrosting operation.

  Alternatively, like the heat pump hot water supply apparatus shown in FIG. 7, a liquid / liquid heat exchanger 50 is provided in the flow path from the secondary side flow path 31 of the condenser 6 to the storage tank 20, and the liquid / liquid heat exchanger 50 is provided. When a circuit having a heating function such as heating by connecting a heating terminal 51 such as a floor heating appliance to the secondary side of the heater is used, the heat pump unit 2 is frequently operated according to the heat demand of the heating terminal 51. Intermittently. In such a case, since it is wasteful to perform the heat medium sealing operation one by one, the heat medium sealing operation is not performed even when the operation of the heat pump unit 2 is stopped.

  The same applies to the case where cooling is performed by using the cool air on the evaporator 8 side of the heat pump unit 2, and the operation of the heat pump unit 2 is frequently interrupted, so that even when the operation of the heat pump unit 2 is stopped. The heat medium sealing operation is not performed.

  In addition, the heat medium sealing operation is not performed even when the operation of the heat pump unit 2 must be stopped urgently due to an abnormality in the equipment.

On the contrary, when the operation of the heat pump unit 2 is stopped during normal use, the heat medium sealing operation is always performed. Therefore, in the storage tank 20, cold water sufficient to perform the heat medium sealing operation is left in the storage tank 20. It is necessary to keep.
In the present embodiment, the storage tank 20 is provided with a plurality of temperature sensors 30 with different heights, and it is possible to know to which position hot water has accumulated. Therefore, when the operation of the heat pump unit 2 is stopped, the stop operation must be executed at a stage where the temperature sensor 30a having the lowest height does not indicate a high temperature.

  When operating in the storage mode, when the second temperature sensor 30b from the bottom shows a high temperature, the operation moves to the heat medium sealing operation, and the heat pump unit 2 is stopped.

  That is, according to the flowchart of FIG. 8, while the storage mode is being executed, the storage amount of hot hot water in the storage tank 20 is constantly monitored. More specifically, the temperature of the second temperature sensor 30b from the bottom and the temperature of the lowest temperature sensor 30a are monitored, the temperature sensor 30b indicates a high temperature of 90 degrees Celsius or higher, and the temperature sensor 30a is less than this. If temperature is shown, it will transfer to heat medium sealing operation. That is, when the temperature of the second temperature sensor 30b from the bottom in the storage tank 20 indicates 90 degrees Celsius or higher and the temperature sensor 30a in the lowermost part indicates a temperature lower than this, a little chilled water remains in the storage tank 20. Thus, during the heat medium sealing operation, cold water can be supplied to the secondary side flow path 31 of the condenser 6, and the heat medium in the condenser 6 can be liquefied.

In the heat pump type hot water supply apparatus of the present embodiment, when the heat pump unit 2 is stopped, the heat medium is sealed in the sturdy condenser 6, so that the heat medium is damaged when the pipes are damaged or corroded. Even if it leaks, the amount of heat medium leaked decreases.
Even if the house is hit by a fire and the heat pump water heater is exposed to a high temperature, the heat medium is sealed in the sturdy condenser 6, so that the condenser 6 is not damaged and flammable heat is generated. Even if a medium is used, the fire is not intensified.

  Moreover, in the said embodiment, although the hot water of the storage tank 20 was passed to the secondary side of the condenser 6, the heat medium which flows into the primary side of the said condenser 6 was directly cooled with the hot water for hot water supply. 9, like the heat pump type hot water supply apparatus shown in FIG. 9, the secondary flow path of the condenser 6 flows through an annular circuit formed by connecting the liquid / liquid heat exchangers 50 and 52 and the circulation pump 53 with piping. The heat medium may be passed through the secondary side of the condenser 6 and the heat medium flowing to the primary side of the condenser 6 may be indirectly cooled with hot water for hot water supply. Specifically, the hot water storage circuit 33 is passed through the liquid / liquid heat exchanger 52, the heat medium passing through the secondary side of the condenser 6 is cooled by the liquid / liquid heat exchanger 52, and the cooled heat The heat medium on the primary side of the condenser 6 is cooled by the medium. That is, as a result, the heat medium passing through the primary side of the condenser 6 is indirectly cooled by the hot water flowing through the hot water storage circuit 33, and thus the same action as the heat pump hot water supply device 1 of the above-described embodiment. An effect can be obtained. In the embodiment shown in FIG. 9, a heating terminal 51 such as a floor heating appliance is connected to the secondary side of the liquid / liquid heat exchanger 50 as in FIG. 7.

