JP2007093113A - Heat pump type water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat pump type water heater for completing boiling-up in an estimated time by operating a compressor with its operating capability increased, when used for supplying hot water during boiling-up operation in a midnight power time zone. <P>SOLUTION: In the heat pump type water heater, an boiling-up operation time is calculated by dividing an amount obtained by subtracting the amount of remaining hot water from the capacity of a hot water storage tank 10 by a boiling-up amount per unit time to control boiling-up before a time for finishing a midnight power time zone. When a hot water temperature detecting sensor detects that hot water is supplied during boiling-up operation or a microcomputer 20 determines that a capability increase instructing switch is operated, the compressor 1 is controlled to be operated with the operating capability increased and reset to normal operating capability after the time for finishing the midnight power time zone passes. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention includes a refrigerant circuit that exchanges heat between a refrigerant compressed by a compressor capable of adjusting capacity and water using a heat exchanger for heating, a water storage tank and a heating heat exchanger using a circulation pump. The present invention relates to a heat pump type water heater provided with a hot water supply circuit that circulates between the hot water storage tanks and allows hot water to be discharged from the hot water storage tank. More specifically, the amount obtained by subtracting the amount of remaining hot water from the capacity of the hot water tank is divided by the amount of boiling per unit time to calculate the boiling operation time, so that the boiling time is raised before the end of the midnight power hours The present invention relates to a heat pump water heater to be controlled.

About the peak shift operation currently performed with the heat pump type hot water supply machine, it is indicated by patent documents 1 grade. This peak shift operation is performed by grasping the amount of remaining hot water in the hot water tank, calculating the amount of heat that needs to be heated, and calculating the operation time so that the boiling operation ends at the end of the midnight power time period.
JP 2003-139391 A

  However, if the hot water in the hot water tank is used for hot water supply etc. during this boiling operation, the boiling time calculated by the normal boiling operation capacity will be exceeded, and the midnight power hours will be exceeded. The situation that boiling is not completed at the end occurs.

  Therefore, the present invention, when used for hot water supply or the like while performing a boiling operation in the late-night power hours, operates with the compressor's operating capacity increased and boils within the expected time. The purpose is to complete the raising.

  For this reason, the first invention provides a refrigerant circuit for exchanging heat between refrigerant and water compressed by a compressor capable of capacity adjustment by a heat exchanger for heating, and water is stored in a hot water storage tank and the heating heat by a circulation pump. A hot water supply circuit that circulates between the hot water storage tanks and allows hot water to be discharged from the hot water storage tank, and subtracts the amount of remaining hot water from the capacity of the hot water storage tank and divides the amount by the amount of boiling per unit time for boiling operation. In a heat pump water heater that calculates time and controls to boil before the end of the midnight power time period, a detection device that detects that the amount of remaining hot water in the hot water tank has decreased during the boiling operation, and A control device is provided for controlling the operation so as to increase the operation capacity of the compressor when it is detected by the detection device that the amount of remaining hot water has decreased.

  According to a second aspect of the present invention, there is provided a refrigerant circuit for exchanging heat between refrigerant and water compressed by a compressor capable of adjusting the capacity by a heat exchanger for heating, a hot water tank for the water by a circulation pump, and the heat exchanger for heating. And a hot water supply circuit that allows hot water to be discharged from the hot water tank, and subtracts the amount of hot water from the capacity of the hot water tank to divide the amount by the amount of boiling per unit time to increase the boiling operation time. In a heat pump water heater that calculates and controls to boil before the end time of midnight power hours, a detection device that detects that hot water has been supplied during the boiling operation, and detection that hot water has been supplied by the detection device And a controller for controlling the compressor so that the compressor is operated with its operating capacity increased and the operation is returned to the normal operating capacity when the end time of the midnight power time period elapses. To.

  According to a third aspect of the present invention, in the heat pump type water heater according to the first or second aspect of the invention, the detection device is a detection sensor for detecting the amount of remaining hot water in the hot water storage tank.

  According to a fourth aspect of the present invention, there is provided a refrigerant circuit for exchanging heat between a refrigerant compressed by a compressor capable of adjusting capacity and water by a heat exchanger for heating, a hot water tank for the water by a circulation pump, and the heat exchanger for heating. And a hot water supply circuit that allows hot water to be discharged from the hot water tank, and subtracts the amount of hot water from the capacity of the hot water tank to divide the amount by the amount of boiling per unit time to increase the boiling operation time. In a heat pump water heater that calculates and controls to boil before the end time of the midnight power time period, an indication device for increasing the operating capacity of the compressor, and the compression by the indication device during the boiling operation And a controller for controlling the compressor so as to increase the operation capacity of the compressor when it is selected to increase the operation capacity of the compressor.

