JPH0515942B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a hot water supply control device for a heat pump water heater.

Conventional technology Conventionally, in a heat pump type water heater having a hot water storage tank, when the hot water in the hot water storage tank is circulated by the city water pump to the hot water heating heat exchanger, the high pressure of the refrigerant is increased to a predetermined level. One method is to stop the compressor once the boiling temperature has reached the desired boiling temperature. The concept of terminating heat pump hot water supply operation at high pressure in this manner is disclosed in Japanese Patent Application Laid-open No. 122231/1983.

Problems to be Solved by the Invention However, with this control method that uniformly stops the heat pump hot water supply operation when the high pressure reaches a predetermined value, it is difficult to use a control method that uniformly stops the heat pump hot water supply operation when the high pressure reaches a predetermined value. If you operate the heat pump hot water supply when the temperature is high, the high pressure of the refrigerant will be high due to the above situation alone.
When the predetermined value is reached, it is determined that the boiling is complete.
In reality, there were cases in which the water in the hot water storage tank did not come to a boil.

In view of the above-mentioned problems, the present invention provides a control for a heat pump type water heater that can perform heat pump hot water supply operation and determine whether boiling is complete after sufficiently heating the city water, even when the outside temperature is high in summer and the city water temperature is high. It provides equipment.

Means for Solving the Problems In order to solve the above-mentioned problems, the control device for a heat pump water heater of the present invention, as shown in FIG. A control device for controlling the stop is provided, and this control device is connected to a pressure detection means for detecting the high pressure of the refrigeration cycle, and a plurality of set pressures P and R (P
<R); a second comparing means for comparing the set pressure with the high pressure detected by the pressure detecting means; a time counting means for counting the elapsed time; a set value time storage means, a third comparison means for comparing the set value K, and a set value time storage means, a third comparison means for comparing the set value K, and a means for controlling the operation of the outdoor fan when the high pressure is lower than P, stopping the outdoor fan when the high pressure is between P and R, and compressing when the high pressure is higher than R. mode storage means that stores the machine stop;
determining means for determining the state of high pressure based on the signals from the second comparing means and the third comparing means; selecting means for selecting the mode of the mode storage means based on the results of the determining means; It is composed of an output means for outputting a stop of the fan and a stop of the compressor, and stops the outdoor fan when the high pressure is higher than the set value P, and operates the outdoor fan when the high pressure is lower than P. When the elapsed time from operation or stop reaches the set value K, if the high pressure is less than the set value P, the outdoor fan is operated; if it is greater than or equal to P and less than R, the outdoor fan is stopped; In the above cases, the compressor is stopped.

Effects The present invention has the above-described configuration, and even when the outside temperature in summer is high and the city water temperature is high (approximately 30 degrees Celsius), the heat pump can supply hot water while repeating high and low pressure hunting due to the operation and stop of the outdoor fan. Only when operation can continue and the boiling water in the hot water storage tank has circulated to the hot water heating heat exchanger can accurate determination of completion of boiling be made.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 shows a row of heat pump water heaters equipped with the hot water supply control device of the present invention.

In Figure 2, 1 is a compressor, 2 is a hot water heating heat exchanger, 3 is an outdoor heat exchanger, 4 is an outdoor fan, 5
is a fan motor, 6 is a pressure reducer, 7 is a city water pump,
8 is a hot water storage tank, 9 is a pressure sensor, 10 is an outside temperature sensor, 11 is a timer, and 12 is a hot water supply control device, which are connected in sequence to form 13 heat pump water heaters. The pressure sensor 9 used as a pressure detection means is installed on the outlet side of the compressor 1 to detect the high pressure of the refrigerant, and the outside temperature sensor 10 used as an outside temperature detection means is installed on the windward side of the outdoor heat exchanger 3. It is provided in

The solid line arrow direction in the figure indicates the flow direction of the refrigerant during heat pump hot water supply operation, and the dashed line arrow direction indicates the circulation direction of city water. The high-pressure refrigerant gas exiting the compressor 1 is condensed in a hot water heating heat exchanger 2, which is a condenser, and gives heat to water sent from a hot water storage tank 8 by a city water pump 7. Then, it becomes a high-pressure refrigerant liquid,
The refrigerant is decompressed in the pressure reducer 6 and becomes a low-pressure refrigerant, absorbs heat from the outside air in the outdoor heat exchanger 3 which is an evaporator, becomes a low-pressure refrigerant gas, and returns to the compressor 1.

On the other hand, in the city water circuit, the water in the hot water tank 8 is circulated by the city water pump 7, receives heat from the hot water heating heat exchanger 2, and returns to the hot water tank as hot water. When it is summer and the outside temperature measured by the outside temperature sensor 10 is above A, the hot water supply control device 12 operates or stops the outdoor fan 4 and the compressor 1 according to input signals from the pressure sensor 9 and the timer 11.
The heat pump water heater is controlled by determining whether it is running or stopping.