  In the above embodiment, the configuration in which the shut-off valves 15 and 16 are arranged one by one before and after the condenser 6 is shown. However, the present invention is not limited to this, and two or more shut valves are provided before and after the condenser 6. You may be the structure which arranged the valve or the non-return valve. For example, as shown in FIG. 10, two outlet side stop valves 15 a and 15 b are arranged on the outlet side of the condenser 6, and two check valves 48 a and 48 b are arranged on the inlet side of the condenser 6. . With such a configuration, even if any of the shutoff valves 15 or the check valves 48 malfunctions, the heat medium is more reliably sealed by the other shutoff valves 15 and check valves 48. Therefore, a safer heat pump hot water supply apparatus can be provided.

  In the above embodiment, the configuration in which the two temperature sensors 18 and 19 are provided in the pipe line on the heat pump unit 2 side or the pipe line on the hot water storage unit 3 side is shown, but the present invention is not limited to this. Two or more temperature sensors may be provided in both or one of the heat pump unit and the hot water storage unit 3. Also in this case, it is preferable that a plurality of temperature sensors be arranged with a distance in the flow path before and after the condenser 6 or in the flow path in the condenser 6.

In the above embodiment, in order to stop the operation of the compressor 5 and end the heat medium sealing operation, the temperature sensors 18 and 19 are arranged on the primary side (heat pump unit 2 side) in the condenser 6, Although the configuration for monitoring the variation in the temperature of the medium is shown, the present invention is not limited to this configuration. For example, as shown in FIG. 11, a configuration may be adopted in which temperature sensors 18 and 19 are arranged on the secondary side (hot water storage unit 3 side) passing through the condenser 6 to monitor the temperature variation of the hot water. . Even in this case, the temperature sensors 18 and 19 are preferably arranged in the flow paths before and after the condenser 6.
Here, as described above, in the condenser 6, heat exchange is performed between the primary side heat medium and the secondary side hot water. Specifically, since the primary side heat medium is adiabatically compressed by the compressor 5, it is introduced into the condenser 6 in a high temperature state. On the other hand, hot water that is not heated in the storage tank 20 is introduced as the secondary hot water. That is, the heat medium on the primary side is cooled to the hot water on the secondary side in the condenser 6 and cooled to a constant temperature on the outlet side. That is, by passing through the condenser 6, the heat medium on the primary side is cooled, and the hot water on the secondary side is heated.
Therefore, in the above-described embodiment, in order to detect the state of the heat medium sealed in the pipe, the temperature of the heat medium on the outlet side and the inlet side of the condenser 6 is detected, The operation of the compressor 5 is stopped on condition that the difference from the temperature on the outlet side has reached a certain level or less.
However, it may be difficult to provide the temperature sensors 18 and 19 on the condenser 6 side in view of maintaining the pressure resistance in the pipe and sealing performance. Therefore, a configuration is conceivable in which the temperature sensors 18 and 19 are provided on the secondary side pipe line which can ensure safety even if the pipe line has a low pressure, and the temperature of the hot water is monitored. According to this configuration, immediately after the start of the heat medium sealing operation, as shown in FIG. 12, the temperature sensor 18 on the incoming side shows a low temperature, and the temperature sensor 19 on the outgoing side shows a high temperature. However, the outlet-side temperature sensor 19 approaches the temperature detected by the inlet-side temperature sensor 18 every time. This indicates that heat exchange between the primary side heat medium and the secondary side hot water is no longer performed. In other words, the heat medium is sufficiently sealed in the condenser 6. That is, in the present invention, the operation of the compressor 5 can be stopped at substantially the same timing even if the temperature sensors 18 and 19 are provided in the secondary hot water pipe.

  In the said embodiment, as shown in FIG.2 (b), although the structure which provided the shut-off valves 14-16 in the pipe line containing the coiled pipe line 10 in series was shown, this invention is limited to this structure. However, the intermediate shutoff valve 14 may not be employed, and the shutoff valves 15 and 16 may be arranged only before and after the condenser 6. That is, it is sufficient that most of the heat medium can be sealed in the condenser 6.

  In the above-described embodiment, the configuration in which the outlet side stop valve 15 or the inlet side stop valve 16 is arranged before and after the condenser 6 is shown, but the present invention is not limited to this configuration. That is, not only before and after the condenser 6, but also a configuration in which a stop valve is arranged in a pipe constituting the circuit of the heat pump unit 2. Even in this case, it is preferable to dispose a closing valve in a pipe between the compressor 5 and the expansion valve 7 in which the heat medium can exist in a liquid state.