  According to a fifth aspect of the present invention, there is provided a refrigerant circuit for exchanging heat between a refrigerant and water compressed by a compressor capable of adjusting the capacity by a heat exchanger for heating, a hot water tank for the water by a circulation pump and the heat exchanger for heating. And a hot water supply circuit that allows hot water to be discharged from the hot water tank, and subtracts the amount of hot water from the capacity of the hot water tank to divide the amount by the amount of boiling per unit time to increase the boiling operation time. In a heat pump water heater that calculates and controls to boil before the end time of the midnight power time period, an indication device for increasing the operating capacity of the compressor, and the compression by the indication device during the boiling operation When an increase in the operating capacity of the machine is selected, the operating capacity of the compressor is increased to operate, and when the end time of the midnight power time period elapses or the instruction by the indicating device is canceled, the normal operating capacity Wherein the back by providing a control device for controlling to operate to.

  As described above, when the present invention is used in hot water supply or the like while performing a boiling operation in the late-night power hours, the operation time of the compressor is increased and the estimated time is increased. The boiling can be completed in the inside, and the boiling time can be shortened.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram of a circuit of a heat pump type hot water heater to which the present invention is applied. This heat pump type hot water heater has a refrigerant circuit R for exchanging heat between refrigerant and water compressed by a compressor using a heat exchanger for heating. The main configuration is a hot water supply circuit K that circulates water between the hot water storage tank and the heat exchanger for heating by a circulation pump and enables the hot water to be discharged from the hot water storage tank.

  The refrigerant circuit R includes a compressor 1 capable of adjusting the ability to suck and compress natural refrigerant such as carbon dioxide to high temperature and high pressure, a heating refrigerant-to-water heat exchanger 2 for exchanging heat between the refrigerant and water, an electric type Expansion valve 3, an evaporator 4 as an outdoor heat exchanger that performs heat exchange between outside air and refrigerant, an accumulator 5, and the like.

  The hot water supply circuit K is connected to a hot water storage tank 10 for storing hot water, a water pressure reducing valve 11 with a check valve for supplying tap water to the hot water storage tank 10, a hot water discharge pipe 12 for taking out hot water from the hot water storage tank 10, and the hot water discharge pipe 12. A pressure relief valve 13, a circulation pump 14 connected to the lower end of the hot water tank 10 to supply water from the hot water tank 10 to the refrigerant-to-water heat exchanger 2, and a flow rate adjusting valve 15 as a flow rate adjusting means. Have.

  Reference numeral 16 denotes a control board on which a microcomputer (hereinafter referred to as “microcomputer”) 20 is mounted as a control device for controlling the heat pump type hot water heater. 17 is a kitchen remote controller (remote controller) operated in the kitchen, and 18 is a bath remote controller (remote controller) operated in the bathroom. The kitchen remote controller 17 and the bathroom remote controller 18 are provided with a time display device, etc., and the kitchen remote controller 17 has a capability increase instruction switch (not shown) for increasing the operation capability of the compressor 1. When the capacity increase instruction switch is operated during the boiling operation, the microcomputer 20 that receives the operation signal controls to increase the operation capacity of the compressor 1 to operate.

  Next, description will be made based on the control block diagram of FIG. The microcomputer 20 includes a central processing unit (CPU) 21 that controls the operation related to the hot water supply of the heat pump type hot water heater, a random access memory (RAM) 22 as a storage device that stores various data, and a hot water supply operation. It comprises a ROM (Read Only Memory) 23 for storing such a program. Based on the data stored in the RAM 22, the CPU 21 controls the operation related to hot water supply of the heat pump type hot water heater according to the program stored in the ROM 23.

  The hot water storage tank 10 is provided with hot water temperature detection sensors TS1, TS2, TS3, and TS4. Since the water heater can be heated up to 55 ° C., the detected hot water temperature of each sensor is 55 ° C. In the above case, it is determined that there is remaining hot water. At this time, the detection sensor TS1 is disposed at a position where the remaining hot water amount is 220 liters, TS2 is also 180 liters, TS3 is 140 liters, and TS4 is 70 liters.

  Here, the capacity of the hot water storage tank 10 is 240 liters, the outside air temperature by the outside air temperature detection sensor 24 is 25 ° C., the heat pump capacity (the rated capacity of the compressor 1) is 5.0 kW, the boiling temperature is 75 ° C., the feed water temperature. The supply temperature of tap water supplied to the hot water storage tank 10 through the water pressure reducing valve 11 with a check valve by the sensor 25 is 20 ° C., the detection temperature of the hot water temperature detection sensor TS 3 is 63 ° C., and the detection temperature of the hot water temperature detection sensor TS 2 is Hereinafter, it will be described with reference to the flowchart of FIG. In the following description, these data are assumed to be stored in the RAM 22 of the microcomputer 20.

