JP5212227B2 - Heat pump water heater - Google Patents

Description

  The present invention relates to a heat pump water heater using a heat pump as a heat source.

  Conventionally, in order to reduce the influence on the surroundings due to noise during operation, time zone grasping means for grasping that it is a specific time zone such as midnight, outside air temperature detecting means for detecting the outside air temperature, compressor operating state There has been proposed a heat pump hot water supply apparatus provided with a means for controlling.

  And the heat pump hot-water supply apparatus which stops the driving | operation in a specific time slot | zone at the time when hot water supply load is few with these control means is proposed (for example, refer patent document 1).

In patent document 1, the influence on the circumference by the noise at the time of a driving | operation can be reduced by stopping a driving | operation according to a hot water supply load.
Japanese Examined Patent Publication No. 7-65807

  However, in the conventional configuration, since the operation is stopped in the specific time zone, the specific time zone cannot be effectively used as the operation time for hot water storage, and during that time, no hot water is stored in the hot water storage tank, so the amount of stored hot water is reduced. When the hot water supply load is large, there is a problem that the hot water runs out and sufficient hot water supply cannot be performed.

  This invention solves the said conventional subject, and it aims at providing the heat pump hot-water supply apparatus which can reduce the influence on the circumference by the noise of an apparatus.

  In order to solve the above-described conventional problems, a heat pump water heater of the present invention includes a compressor that compresses a refrigerant, a heat exchanger for hot water that performs heat exchange between water and the refrigerant, an expansion valve that depressurizes the refrigerant, and the refrigerant that is in the atmosphere. Heat pump circuit in which the evaporator that absorbs the heat from the pipe is sequentially connected in an annular manner with refrigerant piping, the blower fan that blows air to the evaporator, the blower fan control means that controls the rotation speed of the blower fan, and the heat exchanger for hot water supply A hot water storage tank for storing the high temperature water, a hot water temperature detecting means for detecting the temperature of the hot water on the outlet side of the hot water heat exchanger, and an incoming temperature detecting means for detecting the temperature of the hot water on the inlet side of the hot water heat exchanger And a boiling pump that feeds from the lower part of the hot water storage tank to the hot water heat exchanger. During the boiling operation, the boiling pump is driven so that the temperature detected by the tapping temperature detection means becomes the target boiling temperature, and the incoming water temperature Inspection When the temperature detected by the means reaches a predetermined temperature or more, it is determined that boiling is not occurring, and the target boiling temperature is lowered, and the rotation speed of the blower fan is lowered as the target boiling temperature is lowered. When the target boiling temperature is lowered, the rotational speed of the blower fan is also reduced at the same time, so that noise can be reduced.

  The present invention can provide a heat pump hot water supply apparatus that can reduce the influence on the surroundings due to the noise of the apparatus.

The heat pump water heater of the first invention includes a compressor that compresses a refrigerant, a heat exchanger for hot water that exchanges heat between water and the refrigerant, an expansion valve that decompresses the refrigerant, and an evaporator that absorbs heat from the atmosphere. A heat pump circuit sequentially connected in an annular manner by refrigerant piping, a blower fan for blowing air to the evaporator, a blower fan control means for controlling the rotation speed of the blower fan, and a hot water storage tank for storing high-temperature water heated by a heat exchanger for hot water supply , A hot water temperature detecting means for detecting the temperature of hot water on the outlet side of the hot water supply heat exchanger, an incoming water temperature detecting means for detecting the temperature of hot water on the inlet side of the hot water heat exchanger, and for hot water supply from the lower part of the hot water storage tank A boiling pump for sending to the heat exchanger, and during boiling operation, the boiling pump is driven so that the temperature detected by the tapping temperature detecting means becomes the target boiling temperature, and the temperature detected by the incoming water temperature detecting means is predetermined. Warm When the target boiling temperature is lowered near the end of boiling, the target boiling temperature is decreased and the rotational speed of the blower fan is decreased as the target boiling temperature is decreased. At the same time, the rotational speed of the blower fan is reduced, so that noise can be reduced.

  In the heat pump hot water supply apparatus of the second invention, particularly in the first invention, the target boiling temperature can be set according to the actual use by changing the target boiling temperature according to the amount used up to the previous day. it can.

