JP2014020583A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner capable of achieving comfortable temperature/humidity.SOLUTION: An air conditioner configures a refrigeration cycle by: a compressor 23; a heat exchanger 27 for condensation; an expansion valve 17; and a heat exchanger 7 for evaporation. The air conditioner includes: an indoor blower 11 for blowing air passing through the heat exchanger 7 for evaporation to the indoors; indoor air temperature setting means (not shown) for outputting a desired indoor air temperature as an indoor air temperature setting value; and piping temperature setting means (not shown) for setting the dew point temperature of the air having desired partial water vapor pressure in the indoors as a target value of the piping temperature and outputting it. The lower temperature between an inlet temperature and an outlet temperature of the heat exchanger 7 for evaporation is made to be an evaporation temperature, and if the difference between the indoor air temperature and the indoor air temperature setting value is within a predetermined range, and also, the evaporation temperature is equal to or less than the target value, the outlet temperature is increased until it becomes equal to or more than the target value and less than the indoor air temperature. Then, the opening of the expansion valve 17, a rotational frequency of the compressor 23 and the air quantity of the indoor blower 11 are controlled in such a manner that the evaporation temperature is held within the predetermined range.

Description

  The present invention relates to an air conditioner that dehumidifies indoor air using a refrigeration cycle.

  Conventionally, in an air conditioner having a compressor, a heat exchanger for condensation, an expansion valve, an indoor heat exchanger, and a pipe through which refrigerant flows by connecting these, indoor air can be used by using a humidity sensor in addition to a temperature sensor. There is a configuration in which the rotational speed of the compressor is controlled using temperature and relative humidity as control targets. For example, a conventional air conditioner as described in Patent Document 1 includes a wet bulb temperature detection unit including a temperature sensor and a humidity sensor, and a wet bulb temperature setting unit that sets the wet bulb temperature of room air. There are some which control the rotational speed of the compressor so as to reduce the difference between the wet bulb temperature by the wet bulb temperature detecting means and the wet bulb temperature set value by the wet bulb temperature setting means. Further, the air conditioner includes temperature setting means and humidity setting means, and controls the rotational speed of the blower so that the difference between the temperature / humidity set value and the room temperature / humidity becomes small.

JP 2006-266677 A

  However, since the conventional air conditioner as described in Patent Document 1 requires a humidity sensor, there is a problem that the manufacturing cost of the air conditioner is increased, and the relative humidity with a desired humidity as a control target. In the configuration in which the humidity control is performed, for example, when the indoor relative humidity of 50% rh is achieved and the indoor air relative humidity of 50% rh is achieved, if the indoor air temperature is different at this time, the relative humidity is 50% rh. Despite the same index value, there is a problem that thermal effects on the human body are not equivalent.

  In terms of thermophysiology, a thermal equilibrium state is established between the human body and the air, and the state where the physiological burden associated with body temperature regulation is the smallest is said to be the thermal neutral state, which is a condition of comfort in the indoor environment. It has become. The water vapor partial pressure on the indoor air side when the average human body is in this thermal neutral state is about 20 hPa. When the average temperature and relative humidity in the boundary layer on the human body surface are 33 ° C. and 100% rh, respectively, the water vapor partial pressure is about 50 hPa. is there. The movement of moisture from the human body to the air side, which occurs depending on the water vapor partial pressure difference, is not perceived sensorially, so it is called insensitive steaming, and bears the latent heat of heat release from the human body.

  In the relative humidity control, even if the air temperature is 29 ° C. even at the same 50% rh, it is 20 hPa, and if the air temperature is 27 ° C., the pressure difference is about 18 hPa. It expands to about 7%. Thermal equilibrium is maintained against the sensible heat difference in the environment of 29 ° C. and 27 ° C. due to expansion or contraction of the skin blood vessels.

On the other hand, the thermal equilibrium of insensitive digestion is maintained at 30 hPa, which is an appropriate water vapor partial pressure difference at 29 ° C., but collapses at an indoor air temperature of 27 ° C., resulting in an increase in latent heat transfer due to moisture evaporation on the body surface. . This heat dissipation can also contribute to “cooling” when using the air conditioner and avoiding cooling. In the control that targets a constant relative humidity as in the conventional air conditioner described in Patent Document 1, the influence of the relative humidity on the human body differs depending on the room air temperature, and the set value of the room air temperature is relatively low. When it is low, there is a problem that the balance of insensitive digestion is lost, latent heat transfer is increased, and the body is excessively cooled.

