JP5134446B2 - Heat pump type water heater - Google Patents

Description

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

  Conventionally, in this type of heat pump type hot water supply apparatus, as shown in Patent Document 1, a heat pump circuit in which a compressor, a water-refrigerant heat exchanger, a decompression unit, and an air heat exchanger are connected in sequence, and the air heat exchange. It is common to include a blower fan that circulates air to the vessel and a control means that controls these, and to determine the number of rotations of the blower fan according to the outside air temperature and perform an efficient operation.

In addition, as shown in Patent Document 2, in a general heat pump type hot water supply apparatus, as the target boiling temperature of hot water is higher, the heating capability is required, and therefore, the rotation speed of the blower fan is increased. It was.
JP 2002-89958 A JP 2004-309084 A

  However, in this conventional one, when the target boiling temperature is high, the refrigerant discharge temperature from the compressor also becomes high. Therefore, when the rotational speed of the blower fan is increased as in Patent Document 2, the refrigerant discharge pressure exceeds the upper limit pressure. There was a case. When the operation is continued in a state where the upper limit pressure is exceeded, there has been a problem that the durability of the compressor, other functional parts and piping is remarkably lowered.

  In addition, when the rotation speed of the blower fan is fixed so that the upper limit pressure is not exceeded over the entire range of the target boiling target temperature, if the target boiling temperature is low, the rotation of the blower fan is low even though the refrigerant discharge pressure is low. Since the number is low, there is a problem that the heating efficiency (COP) is lowered.

Therefore, in order to solve the above problems, the present invention provides a heat pump circuit in which a compressor, a water-refrigerant heat exchanger, a decompression means, and an air heat exchanger are sequentially connected, and a blower fan that circulates air to the air heat exchanger; , a hot water storage tank for hot water storage hot water, the hot water of the hot water storage tank the water - and heating circulation pump for circulating the refrigerant heat exchanger, the water - target for setting the temperature of the hot water water that raised boiling refrigerant heat exchanger Boiling temperature setting means, compressor control means for determining the operating frequency of the compressor or the target discharge temperature of the refrigerant according to the target boiling temperature, and the temperature of hot water boiled by the water-refrigerant heat exchanger the heat pump type hot water supply apparatus having but a heating control means for controlling the rotational speed of the heating circulation pump so that the target water heating temperature, and a fan controlling means for determining a target rotational speed of the blowing fan Oite, the blowing fan control means was set to the target water heating temperature is set higher low target rotation speed of the blower fan.

  In addition, an outside air temperature sensor for detecting the outside air temperature is provided, and the blower fan control means corrects the rotation speed of the blower fan to decrease as the outside air temperature increases.

  As described above, according to the present invention, the higher the target boiling temperature is, the lower the rotation speed of the blower fan is. Therefore, the upper limit pressure is not exceeded over the entire range of the target boiling temperature, and the heating fan has good heating efficiency. It was possible to operate at the number of revolutions, and high-efficiency operation was possible under operating conditions that ensured sufficient durability of the equipment.

Next, an embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, 1 is a hot water storage tank unit having a hot water storage tank 2 for storing hot water, 3 is a heat pump heating means for heating hot water in the hot water storage tank 2, and 4 is connected to the lower part of the hot water storage tank 2. A heating circulation circuit comprising a heating return pipe 5 and a heating return pipe 6 connected to the upper part of the hot water storage tank 2; 7 a water supply pipe connected to the lower part of the hot water storage tank 2 for supplying water to the hot water storage tank 2; A hot water discharge pipe connected to the upper part of the hot water storage tank 2 for discharging hot water stored in the hot water.

  9 is a water supply bypass pipe branched from the water supply pipe 7, 10 is a mixing valve that mixes hot water from the hot water discharge pipe 8 and water from the water supply bypass pipe 9 to make hot water at a hot water supply set temperature, and 11 is mixed by the mixing valve 10 A plurality of hot water supply temperature sensors 12 for detecting a hot water supply temperature later, a plurality of hot water storage temperature sensors 12 for detecting the temperature of hot water in the hot water storage tank 2, and a plurality of sensors 12 in the hot water storage tank unit 1. Is a hot water storage control means for controlling the operation of each device, and includes a target boiling temperature setting means 14 for setting a target boiling temperature Tset, which will be described later.

