JPH10205855A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stabilize the control of an air conditioner by a method wherein the operating capacity of a compressor is changed in accordance with a signal for stabilizing the room temperature of a room to be air-conditioned at an objective temperature for heating. SOLUTION: Upon heating operation, a microcomputer 55 receives a signal, showing heating operation, and data, showing required operating capacity, from an indoor unit 51 through a serial circuit 54 while the microcomputer 55 transfers the received signal to another microcomputer 59 as it is and, simultaneously, changes a four-way valve 7 into the condition of heating operation. Then, the microcomputer 59 outputs a control signal for operating a compressor 8 with a preset number of rotation into the microcomputer 55 while the microcomputer 55 operates the compressor 8 with the preset number of rotation in accordance with the signal from the microcomputer 59. Further, the amount of combustion of a burner is set based on an operating capacity, required by an indoor unit 51 and transferred from the microcomputer 55. Accordingly, stabilized operation, reduced in the fluctuation of temperature, can be effected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner having a refrigerant circuit and a refrigerant heating device for heating a refrigerant circulating in the refrigerant circuit.

[0002]

2. Description of the Related Art A conventional air conditioner is disclosed in Japanese Patent Application No. 7-6 / 1993.
There was one described in JP-A-564-564. What is described in this publication is a compressor, an indoor heat exchanger, a refrigerant heater (for example, a combustor), an outdoor heat exchanger,
When the indoor heat exchanger is used as a heat source for cooling by using the decompression device, the refrigerant discharged from the compressor is sequentially discharged from the outdoor heat exchanger, the decompression device, the indoor heat exchanger, and the compressor. A refrigerant circuit that circulates in order is configured, and when the indoor heat exchanger acts as a heat source for heating, the refrigerant discharged from the compressor is the indoor heat exchanger, the refrigerant heater, and the compressor in order. A refrigerant circuit that circulates in order is configured to enable a cooling operation and a heating operation by the indoor heat exchanger.

[0003]

In the air conditioner constructed as described above, the compressor is ON / OFF controlled at a constant speed, and the compressor is turned ON / OFF during the cooling operation.
The cooling operation is enabled by the FF control and the endothermic effect at the time of expansion of the refrigerant, and the heating operation is enabled by circulating the heated refrigerant to the indoor heat exchanger by the operation of the compressor during the heating operation. Had been done.

Therefore, the air conditioner only needs to control the ON / OFF of the compressor during the cooling operation, and control the amount of combustion of the refrigerant heater and the ON / OFF of the compressor during the heating operation. The combustion amount was controlled by adding a combustor to the ON / OFF control of the machine.
In such a configuration, since the compressor performs only the ON / OFF operation, the operation is intermittent, and the room temperature fluctuation width of the controlled room to be controlled becomes large, so that stable air conditioning cannot be performed.

Therefore, it has been considered that the compressor may be of a variable capacity type by using an inverter or the like for driving the compressor. However, when the control circuit of the existing inverter and the control circuit of the existing combustor are used together, In some cases, data was not exchanged between the two control circuits and hunting occurred in the control.

The present invention provides an air conditioner in which control is stabilized by performing overall control mainly by a control circuit of a combustor against such a problem.

[0007]

The present invention according to claim 1 comprises at least a variable capacity compressor, a use side heat exchanger, a refrigerant heater, a heat source side heat exchanger, and a pressure reducing device. When the use side heat exchanger is used as a cooling heat source, the refrigerant discharged from the compressor circulates in the order of the outdoor heat exchanger, the pressure reducing device, the use side heat exchanger, and the compressor. When such a refrigerant circuit is configured and the use side heat exchanger acts as a heat source for heating, the refrigerant discharged from the compressor sequentially circulates in the order of the use side heat exchanger, the refrigerant heater, and the compressor. When using the use-side heat exchanger as a heat source for cooling in an air conditioner configured with such a refrigerant circuit, the operating capacity of the compressor stabilizes the room temperature of the conditioned room at the target temperature for cooling. In response to a signal to cause When acting as a heat source for the refrigerant, the refrigerant at the outlet of the refrigerant heater is centered on the value converted from the signal for stabilizing the heating capacity of the refrigerant by the refrigerant heater at the room temperature of the conditioned room at the target temperature for heating. The temperature of the refrigerant in the refrigerant circuit is changed to be higher than the temperature of the refrigerant where the refrigerant is at a high pressure in a predetermined relationship, and the operating capacity of the compressor is set to the room temperature of the conditioned room. It has a control unit that changes in response to a signal for stabilizing at a temperature.