  That is, first, the microcomputer 20 searches for a combination of detection sensors including the boiling water temperature 55 ° C. between the two detection sensors from the four hot water temperature detection sensors, and detects a temperature higher than 55 ° C. The detection temperature of the detection sensor is Thi, the amount of remaining hot water is Lhi, the detection temperature of the detection sensor detecting a low temperature is Tlo, and the amount of remaining hot water is Llo. The microcomputer 20 calculates a remaining hot water amount Lz from Lz = (Thi−55) / (Thi−Tlo) × (Llo−Lhi) + Lhi.

  Therefore, the microcomputer 20 determines that the remaining hot water amount Lz reaching 55 ° C. is about 165 liters from (63−55) / (63−50) × (180−140) +140.

  Next, the circulation flow rate (boiling amount per minute) is calculated by dividing the heating amount per minute by the heat pump by the temperature obtained by subtracting the water temperature from the boiling temperature. Specifically, the circulation flow rate = (heat pump The microcomputer 20 calculates from the capacity P × 860 (Kcal) / 60 (minutes) / (boiling temperature Tp− (outside air temperature Tt × 0.8 + 3)), that is, the feed water temperature at which the predetermined capacity is constant (refrigerant vs. water). The water temperature entering the heat exchanger 2) is calculated from conversion formulas obtained in various performance tests using the outside air temperature value.

Therefore, the microcomputer 20 determines that the circulation flow rate is about 1.38 liters / minute from (5 × 860/60 / (75− (25 × 0.8 + 3)). ₂ ), when the boiling temperature is fixed and the feed water temperature (water temperature entering the refrigerant-to-water heat exchanger 2) rises, the heating capacity gradually decreases even if the frequency of the compressor 1 is kept constant, Since the curve of water temperature rise and capacity decline is not completely linear, the operation of lowering the frequency of the compressor 1 step by step according to the inlet water temperature, including the protection of the compressor 1 with this hot water heater, As a result, even if the inlet water temperature fluctuates, control is performed so as to perform an operation for maintaining a substantially constant circulation flow rate under the same outside air temperature condition.

  Next, based on the circulating flow rate calculated as described above, the required energization time is calculated as follows. That is, the amount obtained by subtracting the amount of hot water from the capacity of the hot water storage tank 10 is divided by the circulation flow rate to add 5 (allowance). Specifically, the required energization time is from (240-165) /1.38+5. It will be about 59 minutes.

  Next, the microcomputer 20 calculates the operation start time and stores it in the RAM 22. That is, the operation start time is 6:01, which is 59 minutes after the contract use time end time (end time of midnight power period) 7:00. When this operation start time is stored in the RAM 22 and a timer (not shown) in the microcomputer 20 measures the time, a boiling operation (peak shift operation) is started.

  When the microcomputer 20 determines that the hot water supply is not detected during the peak shift operation and the capacity increase instruction switch is not operated, the normal boiling operation (peak) with the capacity of the compressor 1 of 5.0 kW is performed. Shift operation) continues. Since the detected temperature of the hot water temperature detection sensor TS3 was 63 ° C. and the detected temperature of the hot water temperature detection sensor TS2 was 50 ° C., the remaining hot water amount Lz was calculated to be about 165 liters as described above. However, when hot water is supplied during the peak shift operation, the temperature detected by the hot water temperature detection sensor TS3 changes (decreases), so that it is possible to detect whether or not this hot water has been supplied.

  However, if the microcomputer 20 determines that the hot water supply has been detected during the peak shift operation or that the capacity increase instruction switch has been operated, the detected temperature of the outside air temperature detection sensor 24 is 7 ° C. to 25 ° C. It is judged by the microcomputer 20 whether or not it is within the range up to the following, and if it is not within the range, the normal boiling operation (peak shift operation) is continued, and if it is within the range, the hot water supply load is relatively light and compressed. The microcomputer 20 controls the frequency of the compressor 1 so that the capacity of the machine 1 is changed from 5.0 kW to 6.0 kW which is the maximum heating capacity.

  If the microcomputer 20 does not determine that the ability increase instruction switch provided on the kitchen remote controller 17 has been pressed again to cancel the instruction to increase the ability, or that the timer has timed the midnight power period, The ascending operation is continued. When the microcomputer 20 determines that the instruction to increase the capacity has been canceled or it has been timed that the midnight power time zone has been reached, it is then determined whether or not the boiling has ended.

  That is, when the hot water temperature detection sensor TS1 detects a temperature lower than 55 ° C., the microcomputer 20 determines that the boiling is not completed, and returns to the normal boiling operation, and performs the operation. It is determined that boiling has been completed, and the process ends.