Next, the configuration of the hot water supply control device 12 will be explained with reference to FIG.

In the figure, reference numeral 21 inputs an outside temperature detection signal from the outside temperature sensor 10, and a set outside temperature storage circuit 2.
a first comparison circuit that compares the set value A of 2;
25 is a second comparison circuit which inputs the high pressure detection signal from the pressure sensor 9 and compares it with the set values P and R of the set pressure memory circuit 24; 25 inputs the elapsed time detection signal from the timer 11 and compares the set value a third comparison circuit that compares the set value K of the time storage circuit 26;
0 is the signal SQ from the first, second, and third comparison circuits,
A determination circuit 28 comprehensively determines the high pressure situation from SP and ST, and 28 is a mode memory circuit 27 based on the signal from the determination circuit (when the high pressure is lower than P, the outdoor fan operates; between P and R, This is a selection circuit that selects which mode (stopping of the outdoor fan, stopping of the compressor if the temperature exceeds R). Mode memory circuit 2
7. The selection circuit 28 and the determination circuit 30 collectively constitute an arithmetic control section 31, which may be constituted by a so-called microcomputer. Reference numeral 29 is an output circuit that switches whether the outdoor fan 5 or the compressor 1 is operated or stopped based on a signal from the selection circuit 28. Further, the selection circuit 28 sends a signal to the timer 11 to start the timer 11 when the outdoor fan operation is selected to be stopped. It is assumed that the timer 11 is cleared when the elapsed time reaches K.

Here, the outside temperature sensor 10 is used as outside temperature detection means in FIG. 1, the pressure sensor 9 is used as pressure detection means, the timer 11 is used as time counting means, the first comparison circuit 21 is used as first comparison means, and the second comparison circuit 21 is used as The circuit 23 serves as a second comparison means, the third comparison circuit 25 serves as a third comparison means, the set outside temperature storage circuit 22 serves as a set value outside temperature storage means,
The set pressure memory circuit 24 has a set value pressure memory means,
The set time storage circuit 26 includes set value time storage means,
Each mode storage circuit 27 corresponds to mode storage means, the selection circuit 28 corresponds to selection means, the output circuit 29 corresponds to output means, and the determination circuit 30 corresponds to determination means.

FIG. 4 is a flowchart illustrating the operation of the hot water supply control device shown in FIG. 3 in more detail.

The operation of the hot water supply control device for the heat pump water heater shown in FIG. 2 will be described below with reference to FIGS. 3 and 4.

In summer, the outside temperature is detected by the outside temperature sensor 10,
The first comparison circuit 21 compares the set value A of the set outside temperature memory circuit 22 with 25°C, and if it is high, the pressure sensor 9 detects high pressure, and the set pressure memory circuit 24
The second comparison circuit 23 compares the set value P with the set value P, and when the value is higher, the outdoor fan 4 is stopped.

The outdoor fan 4 operates under conditions other than the above.

Now, the timer 11 detects the elapsed time after stopping the outdoor fan 4, and the third comparison circuit 25 compares the time with the set value K of the set time memory circuit 26. If the time is short, the outdoor fan continues to be stopped. , if they are the same, proceed to the next flow. Here, the timer 11 indicates the elapsed time K
It is assumed that the timer 11 is cleared when the timer 11 is reached.

That is, the pressure sensor 9 detects the high pressure, and the second comparison circuit 23 compares the high pressure with the set value P of the set pressure memory circuit 24. If it is low, the outdoor fan 4 is operated, and a loop is started in which the high pressure is detected again. Return.

When the value is high, the set value R is then compared to the second comparison circuit 2.
3, if the high pressure is low, the outdoor fan 4 is stopped and the loop returns to detecting the high pressure again, but if it is high, the compressor 1 is stopped as boiling is completed.
to stop. However, the operation and stop of the outdoor fan 4 and the compressor 1 are controlled by the first, second, and third comparison circuits 21 and 2.
The determination circuit 30 comprehensively determines the signals SQ, SP, and ST of the signals SQ, SP, and ST of the signals SQ, SP, and ST of the signals SQ, SP, and ST.

By controlling as above, when the outside temperature is high in summer and the city water temperature is also high (approximately 30℃)
However, due to the repeated operation and stop of outdoor fan 4,
It is possible to continue heat pump hot water supply operation while repeating high and low pressure hunting. Furthermore, if the boiling city water in the hot water storage tank 8 circulates to the hot water heating heat exchanger 2, the high pressure will become higher than the higher set value R even if the outdoor fan 4 is stopped. The heat pump water heater 13 can be stopped only when it is accurately determined that boiling is complete. However, heat pump hot water supply control during winter and intermediate periods when the outside temperature is lower than the set value can be done using the conventional boiling completion method using high pressure, and it is necessary to continue hot water supply operation while operating and stopping the outdoor fan as described above. There isn't.

