JPS634105B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to current limitation during refrigerant removal operation control in an air conditioner comprising a heat pump refrigeration cycle equipped with an evaporative refrigerant heater that improves heating capacity at low outside temperatures. .

Generally, in this type of air conditioner, when the air conditioner is stopped from a refrigerant heating operation state and then the refrigerant heating operation is restarted after the evaporative refrigerant heater has warmed up, the accumulation of water in the outdoor heat exchanger occurs. Refrigerant removal control is performed to remove the refrigerant and create a stable refrigeration cycle. However, in this case, since the evaporative refrigerant heater is in a warm state, the pressure increases due to preheating, increasing the pressure difference between the discharge and suction of the compressor. The drawback was that when electricity was applied to the heater that vaporized the liquid fuel in the refrigerant, a specified current was generated, making it impossible to continue normal refrigerant heating operation.

Therefore, in order to eliminate the above-mentioned drawbacks, the present invention has the following features:
A pressure detection device is provided in the refrigeration cycle in which the pressure increases during refrigerant removal, and the heater and indoor blower are controlled by connecting the relay contact of this pressure detection device to a control device. In other words, if you drain the refrigerant while the evaporative refrigerant heater is still warm, the pressure will rise, and as soon as this pressure reaches the set pressure, the control device will operate and the heater will stop, and the indoor blower will turn on. The pressure is lowered to keep it within the specified current.

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

In the figure, 1 is a compressor, 2 is a four-way switching valve,
3 is an indoor heat exchanger, 4 is a pressure reduction mechanism, 5 is a check valve that passes refrigerant during cooling, 6 is an outdoor heat exchanger, 7 is a check valve, 8 is the flow of refrigerant during refrigerant heating operation and cooling operation 9 is a vaporizing refrigerant heater that heats the return pipe to the compressor 1, and this vaporizing refrigerant heater 9 includes a heat medium 9a such as water and heats the heat medium 9a. There is a heating device. In this heating device, 15 is a combustion fan, 16 is a rotating plate, and 17 is a motor interlocked with the combustion fan 15 and the rotating plate 16. 18 is a pipe provided to spray liquid fuel onto the rotary plate 16; 19 is an on-off valve that controls the supply of liquid fuel flowing through the pipe 18; 20 is a heater;
is a spark plug, and 22 is an exhaust port. 10 is an on-off valve that connects the discharge side and suction side of the compressor 1. 11 and 12 are an indoor blower and an outdoor blower, respectively. 23 is a pressure detection device that detects the refrigerant pressure in the refrigeration cycle. A refrigeration cycle is constructed by connecting these in a ring as shown in the figure. Here, 24 is a control device that controls the compressor 1, indoor blower 11, outdoor blower 12, four-way switching valve 2, on-off valves 8, 10, 19, motor 17, spark plug 21, and heater 20, each of which is controlled by a relay. They are connected as shown in FIG. That is, compressor 1, four-way switching valve 2, on-off valves 8, 10, indoor blower 11, outdoor blower 12, motor 17, on-off valve 19, heater 2
0, the spark plug 21 has a relay contact 1a, respectively.
2a, 8a, 10a, 11a, 12a, 17a,
19a, 20a, and 21a are connected in series, and these series circuits are connected in parallel with each other.

In the above configuration, during cooling operation, the refrigerant discharged from the compressor 1 is transferred to the four-way switching valve 2, the outdoor heat exchanger 6, the check valve 5, the pressure reducer 4, the indoor heat exchanger 3, the four-way switching valve 2, A refrigeration cycle is configured in which the refrigeration cycle passes through the check valve 7 and returns to the compressor 1.

Next, when performing a refrigerant heating operation using the vaporization type refrigerant heater 9, the refrigerant flows into the compressor 1, the four-way switching valve 2, the indoor heat exchanger 3, the on-off valve 8, and the vaporization type refrigerant heater 9. A refrigeration cycle returning to the compressor 1,
Two cycles are constructed: a refrigeration cycle from the compressor 1, passing through the on-off valve 10 and returning to the compressor 1. However, in the case of refrigerant heating operation, the refrigerant does not pass through the outdoor heat exchanger 6 due to the check valves 5 and 7. Further, at the same time as the refrigerant heating operation, the heater 20 is also energized until the temperature of the heater 20 rises to a certain level or higher.