  As described above, when the present invention is used in hot water supply or the like while performing a boiling operation in the late-night power hours, the operation time of the compressor is increased and the estimated time is increased. The boiling can be completed in the inside, and the boiling time can be shortened.

  In addition, when the detection temperature of the outside air temperature by the outside air temperature detection sensor 24 is 10 ° C. or less, the following operation time is corrected in order to take into account the reduction in the boiling capacity due to the stop of the boiling operation due to defrosting, etc. Also good. This correction value is derived based on experiments. The microcomputer 20 calculates the addition time to the boiling operation time based on the equation (−0.045 × outside air temperature + 0.45) × (240−remaining hot water amount).

  As a detection device for detecting that hot water has been supplied during the boiling operation (peak shift operation), detection for detecting the flow of hot water in the hot water discharge pipe 12 for taking out hot water from the hot water storage tank 10 is detected. A sensor may be provided.

  Although the embodiments of the present invention have been described above, various alternatives, modifications, and variations can be made by those skilled in the art based on the above description, and the various alternatives and modifications described above are within the scope of the present invention. Or a modification is included.

It is circuit explanatory drawing of a heat pump type water heater. It is a control block diagram. It is a figure which shows a flowchart.

Explanation of symbols

1 Compressor 2 Refrigerant to water heat exchanger (heat exchanger for heating)
10 Hot water tank 20 Microcomputer 22 RAM

Claims (5)

  A refrigerant circuit that exchanges heat between the refrigerant and water compressed by a compressor capable of adjusting the capacity with a heat exchanger for heating, and water is circulated between the hot water tank and the heat exchanger for heating by a circulation pump. And a hot water supply circuit that allows hot water to be discharged from the hot water storage tank, and calculates the boiling operation time by dividing the amount of hot water subtracted from the capacity of the hot water tank by the amount of boiling per unit time, and midnight power hours In a heat pump water heater that is controlled to boil before the end time of the belt, a detection device that detects that the amount of remaining hot water in the hot water tank is reduced during the boiling operation, and the amount of remaining hot water is reduced by this detection device. A heat pump type hot water heater, comprising: a control device that controls the compressor so as to increase the operation capacity of the compressor when it is detected.   A refrigerant circuit that exchanges heat between the refrigerant and water compressed by a compressor capable of adjusting the capacity with a heat exchanger for heating, and water is circulated between the hot water tank and the heat exchanger for heating by a circulation pump. And a hot water supply circuit that enables the hot water to be discharged from the hot water storage tank, and calculates the boiling operation time by dividing the amount of hot water subtracted from the capacity of the hot water tank by the amount of boiling per unit time, and midnight power hours In a heat pump type water heater that is controlled to be heated up before the belt end time, a detection device that detects that hot water has been supplied during the boiling operation, and the compressor that detects that hot water has been supplied by the detection device And a control device for controlling to return to the normal driving capacity when the end time of the midnight electric power time period elapses. Flop-type water heater.   The heat pump type water heater according to claim 1 or 2, wherein the detection device is a detection sensor for detecting a remaining hot water amount in the hot water tank.   A refrigerant circuit that exchanges heat between the refrigerant and water compressed by a compressor capable of adjusting the capacity with a heat exchanger for heating, and water is circulated between the hot water tank and the heat exchanger for heating by a circulation pump. And a hot water supply circuit that allows hot water to be discharged from the hot water storage tank, and calculates the boiling operation time by dividing the amount of hot water subtracted from the capacity of the hot water tank by the amount of boiling per unit time, and midnight power hours In a heat pump type water heater that is controlled to be heated up before the belt end time, an instruction device for increasing the operating capacity of the compressor, and the operating capacity of the compressor is increased by the indicating device during the boiling operation. A heat pump type hot water heater provided with a control device for controlling the compressor so as to increase the operation capability of the compressor when selected.   A refrigerant circuit that exchanges heat between the refrigerant and water compressed by a compressor capable of adjusting the capacity with a heat exchanger for heating, and water is circulated between the hot water tank and the heat exchanger for heating by a circulation pump. And a hot water supply circuit that enables the hot water to be discharged from the hot water storage tank, and calculates the boiling operation time by dividing the amount of hot water subtracted from the capacity of the hot water tank by the amount of boiling per unit time, and midnight power hours In a heat pump type water heater that is controlled to be heated up before the belt end time, an instruction device for increasing the operating capacity of the compressor, and the operating capacity of the compressor is increased by the indicating device during the boiling operation. When selected, the operation capacity of the compressor is increased to operate, and when the end time of the midnight power time period elapses or the instruction by the instruction device is canceled, the operation capacity is returned to the normal operation capacity. Heat pump water heater, characterized in that a control device for controlling the so that.

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