  When it is necessary to promote heat dissipation from the human body, there is no problem with relative humidity control. However, in a human body that has been exposed to an air-conditioning environment for a long time or has sweated and is in a heat neutral state, the latent heat transfer due to insensitive steaming must be kept in equilibrium. Insensitive steaming is also difficult to perceive sensibly and cannot be physiologically controlled by humans. Therefore, the equilibrium state of latent heat transfer due to insensitive digestion is characterized by being largely dependent on air conditioning.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object thereof is to provide an air conditioner that can maintain a constant partial pressure of water vapor in indoor air and realize a comfortable temperature and humidity.

  In order to solve the above-described conventional problems, an air conditioner according to the present invention includes a compressor having a variable rotation speed, a condensing heat exchanger, an expansion valve, and an evaporating heat exchanger coupled by a refrigerant pipe, A refrigeration cycle is configured by circulating a refrigerant in the pipe, and is installed on the leeward side of the evaporating heat exchanger, and blowing means for sending air taken in through the evaporating heat exchanger into the room is input. Indoor air temperature setting means for outputting a desired indoor air temperature as the indoor air temperature set value, indoor air temperature detection means for detecting the indoor air temperature, and first pipe temperature for detecting the inlet temperature of the evaporating heat exchanger Detection means, second piping temperature detection means for detecting the outlet temperature of the evaporating heat exchanger, and a dew point temperature of air having a desired water vapor partial pressure in the room is set and output as a target value of the piping temperature. Piping temperature And a heat pump control means, wherein the heat pump control means uses a lower one of the inlet temperature and the outlet temperature as an evaporation temperature, and a difference between the indoor air temperature and the indoor air temperature set value is within a predetermined range. And after the first step of raising the outlet temperature until the temperature is equal to or higher than the target value and lower than the indoor air temperature when the evaporation temperature is equal to or lower than the target value, the evaporation temperature is set to the predetermined value. In order to execute the second step of maintaining within the range, the opening of the expansion valve, the rotation speed of the compressor, and the air volume of the blowing means are controlled, during the cooling operation, The indoor air temperature detected by the indoor air temperature detecting means is compared with the indoor air temperature set value, and when the indoor air temperature reaches the indoor air temperature set value, the evaporation of the heat exchanger for evaporation installed indoors Warm However, if it falls below the target value of the pipe temperature, which is the desired dew point temperature, the heat pump control means first reduces the opening of the expansion valve, and can quickly increase the outlet temperature to a temperature not less than the target value and less than the indoor air temperature. it can.

  At this time, the outlet temperature can be increased more quickly by simultaneously increasing the air volume of the blowing means. As a result, the air conditioner according to the present invention can quickly increase the piping temperature to alleviate dehumidification. That is, when the dew point temperature of the indoor air is lower than the desired dew point temperature, the air conditioner can quickly shift to high sensible heat ratio cooling with a high sensible heat ratio, and can reduce dehumidification.

  If the dew point temperature of the indoor air exceeds the desired dew point temperature, it is possible to dehumidify until the desired dew point temperature is reached, and the air conditioner brings the dew point temperature of the room air closer to the target dew point temperature. Is possible. In addition, when the heat pump control means increases the opening of the expansion valve and increases the number of rotations of the compressor, the air volume correction means increases the blown air volume, so that the cooling capacity is maintained and the rise in room temperature is suppressed. However, dehumidification can be mitigated by raising the piping temperature. That is, when the dew point temperature of indoor air is lower than the desired dew point temperature, the air conditioner can quickly dehumidify and shift to high sensible heat ratio cooling with a high sensible heat ratio.

In addition, when the dew point temperature of indoor air is constantly kept constant, the water vapor partial pressure in the air is also constant, thus preventing the water vapor partial pressure difference from the body surface boundary layer from expanding to a substantially constant level. be able to. In particular, it is possible to prevent excessive cooling at the hands and toes with a large surface area per unit volume, and it is possible to achieve a comfortable temperature and humidity by keeping the water vapor partial pressure of the room air constant without mounting a humidity sensor.