  In the above embodiment, the configuration in which the coiled conduit 10 is adopted for the condenser 6 is shown. However, the present invention is not limited to this configuration. For example, as shown in FIG. A condenser having a pipe welded so that a pipe (heat pump part 2 side) and a secondary pipe (hot water storage part 3 side) are spirally formed in parallel, or a condenser having a plate-type laminated pipe line It does not matter.

  In the above embodiment, the operation of the blower 24 is temporarily maintained by the heat medium sealing operation, and the structure that can diffuse when the heat medium leaks is shown, but the present invention is not limited to this, The structure which does not maintain the driving | operation of the air blower 24 may be sufficient. However, considering the case where the heat medium leaks, it is preferable to temporarily maintain the operation of the blower 24 in the heat medium sealing operation.

  In the above embodiment, as shown in the flowcharts of FIGS. 5 and 6, after STEP 1 operation stop command, in STEP 2, the outlet side closing valve 15 of the condenser 6 is closed, the compressor 5 is operated at low speed, and the hot water storage pump 32. However, the present invention is not limited to this, and the low-speed operation of the compressor 5 and the operation maintenance of the hot water storage pump 32 are maintained as shown in the flowcharts of FIGS. After executing this control, the control for closing the outlet side closing valve 15 of the condenser 6 may be executed. According to this structure, the pressure rise in the condenser 6 in the case of heat medium sealing operation can be suppressed more.

DESCRIPTION OF SYMBOLS 1 Heat pump type hot water supply apparatus 2 Heat pump part 5 Compressor 6 Condenser 7 Expansion valve (expansion means)
8 Evaporator 10 Coiled line 15 Outlet side closing valve (first closing valve)
16 Inlet side shutoff valve (second shutoff valve)
18 Inlet temperature sensor (temperature detection means)
19 Outlet temperature sensor (temperature detection means)

Claims (6)

Each member of the compressor, the condenser, the expansion means, and the evaporator is connected by a series of pipes to form an annular circuit, and a heat medium that changes phase is enclosed in the annular circuit to constitute a heat pump circuit, In a heat pump type hot water supply apparatus for exchanging heat generated by the condenser for use in hot water supply,
The heat medium passing through the condenser is cooled directly or indirectly by hot water supply water, and the heat medium liquefied in the circuit can be sealed,
A heat pump type hot water supply apparatus that cools a heat medium passing through a condenser directly or indirectly with water for hot water supply while operating the compressor when sealing the heat medium.   Two or more temperature detection means are provided at a distance to the flow path before and after the condenser or the flow path in the condenser, and the compressor is provided on condition that the difference between the detection temperatures of the temperature detection means is within a certain range. The heat pump type hot water supply device according to claim 1, wherein the heat pump type hot water supply device is stopped.   The heat pump type hot water supply apparatus according to claim 2, wherein the temperature detection means is arranged in a secondary side flow path that exchanges heat with a heat medium flowing through a condenser and flowing through a heat pump circuit. Two or more shut-off valves are provided in the flow channel sandwiching the condenser or the flow channel in the condenser,
First, the first shut-off valve located far from the compressor on the piping path is closed,
The compressor is stopped on the condition that the difference between the detected temperatures of the temperature detecting means is within a certain range, and the second closing valve on the upstream side of the first closing valve is closed. The heat pump hot water supply apparatus according to 2 or 3. Having time measuring means,
The compressor is stopped and a second closing valve upstream of the first closing valve is closed on the condition that a predetermined time has passed since the first closing valve was closed. 4. A heat pump type hot water supply apparatus according to 4. Each member of the compressor, the condenser, the expansion means, and the evaporator is connected by a series of pipes to form an annular circuit, and a heat medium that changes phase is enclosed in the annular circuit to constitute a heat pump circuit, In a heat pump type hot water supply apparatus for exchanging heat generated by the condenser for use in hot water supply,
Having time measuring means,
The condenser is a water-cooled heat exchanger that passes hot water on the secondary side and exchanges heat between the hot water on the secondary side and the heat medium.
When sealing the heat medium, cooling the heat medium by passing water for hot water supply to the secondary side of the condenser while operating the compressor,
Two or more shut-off valves are provided in the flow channel sandwiching the condenser or the flow channel in the condenser,
First, the first shut-off valve located far from the compressor on the piping path is closed,
A heat pump system characterized in that the compressor is stopped and the second closing valve on the upstream side of the first closing valve is closed on the condition that a predetermined time has passed since the first closing valve was closed. Hot water supply device.

Images