By providing such a configuration, a predetermined amount of heating can always be obtained with respect to the rotational speed of the compressor, which varies the amount of heating of the refrigerant.

According to a second aspect of the present invention, in an air conditioner having at least a compressor of a variable capacity type, a pulse signal in which an ON time is adjusted for an increase or decrease of a capacity required of the compressor based on a current operation state. And a capacity control means for increasing or decreasing the operating capacity of the compressor by a capacity based on the ON time of the pulse signal.

With such a configuration, the operation capability of the compressor can be set by the ON time of the pulse signal.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic view of an air conditioner of the present invention. In the figure, reference numeral 1 denotes an indoor heat exchange sensor, which is disposed so as to be able to detect the temperature of an indoor heat exchanger 2 (use side heat exchanger). Reference numeral 3 denotes an indoor fan, which circulates air in the room (the conditioned room) to the indoor heat exchanger 2. Therefore, when the indoor heat exchanger 2 is operating as a cooler, indoor cooling operation is performed, and when the indoor heat exchanger 2 is operating as a heater, indoor heating operation is performed. .

Reference numeral 4 denotes a room temperature sensor for detecting the temperature in the room (the temperature to be controlled in the conditioned room). Based on the temperature detected by the room temperature sensor 4 and an arbitrarily set temperature, the required operating capacity (cooling capacity, heating capacity) of the air conditioner is calculated and operated, and the air conditioner is operated with that capacity. Things.

Reference numeral 5 denotes a temperature sensor, which is provided in a refrigerant pipe connecting the indoor heat exchanger 2 to a compressor 8 via a four-way valve 7 and is mounted so as to detect the temperature of the refrigerant flowing inside.

The compressor 8 is of a variable capacity type in which the operating capacity is changed by changing the number of revolutions. As a means for changing the number of revolutions, an induction motor is used to change the frequency of AC power applied to the motor. There is a method using a DC motor and changing the voltage of DC power applied to the motor.

Reference numeral 9 denotes an accumulator, which is provided on the suction side of the compressor 8 so as to prevent the compressor 8 from sucking the liquid refrigerant, and performs gas-liquid separation of the gas-liquid mixed refrigerant.

A check valve 10 regulates the flow of the refrigerant. The check valve 10 flows the refrigerant from the four-way valve 7 to the accumulator 9 side. (Negative pressure generated by the operation of the compressor 8 causes the refrigerant to flow only to the accumulator 9 side.) 19 is an outdoor heat exchanger (heat source side heat exchanger) that can exchange heat with the outside air. Are located in The outdoor heat exchanger 19 and the indoor heat exchanger 2 are connected via a pressure reducing device (such as a capillary tube) 18 and a check valve 17, and the check valve 17 controls the refrigerant outdoor heat exchanger 1.
9 flows only in the direction of the indoor heat exchanger 2.
The outdoor heat exchanger 19 is provided with an outdoor blower 16 (consisting of at least a propeller fan and an electric motor) for promoting heat exchange with the outside air.

Reference numeral 15 denotes an electromagnetic on-off valve. When the valve is opened, the refrigerant is supplied to a refrigerant heater composed of the heat exchanger 22 and the burner 12, and then guided to the accumulator 10.

Reference numeral 13 denotes a combustion fan, which is driven by a motor and sends combustion air to the burner 12. The amount of combustion of the burner 12 can be changed by changing the amount of air blown by the combustion fan 13. Increasing the amount of air blow increases the amount of combustion, and decreasing the amount of air blow decreases the amount of combustion.

Reference numeral 14 denotes a temperature fuse which is cut off when the temperature in the refrigerant heater becomes abnormally high due to the combustion of the burner 12 to stop the combustion of the burner 12. Reference numeral 21 denotes a bimetal switch.
When the temperature inside the refrigerant heater becomes abnormally high due to the combustion of No. 2, the section is opened to output a signal for performing the protection operation. The operating temperature of the bimetal switch is set to be about 40 to 50 degrees lower than the fusing temperature of the thermal fuse 14, and a predetermined differential is set with respect to the operating temperature for returning the section. The thermal fuse 14 and the bimetal switch 21 are connected in series on the electric circuit, and are configured to perform a protection operation when any one of the components operates.