  The air conditioner of the present invention compares the indoor air temperature detected by the indoor air temperature detection means and the indoor air temperature set value during the cooling operation, and the indoor air temperature reaches the indoor air temperature set value. If the evaporation temperature of the evaporator installed indoors falls below the target value of the pipe temperature, which is the desired dew point temperature, the heat pump control means first throttles the expansion valve opening, and the evaporator outlet temperature is equal to or higher than the target value. The temperature can be quickly raised to a temperature lower than the room air temperature. At the same time, the evaporator outlet temperature can be increased more quickly by simultaneously increasing the air volume of the blowing means. As a result, the air conditioner according to the present invention can quickly increase the piping temperature to alleviate dehumidification. That is, when the dew point temperature of the indoor air is lower than the desired dew point temperature, the air conditioner can quickly shift to high sensible heat ratio cooling with a high sensible heat ratio, and can reduce dehumidification.

  If the dew point temperature of the indoor air exceeds the desired dew point temperature, it is possible to dehumidify until the desired dew point temperature is reached, and the air conditioner brings the dew point temperature of the room air closer to the target dew point temperature. Is possible. In addition, when the heat pump control means increases the opening of the expansion valve and increases the number of rotations of the compressor, the air volume correction means increases the blown air volume, so that the cooling capacity is maintained and the rise in room temperature is suppressed. However, dehumidification can be mitigated by raising the piping temperature. That is, when the dew point temperature of indoor air is lower than the desired dew point temperature, the air conditioner can quickly dehumidify and shift to high sensible heat ratio cooling with a high sensible heat ratio.

  In addition, when the dew point temperature of indoor air is constantly kept constant, the water vapor partial pressure in the air is also constant, thus preventing the water vapor partial pressure difference from the body surface boundary layer from expanding to a substantially constant level. be able to. In particular, it is possible to prevent excessive cooling at the hands and toes with a large surface area per unit volume, and it is possible to achieve a comfortable temperature and humidity by keeping the water vapor partial pressure of the room air constant without mounting a humidity sensor.

The block diagram of the air conditioning apparatus which concerns on Embodiment 1 of this invention. Flow chart leading to dehumidification mitigation operation of the air conditioner

According to a first aspect of the present invention, a compressor having a variable rotation speed, a condensing heat exchanger, an expansion valve, and an evaporating heat exchanger are coupled by a refrigerant pipe, and a refrigerant is circulated in the refrigerant pipe to constitute a refrigeration cycle. , Installed on the lee side of the evaporating heat exchanger, and blowing means for sending the air taken in through the evaporating heat exchanger into the room, and the input desired indoor air temperature is output as the indoor air temperature set value Indoor air temperature setting means, indoor air temperature detection means for detecting indoor air temperature, first pipe temperature detection means for detecting the inlet temperature of the evaporating heat exchanger, and outlet temperature of the evaporating heat exchanger A second pipe temperature detecting means for detecting the temperature, a pipe temperature setting means for setting and outputting a dew point temperature of air having a desired water vapor partial pressure in the room as a target value of the pipe temperature, and a heat pump control means, Hi The pump control means uses the lower of the inlet temperature and the outlet temperature as the evaporation temperature, the difference between the indoor air temperature and the indoor air temperature set value is within a predetermined range, and the evaporation temperature is the target When the temperature is equal to or lower than the value, after the first step of increasing the outlet temperature to be equal to or higher than the target value and lower than the indoor air temperature, the second step of maintaining the evaporation temperature within the predetermined range is executed. As described above, the opening degree of the expansion valve, the rotation speed of the compressor, and the air volume of the blowing means are controlled, and the room air temperature detected by the room air temperature detecting means during the cooling operation is controlled. When the indoor air temperature reaches the indoor air temperature set value, the evaporating temperature of the evaporating heat exchanger installed in the room is the desired dew point temperature. Down the target value Lever, the heat pump control means first throttle the expansion valve, the outlet temperature the target value or more, can be raised rapidly to a temperature below the room air temperature.

  At this time, the outlet temperature can be increased more quickly by simultaneously increasing the air volume of the blowing means. As a result, the air conditioner according to the present invention can quickly increase the piping temperature to alleviate dehumidification. That is, when the dew point temperature of the indoor air is lower than the desired dew point temperature, the air conditioner can quickly shift to high sensible heat ratio cooling with a high sensible heat ratio, and can reduce dehumidification.