  The heat pump hot water supply apparatus of the third invention is provided with an outside air temperature detecting means for detecting the outside air temperature, particularly in the first or second invention, and the rotational speed of the blower fan is determined by the outside air temperature detected by the outside air temperature detecting means. By determining according to the incoming water temperature detected by the incoming water temperature detecting means, it is possible to set the optimum rotational speed of the blower fan by subdividing.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a configuration diagram of a heat pump hot water supply apparatus having a bath reheating function according to the present embodiment. In FIG. 1, the heat pump water heater of the present embodiment includes a tank unit 1 and a heat pump unit 2, and high-temperature water stored in a hot water storage tank 3 disposed in the tank unit 1 is supplied to the heat pump unit 2. Is generated.

  Next, the configuration of the heat pump unit 2 will be described. The heat pump unit 2 is configured by sequentially connecting a water-refrigerant heat exchanger 24, which is a heat exchanger for hot water supply, a compressor 25, an evaporator 26, and an expansion valve 27 in an annular manner through a refrigerant pipe. Since the high pressure side exceeds the critical pressure, the water flowing through the water / refrigerant heat exchanger 24 does not condense even if the temperature is lowered due to heat deprived, and the water refrigerant heat exchanger does not condense. It becomes easy to form a temperature difference between water and water, high-temperature hot water can be obtained, and heat exchange efficiency can be increased.

  In addition, since carbon dioxide, which is relatively inexpensive and stable, is used as the refrigerant, the product cost can be reduced and the reliability can be improved. In addition, carbon dioxide has an ozone depletion coefficient of zero and a global warming coefficient of about 1/700 of the alternative refrigerant HFC-407C, which is very small.

  Further, in the heat pump unit 2, the refrigerant is compressed by the compressor 25, the refrigerant discharged from the compressor 25 radiates heat by the water refrigerant heat exchanger 24, is decompressed by the expansion valve 27, and then is discharged from the air by the evaporator 26. The heat is absorbed and sucked into the compressor 25 again in a gas state. The compressor capacity control and the opening degree control of the expansion valve 27 are performed by setting the temperature of the discharge refrigerant detected by the temperature sensor 72 as discharge temperature detection means provided on the discharge side of the compressor 25 to a preset temperature. Controlled to maintain. Further, a pressure switch 73 is provided on the outlet side of the compressor 25 to stop the operation when a predetermined pressure or more is detected.

Furthermore, it is a blowing fan 74 that blows air to the evaporator 26, a temperature sensor 75 that is an outside air temperature detecting means that detects the outside air temperature, and an incoming water temperature detecting means that detects the temperature of hot water flowing into the water / refrigerant heat exchanger 24. There are provided a temperature sensor 76, a temperature sensor 77 that is a hot water temperature detecting means for detecting the temperature of hot water discharged from the water-refrigerant heat exchanger 24, and a control device 78 that is a blower fan control means for controlling the rotational speed of the blower fan. . The control device 78 includes a microcomputer and its peripheral circuits, and controls not only the blower fan control means for controlling the rotation speed of the blower fan, but also the control of each device in the heat pump unit 2 (for example, the target boiling temperature setting means). Also serves as expansion valve opening control means).

  Moreover, the hot water in the hot water storage tank 3 flows into the water-refrigerant heat exchanger 24 when the boiling pump 28 is operated, and exchanges heat with the refrigerant. A three-way valve 43 is provided between the outlet of the water-refrigerant heat exchanger 24 and the hot water storage tank 3 so that the hot water discharged from the water-refrigerant heat exchanger 24 is returned to the upper part or the lower part of the hot water storage tank 3. Has been switched.

  As a result, when the temperature of the hot water coming out of the water-refrigerant heat exchanger 24 is equal to or higher than a predetermined temperature, the three-way valve 43 is switched so as to return to the upper side of the hot water storage tank 3, and the hot water storage tank 3 passes through the upper boiling pipe 44. Returning to the top, hot water is stored in the upper part of the hot water storage tank 3 in a stacked state. When the temperature of the hot water coming out of the water-refrigerant heat exchanger 24 is lower than a predetermined temperature, the three-way valve 43 is switched so as to return to the lower side of the hot water storage tank 3, and the lower part of the hot water storage tank 3 is passed through the lower heating pipe 45. Return to.

  Next, the configuration of the tank unit 1 will be described. As described above, the tank unit 1 has the hot water storage tank 3, and a water supply pipe 31 for supplying low temperature water from a water supply source is connected to the bottom of the hot water storage tank 3, so that the water supply pressure is constantly in the tank. It is in a hanging state. In addition, a hot water discharge pipe 32 for discharging hot water in the hot water storage tank 3 is connected to an upper portion of the hot water storage tank 3 so that high temperature water can be supplied to a hot water supply terminal and a bathtub.