In the embodiment, a heat pump type water heater with a hot water storage tank has been described, but even if there is no hot water storage tank, the same operating method as above may be used, and only an appropriate method for determining whether boiling is complete may be used. In this embodiment, the outside temperature is also used as a criterion, but the operation and stop of the outdoor fan and compressor may be controlled only by the high pressure and the elapsed time.

Effects of the Invention As described above, the hot water supply control device for a heat pump type water heater of the present invention configures a refrigeration cycle by a compressor, an outdoor heat exchanger, a hot water heating heat exchanger, and a pressure reducer, and A heat pump type water heater that supplies hot water using a heat pump is provided with a control device that controls the stoppage of the outdoor fan and the stoppage of the compressor, and this control device is connected to a pressure detection means that detects the high pressure of the refrigeration cycle, and a plurality of settings. Pressure P・
a set value pressure storage means storing R (P<R);
a second comparison means for comparing the set pressure and the high pressure detected by the pressure detection means; a time counting means for counting the elapsed time; a set value time storage means for storing the set time K; A third comparing means is used to operate the outdoor fan when the high pressure is lower than P, stop the outdoor fan between P and R, and R.
In the above, there is a mode storage means that stores the stop of the compressor, a determination means that determines the high pressure situation based on the signals of the second comparison means and the third comparison means, and a mode of the mode storage means according to the result of the determination means. and an output means for outputting a stop of the outdoor fan and a stop of the compressor according to a signal from the selection means, and the high pressure is set to the set value P.
At the above times, the outdoor fan is stopped, and when it is smaller than P, the outdoor fan is operated, and when the elapsed time from the selection of operation or stop of the outdoor fan reaches the set value K, the high pressure is set at the set value. This device is equipped with a control device for a beat pump water heater that operates the outdoor fan when it is less than P, stops the outdoor fan when it is more than P and less than R, and stops the compressor when it is more than R. Even when the outside temperature is high in summer and the city water temperature is high (approximately 30℃), heat pump hot water supply operation can be continued by repeatedly starting and stopping the outdoor fan and repeatedly hunting high and low pressures. can. Furthermore, if the boiling city water in the hot water storage tank is circulated to the hot water heating heat exchanger,
Even if the outdoor fan is stopped, the high pressure remains higher than the higher set value R, and only in this case can an accurate determination that boiling is complete be made and the heat pump type water heater be stopped.

[Brief explanation of the drawing]

FIG. 1 is a complaint response diagram showing the control device for the heat pump type water heater of the present invention as a function realizing means;
Fig. 2 is a block diagram showing an example of a heat pump type water heater equipped with the same control device, Fig. 3 is a block diagram of a control device for a heat pump type water heater which is an embodiment of the present invention, and Fig. 4 is a block diagram of the same control device. 1 is a flowchart illustrating the operation of the device in detail. 9...Pressure sensor, 10...Outside temperature sensor, 1
1...Timer, 12...Hot water supply control device, 21...
...first comparison circuit, 22...set outside temperature storage circuit,
23... Second comparison circuit, 24... Set pressure memory circuit, 25... Third comparison circuit, 26... Set time memory circuit, 27... Each mode memory circuit, 28... Selection circuit, 29... Output Circuit, 30... Judgment circuit,
31... Arithmetic control unit.

Claims (1)

[Claims] 1 Compressor, outdoor heat exchanger, hot water heating heat exchanger,
A heat pump type water heater that configures a refrigeration cycle using a pressure reducer and supplies hot water using the hot water heating heat exchanger is provided with a control device that controls the stoppage of the outdoor fan and the stoppage of the compressor. pressure detection means for detecting the high pressure of the cycle; set value pressure storage means for storing a plurality of set pressures P·R (P<R); and a pressure detection means for comparing the set pressure with the high pressure detected by the pressure detection means. 2 comparing means, a time counting means for counting the elapsed time, a set value time storage means for storing the set time K, a third comparing means for comparing the set value K, and a third comparing means for comparing the set value K with the high pressure P.
When the pressure is lower, the outdoor fan is operated, between P and R, the outdoor fan is stopped, and when it is higher than R, the compressor is stopped. determining means for determining the pressure situation; and selecting means for selecting the mode storage means mode based on the result of the determining means;
comprising an output means for outputting a stop of operation of the outdoor fan and a stop of the compressor according to a signal from the selection means,
When the high pressure is higher than the set value P, the outdoor fan is stopped, and when it is lower than P, the outdoor fan is operated, and when the elapsed time from the operation or stop of the outdoor fan reaches the set value K, the high pressure When the pressure is lower than the set value P, the outdoor fan is operated at P
A control device for a heat pump type water heater that stops an outdoor fan when the value is less than R, and stops a compressor when it is more than R.