  The heat pump heating means 3 includes a compressor 15 that compresses refrigerant, a water-refrigerant heat exchanger 16 that exchanges heat between the high-temperature and high-pressure refrigerant and hot water in the hot water storage tank 2, and a water-refrigerant heat exchanger 16 passage. A heat pump cycle 19 in which an electronic expansion valve 17 as decompression means for decompressing the subsequent refrigerant and an air heat exchanger 18 as an evaporator for evaporating the low-temperature and low-pressure refrigerant from the electronic expansion valve 17 are connected in an annular shape by a refrigerant pipe. And a heating circulation pump 20 provided in the middle of the heating circulation circuit 4 on the water side of the water-refrigerant heat exchanger 16 for circulating hot water in the hot water storage tank 2. Here, the water-refrigerant heat exchanger 16 is a counter-flow heat exchanger in which the flow direction of the refrigerant and the flow direction of the water to be heated are opposed to each other. The air heat exchanger 18 includes the air heat exchanger 18. A blower fan 21 for adjusting the evaporation capacity by adjusting the amount of air to be circulated is provided.

  A refrigerant discharge temperature sensor 22 is provided between the compressor 15 and the water-refrigerant heat exchanger 16 to detect the refrigerant discharge temperature, and 23 is provided between the water-refrigerant heat exchanger 16 and the electronic expansion valve 17. An outflow temperature sensor that detects the outflow temperature of the refrigerant from the water-refrigerant heat exchanger 16, 24 is provided on the air inlet side of the air heat exchanger 18, and is an outside air temperature sensor that detects the outside air temperature, and 25 is water. A water temperature sensor for detecting the water temperature on the water side of the refrigerant heat exchanger 16, and a water temperature sensor 26 for detecting the water temperature on the water side of the water-refrigerant heat exchanger 16.

  27 is a heating control means for receiving the output of each sensor in the heat pump type heating means 3 and controlling the operation of each device. The heating control means 27 is communicably connected to the hot water storage control means 13 and operates in cooperation with the hot water storage control means 13. Furthermore, the compressor control means 28 which sets the operating frequency of the compressor 16 mentioned later and the ventilation fan control means 29 which sets the target rotation speed N of the ventilation fan 21 mentioned later are provided.

Next, the operation of this embodiment will be described.
When hot water is supplied, when a user opens a faucet (not shown), city water flows from the water supply pipe 7 at the bottom of the hot water tank 2 and is boiled from the upper part of the hot water tank 2 and stored in the midnight hours. The hot water that is present is poured into the tap pipe 8. Then, hot water from the hot water discharge pipe 8 and city water from the feed water bypass pipe 9 are mixed by the mixing valve 10. At this time, the mixing ratio of the mixing valve 10 is adjusted so that the hot water temperature after mixing detected by the hot water temperature sensor 11 becomes the hot water set temperature set by a remote controller (not shown) or the like. Hot water is supplied from the faucet.

  In the midnight time zone, the hot water storage control means 13 instructs the heating control means 27 to start a boiling operation so as to start the boiling operation so that the hot water in the hot water storage tank 2 reaches a predetermined target boiling temperature Tset. Then, the compressor control means 28 of the heating control means 27 sets the operation frequency of the compressor 15 according to the outside air temperature Ta detected by the outside air temperature sensor 24 to control the compressor 15 and also sets the target boiling temperature Tset +. The target discharge temperature TD is set by finely adjusting the constant value according to the level of the outside air temperature Ta, and the electronic expansion valve 17 is set so that the refrigerant discharge temperature detected by the refrigerant discharge temperature sensor 22 becomes the target discharge temperature TD. To control the opening degree. At the same time, the heating control means 27 controls the rotation speed of the heating circulation pump 20 so that the hot water heated by the water-refrigerant heat exchanger 16 detected by the boiling temperature sensor 26 becomes the target boiling temperature Tset.