Reference numeral 23 denotes a proportional control valve, and reference numerals 24 and 25 denote electromagnetic opening / closing valves, which control the supply amount of gas supplied from the gas main stopper to the burner 12 and whether or not the gas can be supplied. The opening of the proportional control valve 23 is adjusted in accordance with the amount of air blown by the combustion fan 13 (the amount of air blown by the combustion fan may be adjusted in accordance with the degree of opening of the proportional control valve 23). The heater is energized when the heater is in the operating state to open the gas flow path.
Open the gas flow path during the combustion operation. When either the thermal fuse 14 or the bimetal switch 21 operates, the electromagnetic on-off valve 24 is configured to close the gas flow path first.

An exhaust port 20 discharges exhaust gas from the burner 12 to the outside of the machine. Reference numeral 6 denotes a pressure reducing device (such as a capillary tube) which is a protection circuit for releasing a part of the refrigerant on the high pressure side to the low pressure side when the high pressure in the refrigeration cycle exceeds a value set by the pressure reducing device 6. is there.

In the air conditioner configured as described above, the electromagnetic on-off valve 15 is opened during the heating operation, the four-way valve 7 is set to the state indicated by the solid line, the compressor 8 starts operating, and the burner 12 burns. By starting, the refrigerant heated in the heat exchanger 22 is sent to the indoor heat exchanger 2 via the accumulator 9 and the compressor 8 via the four-way valve 7 via the accumulator 9, and the temperature of the indoor heat exchanger 2 is reduced. Enhance. Therefore, the air heated by the indoor heat exchanger by operating the indoor fan 3 is supplied into the room, and the indoor heating operation is performed.

The refrigerant, the temperature of which has been lowered by blowing air in the indoor heat exchanger 2, is then guided to the refrigerant heater via the solenoid on-off valve 15 by the discharge pressure of the compressor 8 (or the negative suction pressure of the compressor 8). It is heated again by the burner 12. Thereafter, a continuous cycle of the heating operation is established by discharging the heated refrigerant again by the compressor 8, and the heating operation is continued.

At the time of cooling operation, the electromagnetic on-off valve 15 is closed, the four-way valve 7 is set to the state indicated by the dotted line, the compressor 8 starts operating, and the burner 12 stops burning, so that the compression through the accumulator 9 The refrigerant sucked by the machine 8
After being compressed by the compressor 8, it is supplied to the outdoor heat exchanger 19 via the four-way valve 7 (dotted flow path).

In this outdoor heat exchanger, the high-temperature and high-pressure gas refrigerant discharged from the compressor 8 exchanges heat with the outside air to lower the temperature and condense (liquefy). At this time, when the outdoor fan 16 operates, heat exchange between the outside air and the refrigerant is promoted, and the condensation of the refrigerant is assisted. Therefore, if the amount of air blown by the outdoor fan 16 is controlled based on the outside air temperature or the temperature after condensation of the refrigerant, it is possible to stabilize the refrigeration cycle by keeping the state of the refrigerant after condensation constant. .

The refrigerant condensed in the outdoor heat exchanger 19 is throttled by the pressure reducing device, sent to the indoor heat exchanger 2 via the check valve 17, and evaporated in the indoor heat exchanger 2. By blowing the indoor heat exchanger 2 cooled by the evaporation of the refrigerant to the indoor heat exchanger 2 with the indoor fan 3, the cooled air can be supplied to the room, and the indoor cooling operation can be performed.

The refrigerant after evaporation (a refrigerant in a gas-liquid mixed state where a liquid refrigerant remains from a completely gas state) is a four-way valve 7, a check valve 1
After being guided to the accumulator 9 again through 0, it is compressed again by the compressor 8 and the cycle of the cooling operation is continued.

FIG. 2 is a control circuit diagram (block diagram) for controlling the operation of the device shown in FIG. In this figure, reference numeral 51 denotes an indoor unit, on which the indoor heat exchanger 2, the indoor fan 3, the temperature sensors 1, 4 and the control circuit shown in FIG. 1 are mounted. The indoor unit 51 is connected by three lines (power line, common line, signal line), and power for operation is supplied from the indoor unit 51 via the power line and common line, and the microcomputer is connected via the signal line and common line. 55 and the control circuit of the indoor unit 51 are configured to exchange control signals and data.