  Further, temperature sensors 46a to 46e, which are a plurality of remaining hot water temperature detecting means for detecting how much hot water remains, are provided above and below the hot water storage tank 3 to detect the temperature of the hot water in the hot water storage tank 3. Yes. In the present embodiment, the remaining hot water temperature detecting means is provided in the upper and lower five, but the number of remaining hot water temperature detecting means is not limited to this, and there may be no problem even if there are four or three, for example. .

  Next, a hot water supply circuit for supplying hot water to the hot water supply terminal will be described.

  The hot water supply circuit in the present embodiment is configured such that hot water having a desired temperature can be generated by connecting the terminal water supply pipe 33 branched from the water supply pipe 31 and the hot water discharge pipe 32 with the electric mixing valve 4. The mixing ratio of the electric mixing valve 4 is changed so that the temperature detected by the temperature sensor 41 provided on the downstream side of the electric mixing valve 4 becomes the temperature set by the remote control device provided in the kitchen or bathroom. Is done. Then, the hot water mixed at a desired temperature is supplied to the hot water supply terminal 42. Further, a flow rate sensor 55 that detects the amount of hot water supplied to the hot water supply terminal 42 is provided.

  Next, a hot water filling circuit and a reheating circuit for the bathtub 5 will be described.

  In the present embodiment, the hot water in the bathtub 5 and the high-temperature water in the hot water storage tank 3 exchange heat with the heat exchanger 6 and have a reheating function for reheating the hot water in the bathtub. . Therefore, the high-temperature water in the hot water storage tank 3 is supplied to the high-temperature circuit (reheating primary circuit) of the reheating heat exchanger 6 via the reheating hot water supply pipe 47 branched from the hot water discharge pipe 3. The hot water after the heat exchange is configured to return to the lower portion of the hot water storage tank 3 through the reheating hot water pipe 48. At this time, the reheating hot water pipe 48 is connected to the lower boiling piping 45 through the check valve 49 and is returned to the lower part of the hot water storage tank 3.

  Further, the low temperature side circuit (reheating secondary circuit) of the reheating heat exchanger 6 is configured such that hot water in the bathtub 5 is supplied by driving the bath pump 65, and after heat exchange is performed. The bathtub water is returned to the bathtub 5 again.

  In the high temperature side circuit (reheating primary circuit), a temperature sensor 71 serving as high temperature side outlet temperature detecting means is disposed downstream of the reheating pump 7 and the reheating heat exchanger 6, and the reheating pump is provided. By driving 7, the high-temperature water in the hot water storage tank 3 is conveyed to the reheating heat exchanger 6.

  And the adapter 51 of the bathtub 5 and the tank unit 1 are connected by the return connection pipe 61 and the forward connection pipe 62 in the connection parts 60a-60d. The return connection pipe 61 and the forward connection pipe 62 are connected to the reheating heat exchanger 6 by a return pipe 63 and a forward pipe 64, respectively. The bathtub 5, the return connection pipe 61, the return pipe 63, The reheating heat exchanger 6, the outgoing pipe 64, and the outgoing connecting pipe 62 are sequentially connected to constitute a reheating circuit.

  The hot water filling circuit for supplying hot water from the hot water storage tank 3 to the bathtub 5 includes a bath hot water supply pipe 34 branched from the hot water supply pipe 32 and a bath water supply pipe 35 branched from the water supply pipe 31 to the electric mixing valve 8. And hot water having a desired temperature can be generated. The mixing ratio of the electric mixing valve 8 is changed so that the temperature detected by the temperature sensor 81 provided on the downstream side of the electric mixing valve 8 becomes the temperature set by the remote control device provided in the kitchen or bathroom. Is done. Then, the hot water mixed at a desired temperature is supplied to the bathtub 5.

  Moreover, the flow rate sensor 82 is provided in the hot water filling circuit, and the amount of hot water supplied to the bathtub 5 is measured. Further, a two-way electromagnetic valve 83 is provided, and at the start of hot water filling, the supply of hot water to the bathtub 5 is started simultaneously with opening of the electromagnetic valve 83. After the electromagnetic valve 83 is opened, hot water filling is performed from two directions of the return pipe 63 and the forward pipe 64 to the bathtub 5. In addition, a check means 84 is provided for preventing the backflow of sewage.