  The blower fan control means 29 of the heating control means 27 decreases the target rotational speed N of the blower fan 21 as the target boiling temperature Tset is higher, and sets the target rotational speed N of the blower fan 21 as the target boiling temperature Tset is lower. While setting it high, it correct | amends so that the target rotation speed N of the ventilation fan 21 determined according to the target boiling temperature Tset may become low, so that the outside temperature Ta detected by the outside temperature sensor 24 becomes high. Here, the blower fan control means 29 may store table data as shown in FIG. 2 in advance, and may set the target rotational speed N of the blower fan 21 based on this table data.

  Here, the predetermined target boiling temperature Tset can secure a predicted amount of hot water supply for the next day based on the actual hot water supply such as the maximum value and average value of the past hot water supply accumulated and stored in the hot water storage control means 13. Thus, it is calculated by the target boiling temperature setting means 14 and is determined in the range of 65 ° C. to 90 ° C.

  Then, as the boiling operation proceeds, the water in the lower part of the hot water storage tank 2 is circulated to the heat pump type heating means 3, and the hot water heated from the upper part of the hot water storage tank 2 to the target boiling temperature Tset is stored in a stacked state. Is done. The hot water storage temperature sensor 12 detects that the required amount of hot water has been boiled in the hot water storage tank 2 or the incoming water temperature Twi detected by the incoming water temperature sensor 25 of the heat pump heating means 3 is higher than a predetermined high temperature that is difficult to boil up. Or the hot water storage control means 13 issues a stop instruction to the heating control means 27 to stop the boiling operation, and the heating control means 27 The operation of the heating circulation pump 20 is stopped and the boiling operation is finished.

  Thus, since the target rotation speed N of the blower fan 21 is lowered as the target boiling temperature Tset is higher, the upper limit pressure is not exceeded over the entire range of the target boiling temperature Tset, and the heating fan 21 has good heating efficiency. It was possible to operate at the number of revolutions, and it became possible to operate with high efficiency under the operating conditions that ensured sufficient durability of the equipment.

  In addition, since the correction is performed so that the rotational speed of the blower fan 21 is decreased as the outside air temperature Ta is higher, highly efficient control adapted to the external environment can be performed.

  Note that the present invention is not limited to the above-described embodiment, and can be changed without changing the gist thereof. For example, the compressor control means 28 is a refrigerant according to the target boiling temperature Tset. The target discharge temperature TD is set, but the operation frequency of the compressor 16 corresponding to the target boiling temperature Tset may be set.

  Further, the hot water storage tank unit 1 and the heat pump heating means 3 are divided into separate housings, but may be integrated, and in that case, the hot water storage control means 13 and the heating control means 27 are also integrated control means. It is good.

The system diagram of the heat pump type hot water supply apparatus of one Embodiment of this invention. The data table of the ventilation fan target rotation speed of the same embodiment.

Explanation of symbols

14 Target boiling temperature setting means 15 Compressor 16 Water-refrigerant heat exchanger 17 Electronic expansion valve (pressure reduction means)
18 Air heat exchanger 19 Heat pump cycle 21 Blower fan 24 Outside air temperature sensor 28 Compressor control means 29 Blower fan control means

Claims (2)

A heat pump circuit in which a compressor, a water-refrigerant heat exchanger, a decompression unit, and an air heat exchanger are sequentially connected; a blower fan for circulating air to the air heat exchanger; a hot water storage tank for storing hot water; and the hot water storage tank hot water the water - and heating circulation pump for circulating the refrigerant heat exchanger, the water - and the target water heating temperature setting means for setting the temperature of the hot water water that raised boiling refrigerant heat exchanger, the target water heating temperature Compressor control means for determining the operating frequency of the compressor or the target discharge temperature of the refrigerant according to the above, and heating circulation so that the temperature of the hot water boiled by the water-refrigerant heat exchanger becomes the target boiling temperature and heating control means for controlling the rotational speed of the pump, the heat pump type hot water supply device provided with a blowing fan control means for determining a target rotational speed of the blower fan, the blower fan control means, the The heat pump type hot water supply apparatus characterized by higher standard boiling temperature is higher and so as to set a lower target rotation speed of the blower fan. The heat pump hot water supply according to claim 1, wherein an outside air temperature sensor for detecting an outside air temperature is provided, and the blower fan control means corrects the rotation speed of the blower fan to decrease as the outside air temperature increases. apparatus.

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