From the control circuit of the indoor unit 51, control signals such as a signal mainly indicating a cooling operation / heating operation and a signal indicating an operation capability required by the indoor unit 51 are sent.
The operation capability is determined, for example, by detecting a difference e between the temperature detected by the temperature sensor 4 and the set temperature at predetermined intervals, and based on the difference e and a change Δe of the difference e, a fuzzy tune is optimally tuned in advance. A capacity correction value is obtained by performing a calculation, and the driving capacity after performing the capacity correction on the current driving capacity is set as a new driving capacity. Note that a look-up table calculated in advance may be used for the fuzzy calculation, and another calculation method (PI
D operation, neuro-fuzzy operation, etc.) can also be used.

Further, the operation of the indoor unit 51 includes normal control (operation function by a timer, automatic change function of the wind speed of the indoor fan, automatic change control function of the discharge direction of the harmonized air, display function, indoor heat exchange sensor (A protection function such as a high load protection control based on the temperature detected by the control unit 1 and an antifreeze control of the outdoor heat exchanger 2).

In FIG. 2, reference numeral 53 denotes a power supply circuit, which outputs a plurality of constant voltage powers based on the AC power supplied from the indoor unit 51. For example, microcomputers, various sensors, drive circuits, inverter circuits, valves, and the like. Further, the power supply circuit 53 is provided with a current detector, and the microcomputer 55 controls the current protection so that the current value detected by the current detector does not exceed a predetermined value so as to suppress the operation of a device that consumes a large amount of current. Is what you do.

Reference numeral 54 denotes a serial communication circuit, which is an interface circuit that enables the microcomputer 55 to receive a control signal transmitted from the indoor unit 51. The serial circuit 54 mainly includes a photocoupler and a switching transistor.

Reference numeral 56 denotes an inverter circuit. In response to a signal from the microcomputer 55, six switching elements connected in a three-phase bridge form are turned on / off and set to P.
The three-phase pseudo sine wave based on the WM theory is converted from the DC power supplied from the power supply circuit 53 and supplied to the driving three-phase induction motor of the compressor 8. If the frequency of the pseudo sine wave is changed, the rotation speed of the compressor 8 changes, and the operating capability of the compressor can be controlled.

When a brushless DC motor is used to drive the compressor 8, the motor is generated so that current always flows through a specific stator winding based on the rotational position of the rotor of the motor. The microcomputer 55 outputs the output signal from the microcomputer 55, and in response to this signal, the six switching elements connected in a three-phase bridge are respectively turned on / off to maintain the continuous rotation of the electric motor. Further, by chopping this signal output from the microcomputer 55 at a predetermined cycle and changing its ON duty, it is possible to change the pseudo voltage applied to the stator winding of the DC motor, thereby changing the rotation speed of the motor. Can be. That is, the operating capacity of the compressor can be controlled.

Reference numeral 57 denotes various sensors, for example, a temperature sensor for detecting the temperature of the refrigerant discharged from the compressor 8 and executing a protection operation by the microcomputer 55 when the temperature is high, and for detecting the outside air temperature. The microcomputer 55 is a temperature sensor for detecting the temperature of the temperature sensor and the inverter circuit 56 and executing the protection operation when the temperature is high. The outputs of these sensors are given to the microcomputer 55.

Reference numeral 59 denotes a microcomputer, which is connected to the microcomputer 55 so that control signals and data can be transmitted and received, and mainly controls the operation of the refrigerant heater.

Reference numeral 58 denotes various sensors.
Temperature sensors 5 and 11, temperature fuse 14, bimetal switch 21, burner 1
The output of these sensors is given to the microcomputer 59.

Reference numerals 60 and 61 denote drive circuits, respectively. The drive circuit 60 is a circuit for driving a step motor used for the proportional control valve 23. The drive circuit 61 is for controlling the number of rotations of the motor of the combustion fan 13. Circuit. The rotation speed of the motor of the combustion fan 13 is controlled by the compressor 8 described above.
A method similar to that of the rotation speed control described above can be used.

Numeral 62 denotes an igniter, and the burner 12
The operation of the microcomputer 59 is controlled by the microcomputer 59.

When performing a heating operation in the air conditioner configured as described above (when a signal indicating the heating operation and data indicating the required operation capability are transmitted from the indoor unit 51), first, the microcomputer 55 To the serial circuit 54
, And the received signal is transferred to the microcomputer 59 as it is. At the same time, the four-way valve 7 is changed to the heating operation state (the state indicated by the solid line in FIG. 2).

The microcomputer 59 outputs a control signal to the microcomputer 55 for closing the electromagnetic on-off valve 15 and operating the compressor 8 at a preset rotation speed. That is, an operation of recovering the refrigerant accumulated in the outdoor heat exchanger 19 is performed. The time of the refrigerant recovery operation is set in advance according to the capacity of the outdoor heat exchanger 19, and the time is set short within a predetermined time or under predetermined conditions.