  If the dew point temperature of the indoor air exceeds the desired dew point temperature, it is possible to dehumidify until the desired dew point temperature is reached, and the air conditioner brings the dew point temperature of the room air closer to the target dew point temperature. Is possible. In addition, when the heat pump control means increases the opening of the expansion valve and increases the number of rotations of the compressor, the air volume correction means increases the blown air volume, so that the cooling capacity is maintained and the rise in room temperature is suppressed. However, dehumidification can be mitigated by raising the piping temperature. That is, when the dew point temperature of indoor air is lower than the desired dew point temperature, the air conditioner can quickly dehumidify and shift to high sensible heat ratio cooling with a high sensible heat ratio.

  In addition, when the dew point temperature of indoor air is constantly kept constant, the water vapor partial pressure in the air is also constant, thus preventing the water vapor partial pressure difference from the body surface boundary layer from expanding to a substantially constant level. be able to. In particular, it is possible to prevent excessive cooling at the hands and toes with a large surface area per unit volume, and it is possible to achieve a comfortable temperature and humidity by keeping the water vapor partial pressure of the room air constant without mounting a humidity sensor.

  In the second invention, in particular, the heat pump control means of the first invention increases the opening degree of the expansion valve in the first step, and controls the opening degree of the expansion valve to be lower than that in step 1 in the second step. It can be quickly started up to a comfortable temperature and humidity.

  In the third aspect of the invention, in particular, the heat pump control means of the first aspect of the invention increases the air volume with the activation of the first step, and in the second step, the air volume is adjusted so that the indoor air temperature is within a predetermined range. It is controlled and can be started up quickly to a comfortable temperature and humidity.

  In the fourth invention, in particular, the heat pump control means according to any one of the first to third inventions maintains the rotation speed of the compressor in the first step, and the evaporation temperature is within a predetermined range in the second step. The number of rotations of the compressor is increased so as to be held at a low temperature, and it is possible to quickly start up to a comfortable temperature and humidity.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings. In the following embodiments, the present invention will be described with reference to the drawings, but the present invention is not intended to be limited to these.

(Embodiment 1)
FIG. 1 is a configuration diagram of the air-conditioning apparatus according to Embodiment 1 of the present invention, and FIG. 2 is a flowchart leading to a dehumidifying and mitigating operation of the air-conditioning apparatus.

  1 and 2, the air-conditioning apparatus according to the present embodiment is a refrigeration cycle diagram during cooling, and mainly includes an outdoor unit 3, an indoor unit 1, and a refrigerant pipe 9 that connects them. The outdoor unit 3 includes a compressor 23, an inverter 21, an expansion valve 17, a condensation heat exchanger 27, an outdoor microcomputer 19, and an outdoor fan 25. The outdoor microcomputer 19 includes a heat pump control means (not shown) according to the present invention.

  The indoor unit 1 includes an evaporation heat exchanger 7, an indoor blower 11 that is a blowing means, an indoor microcomputer 15, an indoor air temperature detection means 13, and a first pipe that detects the inlet temperature of the evaporation heat exchanger 7. The temperature detection means 5a and the 2nd piping temperature detection means 5c which detects the exit temperature of the heat exchanger 7 for evaporation are provided. The arrows of the outdoor unit 3 indicate the refrigerant flow during the cooling operation by the air-conditioning apparatus according to the present embodiment.

  The refrigerant discharged from the discharge port 23 a of the compressor 23 reaches the condensation heat exchanger 27. The refrigerant condensed by exchanging heat with outdoor air having a temperature lower than that of the refrigerant in the condensation heat exchanger 27 reaches the expansion valve 17. The refrigerant whose pressure has been reduced in the expansion valve 17 and the temperature has decreased reaches the evaporating heat exchanger 7, and the refrigerant evaporated by exchanging heat with indoor air having a temperature higher than that of the refrigerant passes through the refrigerant pipe 9 to the suction port 23 b of the compressor 23. Return.

  The indoor air temperature detection means 13 provided in the indoor unit 1 is installed on the wind of the evaporation heat exchanger 7 and detects the temperature of the intake air taken into the indoor unit 1 as the indoor air temperature. The indoor microcomputer 15 includes an indoor air temperature setting means (not shown) and a pipe temperature setting means (not shown) according to the present invention.