  The return pipe 63 includes a bath pump 65 that is a conveying means for circulating hot water in the bathtub 5, a water level sensor 66 that detects the water level in the bathtub 5, and a bath temperature that detects the temperature of hot water in the bathtub 5. A temperature sensor 67 as a detection means is provided, and when the bath pump 65 is driven, hot water in the bathtub 5 is sucked into the return pipe 63 and flows into the forward pipe 64 via the reheating heat exchanger 6. It is returned to the bathtub 5 again.

  In addition, a flow switch 68 is provided between the bath pump 65 and the reheating heat exchanger 6 as hot water detection means for detecting whether there is hot water in the bathtub 5. Can be detected. That is, it is determined that there is hot water in the bathtub 5 when the flow switch 68 is turned on, and it is determined that there is no hot water in the bathtub 5 when the flow switch 68 is turned off.

  In addition, a remote control device 9 is installed in the bathroom, which is an operation means capable of operating the heat pump hot water supply device, and is a temperature setting means for setting the temperature of the hot water in the bathtub 5. , Set the temperature of hot water and water, fill the bath, and perform trial operation after installation work. The remote control device 9 has a display unit 91 for displaying information and an operation unit 92 for performing operations.

In FIG. 1, the heat pump hot water supply apparatus of the present embodiment also includes a control device 94 that receives an instruction from the remote control device 9 and commands each control device. The control device 94 is composed of a microcomputer and its electronic control parts, and sends commands to the devices (such as the bath pump 65 and the reheating pump 7) that constitute the tank unit 1.

  Furthermore, the remote control device 9 of the present invention is provided with a human body detection means 93 so that it can detect that a person has entered the bathroom. The human body detecting means 93 can be various sensors such as an infrared sensor, an illuminance sensor that detects the illuminance in the bathroom, and an impact (vibration) sensor that detects the vibration of the occupant and the opening and closing of the door. Is not specified.

  Furthermore, a temperature sensor 69 that is a reheating hot water temperature detecting means for detecting the temperature of the bath water heated by the reheating heat exchanger 6 is provided. This temperature sensor 69 detects the temperature of the hot water sent to the bathtub 5, and the reheating pump 7 is controlled so that the temperature detected by the temperature sensor 69 does not exceed the upper limit temperature. This is because the temperature sensor 69 can detect the temperature of the hot water supplied directly to the bathtub 5, so that hot water having a temperature higher than the upper limit temperature is not supplied to the bathtub 5 to prevent the bather from being burned. can do.

  Further, during the boiling operation, a target boiling temperature is set. The target boiling temperature is determined from load information such as the outside air temperature. FIG. 2 is a block diagram for determining the target boiling temperature. As shown in FIG. 2, in the present embodiment, the target boiling temperature is set according to each of the outside air temperature, the incoming water temperature, the outgoing hot water temperature, and the remaining hot water temperature (temperature detected by the temperature sensors 46a to 46e). The temperature is determined.

  Further, the target boiling temperature may be determined by learning control or the like. The learning control is control for determining the amount of hot water to be heated in the hot water storage tank 3 according to the actual use up to the previous day. In the present embodiment, the flow sensor 55 and the flow sensor 82 are provided. 42 and the amount of hot water supplied to the bathtub 5 are detected. And the amount of hot water used in one day is totaled over a plurality of days, the amount of hot water to be boiled on the next day is set based on the results, and the boiling temperature corresponding to the amount of hot water to be boiled is set as the target boiling temperature. By performing learning control in this way, it is possible to perform a boiling operation based on the usage record of the user, and therefore it is possible to perform a very energy-saving operation without increasing the amount of remaining hot water.

  On the other hand, the operation frequency of the compressor 25 is determined from the outside air temperature and the incoming water temperature, and the rotation speed of the blower fan is determined by the blower fan control means according to the operation frequency of the compressor 25. In the present embodiment, the operating frequency of the compressor 25 is associated with the rotational speed of the blower fan. As a result, if the operating frequency of the compressor 25 is determined, the rotational speed of the blower fan is also uniquely determined.

  In the capacity control of the compressor 25 and the opening degree control of the expansion valve 27, the temperature of the discharge refrigerant detected by the temperature sensor 72 as discharge temperature detection means provided on the discharge side of the compressor 25 is set in advance. The boiling pump 28 is driven to perform the boiling operation so that the temperature detected by the temperature sensor 77 becomes the set target boiling temperature.