The microcomputer 55 operates the compressor 8 at the set rotation speed in response to a signal from the microcomputer 59. By such an operation, the refrigerant in the refrigerant circuit is stored in the indoor heat exchanger 5.

Next, after completion of the refrigerant recovery operation, the compressor 8
The solenoid on-off valve 15 is opened with the operation of. At this time, a new rotation speed of the compressor 8 is initialized by the detection value Th1 of the temperature sensor 5.

The rotational speed initially set is Th1 = 10.
When the temperature is less than 90 degrees, the rotation speed is 90% of the maximum rotation speed and Th1 is 1.
When the angle is between 0 and 20 degrees, the rotation speed is 60% of the maximum rotation speed,
When Th1 exceeds 20 degrees, the rotation speed is 40% of the maximum rotation speed. These respective rotational speeds are arbitrarily set based on the capacity of the entire refrigerant circuit, the maximum operating capacity of the compressor 8, and the like, and are not limited thereto.

At the same time, combustion by the burner 12 is started. The combustion amount of the burner 12 is set based on the operation capacity required by the indoor unit 51 transferred from the microcomputer 55. The burner 12 is ignited by an igniter 62,
This is performed by a normal process using a frame rod or the like.

The amount of combustion of the burner 12 is first set based on a conversion table which is set in advance in a plurality of stages with respect to the operating capacity, and is then proportionally adjusted so that the temperature value detected by the temperature sensor 11 reaches the target temperature value Th2. Control valve and combustion fan 13
Is controlled by the microcomputer 59.

Although the conversion table is divided into 16 stages at substantially equal intervals in the present embodiment, the number of stages can be set arbitrarily according to the maximum combustion amount of the burner, and according to the combustion characteristics of the burner. It is not necessary that the intervals be equal.

The target temperature Th2 is set as follows based on the detected temperature value Th1 of the temperature sensor 5. Th2 =
(Th1 × a + b) ± α, where a, b, and α are constants and are set in advance based on the entire operation state.
Therefore, it is set based on the capacity of each heat exchanger, compressor, burner, and the like. Further, the change in the air flow rate of the proportional control valve and the combustion fan 13, that is, the change in the combustion rate of the burner 12, is performed in a predetermined cycle (10 seconds to 20 seconds in the present embodiment).
Every second).

When the operation capacity required by the indoor unit 51 changes, the amount of combustion set in the burner 12 changes. However, the microcomputer controls the temperature value detected by the temperature sensor 11 to reach the target temperature value Th2 again. As a result, the temperature value detected by the temperature sensor 11 is always stabilized at the target temperature value Th2.

The rotation speed of the compressor 8 is corrected as follows. The temperature value detected by the temperature sensor 11 is Th2
Is calculated based on the difference between the temperature value and Th2, and the correction value is transmitted to the microcomputer 55 to change the rotation speed of the compressor 8. The transmission cycle of the correction value to the microcomputer 55 at this time is set to be shorter (about 1 second) than the correction cycle of the combustion amount of the burner 12, so that the change in the rotation speed of the compressor 8 has priority over the change in the combustion amount of the burner 12. Is set to

By setting as described above, the optimum rotation speed of the compressor 8 can be always obtained according to the combustion amount of the burner 12. Actually, the rotation speed of the compressor 8 may activate the protection function by the output of various detectors (compressor temperature, current detected by a current detector, refrigerant temperature) input by the microcomputer 55. Depending on the type of the protection function, the rotation speed of the compressor 8 is maintained or reduced. At this time, the increase in the rotation speed of the compressor 8 is not corrected, but the increase in the combustion amount of the burner 12 is corrected later, so that the temperature detected by the temperature sensor 11 can be maintained at Th2.

FIG. 3 is a diagram showing a rotational speed correction signal of the compressor 8 output from the microcomputer 59 to the microcomputer 55. Period T (T = 1 second), ON duty t (t = 0% to 10
0%). t = 100% (H
Output level), the maximum correction value (10 rp)
m) and t = 0% (continuous output of L level), no correction is performed, and the resolution is set to 0.1 rpm. still,
Although the above description is based on the number of rotations of the compressor, when an induction motor is used as the drive source of the compressor, the number of rotations may be directly replaced with the frequency. In this case, the maximum correction value is 2 Hz / sec.
About c is desirable.