  The indoor air temperature setting means and the pipe temperature setting means are included in a remote controller (not shown) of the air conditioner according to the present embodiment, and the indoor air temperature setting value input by the user is, for example, 26 ° C. In the pipe temperature setting means, for example, a value of 17.6 ° C. is stored as a target value for the desired pipe temperature. The indoor microcomputer 15 stores, for example, a value of 1.0 ° C. as the tolerance ΔT between the indoor air temperature and the indoor air temperature set value.

  FIG. 2 is a flowchart showing a condition determination when the air-conditioning apparatus according to the present embodiment starts shifting to the dehumidifying relaxation operation.

  In the air conditioner according to the present embodiment, the heat pump control means included in the outdoor microcomputer 19 includes the indoor air temperature setting value (26 ° C.) output from the indoor air temperature setting means and the piping temperature setting means together with the cooling start S0. And the pipe temperature target value (17.6 ° C.) are input (S1), and the room air temperature detected by the room air temperature detecting means 13 and the first pipe temperature detecting means 5a and the second pipe temperature detecting means 5c are detected. The minimum value is input as the evaporation temperature (S3), the indoor air temperature and the indoor air temperature set value, the indoor pipe temperature and the pipe temperature target value are compared (S4), and the indoor air temperature and When the difference from the indoor air temperature set value is less than 1.0 ° C. and the indoor pipe temperature is lower than the pipe temperature target value 17.6 ° C., the dehumidifying mitigation operation (S5) is performed as the indoor blower 1 of the indoor unit 1. Correcting the flow rate of the rotational speed to increase.

  Similarly, in the dehumidifying and mitigating operation (S5), the heat pump control means first lowers the opening degree of the expansion valve 17 until the temperature of the second pipe temperature detecting means 5c reaches the highest temperature in the pipe temperature sensor group, and evaporates. The amount of refrigerant flowing into the heat exchanger 7 is decreased, thereby increasing the refrigerant overheating region in the evaporating heat exchanger 7 to increase the temperature of the evaporating heat exchanger 7, and then the second pipe temperature detecting means The opening of the expansion valve 17 is increased until 5c reaches the lowest temperature in the pipe temperature sensor group, and the compressor 23 is set so that the indoor pipe temperature approximates the pipe temperature target value of 17.6 ° C. according to the corrected air volume. Control the number of revolutions.

From the indoor air temperature of 30 ° C. and the relative humidity of 90% rh (dew point temperature of 28.2 ° C.), the cooling operation by the air conditioner according to the present embodiment is started, S0 is executed at the start of the operation, and inputs from S1 to S3 Processing is executed. At this time, immediately after the start of the cooling operation, the difference between the indoor air temperature set value of 26 ° C. and the indoor air temperature of 30 ° C. is a tolerance of 1.0 ° C. or more. Therefore, the processing is changed to S3 without changing the cooling operation. The room air temperature and the indoor pipe temperature are continuously monitored. In this state, the indoor piping temperature is allowed even if it falls below the pipe temperature target value of 17.6 ° C., the cooling operation with a relatively high latent heat ratio is executed, and the dehumidification from the indoor air also proceeds.

When the cooling operation is continued, the room temperature decreases to 27.0 ° C. or lower and the evaporation temperature is lower than 17.6 ° C., the heat pump control means indicates that the temperature of the second pipe temperature detecting means 5c is within the pipe temperature sensor group. The evaporating heat exchanger 7 is reduced by reducing the amount of refrigerant flowing into the evaporating heat exchanger 7 by lowering the opening of the expansion valve 17 until the maximum temperature becomes 17.6 ° C. or higher and lower than 26.0 ° C. The temperature of the evaporating heat exchanger 7 is quickly raised by increasing the refrigerant overheating region.
Thereafter, the second pipe temperature detecting means 5c increases the opening degree of the expansion valve 17 until the lowest temperature in the pipe temperature sensor group is reached, opens the expansion valve 17, and increases the amount of refrigerant supplied to the evaporation heat exchanger 7. . At the same time, the air volume correction means increases the rotational speed of the indoor blower 11 to increase the air volume.

  With the above operation, the increase in the indoor piping temperature can be accelerated. Thereafter, the heat pump control means controls the rotational speed of the compressor 23 to shift the piping temperature to a level not lower than 17.6 ° C. By the dehumidifying and mitigating operation of the heat pump control means and the air volume correction means, the evaporation pressure is increased, and the evaporation temperature of the evaporation heat exchanger 7 can be brought close to 17.6 ° C. At this time, the blowing temperature rises and the enthalpy difference between the room air and the blowing air becomes small. However, as a result of the dehumidifying and mitigating operation of the air volume correcting means, the air volume of the blowing air increases, so that an increase in room temperature can be suppressed.