Here, when starting the refrigerant heating operation using the evaporative refrigerant heater 9, in order to obtain a stable refrigeration cycle,
It is necessary to remove the refrigerant accumulated in the outdoor heat exchanger. This refrigerant removal control method first closes the on-off valves 8 and 10 for a certain period of time, and then the refrigerant accumulated in the outdoor heat exchanger 6 is removed by the four-way switching valve 2, the check valve 7,
Through the compressor 1, a four-way switching valve 2, an indoor heat exchanger 3
When passing through, the on-off valve 8 and check valve 5 cause
The refrigerant does not flow any further and eventually accumulates inside the indoor heat exchanger 3. Further, the refrigerant that had accumulated in the vaporization type refrigerant heater 9 also accumulates inside the indoor exchanger 3. After this refrigerant removal control is completed, the motor 17 is operated to rotate the combustion fan 15 and the rotary plate 16, and at the same time, the on-off valve 19 is opened and the liquid fuel flows from the piping 18 to the rotary plate 16 and is stirred into mist. When the state is reached, the heater 20 vaporizes the spark plug 21.
ignited by. Note that the indoor blower 11 is used to prevent cold air from blowing out when the refrigerant heating operation starts.
The operation is stopped for a certain period of time or until the pressure detection device 23 reaches the set pressure.

Normally, refrigerant extraction control is performed in a cold state, that is, when the vaporization type refrigerant heater 9 is cold, because there is no preheating in the vaporization type refrigerant heater 9, no heat is given to the refrigerant, and therefore the refrigerant extraction control is performed. Even if the pressure does not rise and the heater 20 is energized,
The current does not rise, so it stays within the specified limits.

However, when performing refrigerant heating operation in a hot state, that is, in a state where the vaporizing refrigerant heater 9 has once warmed up, there is preheating in the vaporizing refrigerant heater 9 during refrigerant extraction control, so the amount of heat in the refrigerant increases. Given. Therefore, when the pressure increases during the refrigerant extraction control and the pressure detection device 23 reaches the set pressure, the heater 20 is stopped and the indoor blower 11 is operated at the same time to radiate heat.

In this way, by stopping the heater 20 and operating the indoor blower 11 using the pressure detection device 23, the current consumption of the entire air conditioner is kept within the specified current, and stable refrigeration cycle operation is achieved. Can continue.

As is clear from the description of the embodiments above, the heating operation control method for an air conditioner according to the present invention connects the discharge pipe and suction pipe of a compressor to a four-way switching valve, connects an indoor heat exchanger to the four-way switching valve, A series circuit of a pressure reducing device and a cooling check valve and an outdoor heat exchanger are connected, and one end is connected between the indoor heat exchanger and a series circuit of the pressure reducing device and a cooling check valve. The other end of the series circuit of the first on-off valve and the vaporizing refrigerant heater was connected to the suction pipe of the compressor, and the discharge pipe and suction pipe of the compressor were connected via the second on-off valve. When the refrigerant heating operation of the refrigeration cycle is started, the first and second on-off valves are closed for a certain period of time to recover the refrigerant accumulated in the outdoor heat exchanger into the refrigeration cycle,
When the pressure detection device installed in the refrigeration cycle detects the set pressure, it cuts off the power to the heater installed in the evaporative refrigerant heater and energizes the indoor blower. , a stable refrigeration cycle can be obtained without exceeding the set pressure, and since the current is within the specified range, a wire with a small current capacity can be used, and the power consumption is low, furthermore, the specified current breaker will not trip unstably. There are various effects such as the fact that the warm-up operation does not stop during operation, and so on.

[Brief explanation of the drawing]

FIG. 1 is a refrigeration cycle diagram of an air conditioner controlled by a heating operation control method according to an embodiment of the present invention, and FIG. 2 is a partial electrical circuit diagram of the air conditioner. DESCRIPTION OF SYMBOLS 1... Compressor, 2... Four-way switching valve, 3... Indoor heat exchanger, 4... Pressure reduction mechanism, 5... Check valve, 6...
...Outdoor heat exchanger, 7...Check valve, 8...Opening/closing valve,
9... Evaporative refrigerant heater, 10... Opening/closing valve, 11
... Indoor blower, 20 ... Heater, 23 ... Pressure detection device.

Claims (1)

[Claims] 1 Connect the discharge pipe and suction pipe of the compressor to a four-way switching valve, connect an indoor heat exchanger, a series circuit of a pressure reducing device and a cooling check valve, and an outdoor heat exchanger to the four-way switching valve, and One end is connected between the heat exchanger and the series circuit of the pressure reducing device and the cooling check valve, and the other end of the series circuit of the first on-off valve and the evaporative refrigerant heater is connected to the compressor. At the start of a refrigerant heating operation of a refrigeration cycle in which the compressor is connected to a suction pipe and the discharge pipe and suction pipe of the compressor are connected via a second on-off valve, the first and second on-off valves are closed for a certain period of time. When the refrigerant accumulated in the outdoor heat exchanger is recovered into the refrigeration cycle, a pressure detection device provided in the refrigeration cycle is set to send the refrigerant to the heater provided in the vaporization type refrigerant heater that vaporizes liquid fuel. A heating operation control method for an air conditioner that cuts off electricity to the air conditioner and turns on electricity to an indoor blower.