FIG. 4 is a diagram showing the characteristics of the correction, in which a correction value is obtained for the detection value detected by the temperature sensor 11. At Th2 ± 3 or more, the maximum value (max) is reached. When the direction of change of the detection value is reversed (decrease → increase, increase → decrease) in the range of Th2-1 to TH2 + 3, the ON duty is set to 0 and the correction of the rotation speed is completed. The correction is restarted when the detected value exceeds the range of Th2-1 or more and TH2 + 3 or less. FIG.
Can change the followability by changing the position where the correction value becomes maximum. For example, in FIG. 4, the correction value is maximum at Th2 + 3, but is Th2 + 1.
The correction value may be set to be maximum at 0.

Next, when performing the cooling operation, the microcomputer 55 switches the four-way valve 7 to the cooling operation side (the state shown by the dotted line in FIG. 1) in accordance with the cooling operation signal from the indoor unit 51. Since the signal from the indoor unit 51 is transferred to the microcomputer 59, the microcomputer 59 stops the combustion of the burner 12 and closes the electromagnetic switching valve 15 based on the signal.

The microcomputer 55 controls the number of revolutions of the compressor based on the operation capacity required from the indoor unit 51.

[0056]

According to the air conditioner thus configured,
In the configuration according to claim 1, the operating capacity of the air conditioner can be balanced with the load by changing the operating capacity of the compressor and the heating capacity of the refrigerant heater in accordance with the load of the conditioned room. This allows stable operation with little temperature fluctuation.

Further, according to the configuration of the second aspect, the increase / decrease value of the operating capacity of the compressor can be changed in an analog manner,
It is possible to change the driving ability in a short cycle.

[0058]

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an air conditioner showing an embodiment of the present invention.

FIG. 2 is a control circuit diagram (block diagram) for controlling the operation of the device shown in FIG.

FIG. 3 is a diagram showing a compressor rotation speed correction signal output from a microcomputer.

FIG. 4 is a diagram showing characteristics of correction.

[Explanation of symbols]

 2 Indoor heat exchanger 5, 11 Temperature sensor 7 Four-way valve 8 Compressor 12 Burner 18 Pressure reducing device 19 Outdoor heat exchanger

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Koto Akita 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Inventor Kazuya Sugiyama 2 Keihanhondori, Moriguchi-shi, Osaka 5-5-5 Sanyo Electric Co., Ltd. (72) Inventor Hiroshi Okumura 2-5-5 Sanyo Electric Co., Ltd., Sanyo Electric Co., Ltd. (72) Inventor Tadashi Ohata Keihanmoto, Moriguchi City, Osaka 2-5-5, Sanyo Electric Co., Ltd.

Claims (2)

[Claims] 1. A heat source for cooling a use side heat exchanger using at least a variable capacity type compressor, a use side heat exchanger, a refrigerant heater, a heat source side heat exchanger, and a decompression device. When acting as, a refrigerant circuit is configured such that the refrigerant discharged from the compressor circulates in the order of the outdoor heat exchanger, the pressure reducing device, the use side heat exchanger, and the compressor in this order, and the use side heat exchanger When acting as a heat source for heating, in an air conditioner having a refrigerant circuit configured such that the refrigerant discharged from the compressor sequentially circulates in the order of the use side heat exchanger, the refrigerant heater, and the compressor. When the use side heat exchanger acts as a heat source for cooling, the operation capacity of the compressor is changed in response to a signal for stabilizing the room temperature of the conditioned room at the target temperature for cooling, and the use side heat exchanger is changed. When using the exchanger as a heat source for heating, The temperature of the refrigerant at the outlet of the refrigerant heater becomes high in the refrigerant circuit around the value converted from the signal for stabilizing the heating capacity of the refrigerant due to the room temperature of the conditioned room at the target temperature for heating. The temperature of the refrigerant is changed so as to be higher than the temperature of the refrigerant in a predetermined relationship, and the operating capacity of the compressor is changed in response to a signal for stabilizing the room temperature of the conditioned room at the target temperature for heating. An air conditioner comprising a control unit. 2. An air conditioner having at least a variable capacity compressor, the ability to convert the increase / decrease value of the capacity required of the compressor based on the current operation state into a pulse signal whose ON time has been adjusted and calculate the value. Setting means and O of this pulse signal
An air conditioner comprising: capacity control means for increasing or decreasing the operating capacity of the compressor by a capacity based on N hours.