  At this time, the room air temperature is monitored, and the air volume is controlled so that the rate of change of the room air temperature at a constant time interval becomes zero, so that the room air temperature is kept constant even after the dehumidifying operation is started. be able to. At the same time, when the dew point temperature of the indoor air is 17.6 ° C. or higher, the air conditioner according to the present embodiment continues to dehumidify, but when it falls below 17.6 ° C., it becomes sensible heat cooling and the dehumidification is stopped. The In other words, the dew point temperature of indoor air is about 17.6 ° C., the water vapor partial pressure can be maintained at 20.1 hPa at an air temperature of 26 ° C., and the water vapor partial pressure difference with the human body boundary layer is a comfortable level of about 30 hPa. Can be kept in.

  In the dehumidification mitigation operation, the cooling capacity may be insufficient for the cooling load. In this case, the dehumidification mitigation operation can be stopped by providing the tolerance “1.0 ° C.”. After the dehumidification mitigation operation is stopped, the pipe temperature is allowed again even if the pipe temperature is lower than the pipe temperature target value, and the heat pump control means lowers the opening temperature of the expansion valve 17 to lower the pipe temperature of the evaporation heat exchanger 7 and Prevent overheating.

  In the above description, the indoor air temperature set value of 26 ° C. and the piping temperature target value of 17.6 ° C. have been exemplified, but these do not limit the set values.

  The air conditioner according to the present invention can maintain a constant partial pressure of water vapor in the room air and can realize a comfortable temperature and humidity, and can be used for an air conditioner that adjusts humidity using a refrigeration cycle.

DESCRIPTION OF SYMBOLS 1 Indoor unit 3 Outdoor unit 5a 1st piping temperature detection means 5c 2nd piping temperature detection means 7 Evaporation heat exchanger 9 Refrigerant piping 11 Indoor blower (blowing means)
13 Indoor Air Temperature Detection Means 15 Indoor Microcomputer 17 Expansion Valve 19 Outdoor Microcomputer 21 Inverter 23 Compressor 25 Outdoor Blower 27 Condensation Heat Exchanger

Claims (4)

A compressor having a variable rotational speed, a heat exchanger for condensation, an expansion valve, and an evaporating heat exchanger are connected by a refrigerant pipe, and a refrigerant is circulated in the refrigerant pipe to constitute a refrigeration cycle, and the heat exchange for evaporation A blower unit that is installed on the leeward side of the chamber and sends out the air taken in through the evaporating heat exchanger into the room, and an indoor air temperature setting unit that outputs the input desired indoor air temperature as the indoor air temperature set value An indoor air temperature detecting means for detecting the indoor air temperature, a first pipe temperature detecting means for detecting the inlet temperature of the evaporating heat exchanger, and a second pipe for detecting the outlet temperature of the evaporating heat exchanger. A temperature detection unit; a pipe temperature setting unit configured to set and output a dew point temperature of air having a desired water vapor partial pressure in the room as a target value of the pipe temperature; and a heat pump control unit, and the heat pump control. The stage uses the lower one of the inlet temperature and the outlet temperature as an evaporation temperature, a difference between the indoor air temperature and the indoor air temperature set value is within a predetermined range, and the evaporation temperature is equal to or less than the target value. In this case, after the first step of increasing the outlet temperature until the outlet temperature is equal to or higher than the target value and lower than the indoor air temperature, a second step of maintaining the evaporation temperature within the predetermined range is executed. Furthermore, the air conditioner is characterized in that the opening degree of the expansion valve, the rotation speed of the compressor, and the air volume of the air blowing means are controlled. 2. The air conditioner according to claim 1, wherein the heat pump control unit performs control to increase the opening degree of the expansion valve in the first step and to lower the opening degree of the expansion valve than in step 1 in the second step. apparatus. The heat pump control means increases the air volume as the first step is activated, and controls the air volume so that the indoor air temperature is within a predetermined range in the second step. The air conditioning apparatus described. The heat pump control means maintains the rotation speed of the compressor in the first step, and increases the rotation speed of the compressor in the second step so that the evaporation temperature is maintained within a predetermined range. The air conditioning apparatus according to any one of claims 1 to 3.

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