  Then, when the end of the boiling operation is approaching, it is determined that the temperature detected by the temperature sensor 76 is close to the boiling level by detecting the predetermined temperature, and the target boiling temperature is set to the predetermined temperature for high pressure protection of the heat pump cycle. Reduce. As a result, the target boiling temperature is lowered and the temperature detected by the temperature sensor 76 is raised to some extent, so that the heat exchanging ability in the evaporator 26 can be reduced as the ability of the heat pump cycle. For this reason, the rotational speed of the blower fan is also reduced in accordance with a decrease in the target boiling temperature by a predetermined temperature during boiling. For this reason, noise can be reduced compared to when the fan is operated at a constant rotation speed.

(Embodiment 2)
The configuration of the heat pump hot water supply apparatus in the second embodiment is the same as that in the first embodiment. FIG. 3 is a diagram showing a table for determining the rotational speed of the blower fan according to the incoming water temperature and the outside air temperature. The difference between the second embodiment and the first embodiment is a flow for determining the rotational speed of the blower fan.

  In the first embodiment, the rotational speed of the blower fan is determined in association with the operating frequency of the compressor 25. However, in the second embodiment, the rotational speed of the blower fan is determined by a matrix of the incoming water temperature and the outside air temperature. A table is prepared in advance, and the rotational speed of the blower fan is determined according to the table.

  This makes it possible to determine the rotational speed of the blower fan in accordance with the table shown in FIG. 3 even when the incoming water temperature becomes high during the boiling operation, and can be set in great detail. As a result, the rotation speed of the blower fan can be controlled more efficiently, and when the capacity is not required, the rotation speed of the blower fan can be reduced to prevent noise.

  As described above, the heat pump hot water supply apparatus according to the present invention includes an integrated heat pump type hot water heater in which a heat pump cycle and a hot water supply cycle are integrally configured, a separate heat pump type hot water heater configured separately, and a heat exchanger for hot water supply. It can be applied to various heat pump water heaters such as a direct hot water heat pump type hot water heater that can discharge hot water heated in the same way.

The block diagram of the heat pump hot-water supply apparatus in Embodiment 1 of this invention Block diagram of target boiling temperature determination in Embodiment 1 of the present invention Table of rotation speed of blower fan in Embodiment 2 of the present invention

DESCRIPTION OF SYMBOLS 1 Tank unit 2 Heat pump unit 3 Hot water storage tank 5 Bathtub 6 Reheating heat exchanger 7 Reheating pump 9 Remote control device 28 Boiling pump 46a-e Temperature sensor (remaining hot water temperature detection means)
76 Temperature sensor (Incoming water temperature detection means)
77 Temperature sensor (Tapping temperature detection means)

Claims (3)

A heat pump circuit in which a compressor that compresses refrigerant, a heat exchanger for hot water supply that exchanges heat between water and the refrigerant, an expansion valve that depressurizes the refrigerant, and an evaporator that absorbs heat from the atmosphere in a cyclic manner are connected in an annular manner through a refrigerant pipe A blower fan that blows air to the evaporator, a blower fan control means that controls the rotation speed of the blower fan, a hot water storage tank that stores high-temperature water heated by the heat exchanger for hot water supply, and the heat exchanger for hot water supply The hot water temperature detecting means for detecting the temperature of the hot water on the outlet side of the hot water, the incoming temperature detecting means for detecting the temperature of the hot water on the inlet side of the heat exchanger for hot water supply, and the heat exchanger for hot water supply from the lower part of the hot water storage tank The boiling pump is driven so that the temperature detected by the tapping temperature detecting means during the boiling operation becomes the target boiling temperature, and the temperature detected by the incoming water temperature detecting means is Place Determined to be Flip Mai boiling and it becomes equal to or higher than the temperature, with lower the target boiling temperature, the heat pump water heater, characterized in that to reduce the rotational speed of the blowing fan with decreasing target boiling temperature. The heat pump hot-water supply apparatus according to claim 1, wherein the target boiling temperature is changed according to the amount of use up to the previous day. An outside air temperature detecting means for detecting an outside air temperature is provided, and the rotation speed of the blower fan is determined according to the outside air temperature detected by the outside air temperature detecting means and the incoming water temperature detected by the incoming water temperature detecting means. The hot water storage type water heater according to claim 1 or 2, wherein the hot water storage type water heater is provided.