JP2010032104A - Air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent increase of pressure loss and degradation of heat exchanging performance in a heat exchange passage of a heat exchanger, and to improve cooling performance of an air conditioner. <P>SOLUTION: In this air conditioner composed of an indoor unit installed in an air-conditioned room, and an outdoor unit installed outdoors, a flow rate adjustment valve is disposed on a bypass circuit connecting a gas-liquid separator disposed on the way of an indoor heat exchange passage and an outlet of the indoor heat exchanger, temperature sensors are respectively disposed near the outlet of the indoor heat exchanger and at a suction side of a compressor, and the bypass flow rate of the refrigerant is adjusted to be optimum to improve performance. By applying this constitution, the cooling performance of the air conditioner can be improved. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an air conditioner that prevents an increase in pressure loss and a decrease in heat exchange performance in a heat exchange path of a heat exchanger.

In recent years, in response to serious environmental problems such as global warming, CO ₂ reduction is required from the viewpoint of protecting the global environment. Even in air conditioners that occupy a large weight in the energy consumption of ordinary households, energy saving is a major issue, and the demand for higher performance is very high. Therefore, research and development for improving the performance of various air conditioners has been made so far. Against such a background, we aim to improve the overall performance of air conditioners by appropriately and effectively arranging gas-liquid separators for separating the gas phase and liquid phase of the refrigerant in the refrigeration cycle. It was used as a guide for the present invention. As an invention of an air conditioner using this gas-liquid separator, a gas-liquid separator that gas-liquid separates the refrigerant is installed in the middle of the heat exchange path of the heat exchanger that functions as an evaporator, and further the gas-liquid separation By installing a bypass pipe that allows the gas-phase refrigerant separated by the evaporator to flow into the conduit connecting the outlet of the heat exchanger that functions as an evaporator and the four-way valve, the performance of the evaporator is improved. (For example, refer to Patent Document 1). According to Patent Document 1, among the heat exchangers functioning as an evaporator, the gas-liquid mixed state of the refrigerant that has been in a gas-liquid mixed state by heat exchange upstream of the gas-liquid separator is once removed by the gas-liquid separator. Since heat is exchanged in the heat exchanger on the downstream side with a large amount of liquid phase, the flow rate of the refrigerant in the pipe does not become high, and the increase in pressure loss is suppressed, leading to improved performance as an evaporator. It is said. In addition, when the evaporator is used as a condenser, a check valve is provided in the bypass pipe so that the refrigerant does not flow back through the bypass pipe and return to the gas-liquid separator.

JP 2002-372323 A

  In the refrigeration cycle described above, a check valve is installed to prevent liquid return to the gas-liquid separator. However, in the point that the valve can only be opened and closed, a contrivance is made when the refrigerant circulation amount or refrigerant state changes. However, depending on the operating conditions, when bypassing with liquid gas mixing, or when the amount of gas bypass cannot be secured sufficiently, and when the flow is divided into each refrigerant flow path, an unbalance of the flow dividing ratio occurs, and the performance is reduced. It can get worse.

  The invention of claim 1 includes an outdoor unit including a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve, an outdoor air blower, etc., an indoor heat exchanger, an indoor air blower, a dehumidifying valve used during dehumidifying operation, and the like. An indoor unit comprising: an indoor heat exchanger of the indoor unit; and a connection pipe that circulates a refrigerant to an interior of the outdoor unit that reaches the expansion valve. The indoor heat exchanger and the outdoor unit Each of the connection pipes is connected to form a refrigerant pipe path, and the refrigerant is circulated inside the air conditioner capable of performing a cooling operation or a heating operation. During the cooling operation, the heat exchange path of the indoor heat exchanger A bypass pipe that arranges a gas-liquid separator that separates the refrigerant in the middle on the downstream side of the dehumidification valve, and causes the gas-phase refrigerant separated by the gas-liquid separator to flow into the outlet pipe of the indoor heat exchanger The flow adjustment valve is installed in the bypass pipe, Outlet conduit near the serial indoor heat exchanger, and the compressor suction side, the air conditioner being characterized in that each provided a coolant temperature sensor suction heat exchange refrigerant temperature sensor and compressor.

  According to a second aspect of the present invention, in the first aspect, when gas-liquid separation is applied in the flow direction of the refrigerant during the cooling operation, the heat obtained by the heat exchange refrigerant temperature detection sensor and the compressor suction refrigerant temperature detection sensor. The throttle of the flow rate adjusting valve is adjusted so that the refrigerant temperature and the compressor suction refrigerant temperature satisfy “heat exchange refrigerant temperature <compressor suction refrigerant temperature”.

When the gas-liquid separation is applied in the flow direction of the refrigerant during the cooling operation, the pipe connected to the gas-liquid separator is (the cross-sectional area of the inflow pipe) ≈ (Cross sectional area of gas refrigerant outflow pipe) + (Cross sectional area of liquid refrigerant outflow pipe)
(Cross sectional area of gas refrigerant outflow pipe) <(Cross sectional area of liquid refrigerant outflow pipe)
It has the gas-liquid separator which satisfy | fills these conditions.

  A fourth aspect of the present invention provides the indoor heat exchanger according to any one of the first to third aspects, wherein the indoor heat exchanger is positioned on the downstream side of the gas-liquid separator according to a wind speed distribution from the indoor blower. The length of each heat exchange pipe L of the exchanger is set as “L1 at a position where the wind speed is large <L2 where the wind speed is small”.

  A fifth aspect of the present invention provides the indoor heat exchanger according to any one of the first to third aspects, wherein the indoor heat exchanger is positioned on the downstream side of the gas-liquid separator according to a wind speed distribution from the indoor blower. The thickness D of each refrigerant passage pipe of the exchanger is set as “D1 at a position where the wind speed is low <D2 where the wind speed is high”.

  A sixth aspect of the present invention is characterized in that, in any of the first to fifth aspects, the gas-liquid separator has a cylindrical shape and an inner diameter of 35 mm or more.

  The effect of claim 1 according to the present invention is used at the time of an outdoor unit including a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve, an outdoor fan, and the like, an indoor heat exchanger, an indoor fan, and a dehumidifying operation. An indoor unit including a dehumidification valve, the indoor heat exchanger of the indoor unit, and a connection pipe that circulates a refrigerant to the inside of the outdoor unit leading to the expansion valve, and the indoor heat exchanger; In the air conditioner that connects the outdoor unit and the connection pipe to form a refrigerant pipe path, circulates the refrigerant inside, and can perform a cooling operation or a heating operation, during the cooling operation, the indoor heat exchanger A gas-phase refrigerant separated from the gas-liquid separator by arranging a gas-liquid separator for separating the refrigerant in the middle of the heat exchange path downstream of the dehumidification valve provided in the middle path of the indoor heat exchanger. Bypass piping for allowing the air to flow into the outlet line of the indoor heat exchanger The bypass pipe is provided with a flow control valve, and a heat exchanger temperature detection sensor and a compressor suction refrigerant temperature detection sensor are provided in the vicinity of the outlet pipe of the indoor heat exchanger and on the compressor suction side, respectively. By using the air conditioner characterized in that, after passing through the dehumidifying valve, the gas-liquid separator installed on the downstream side of the refrigerant of the dehumidifying valve separates the liquid refrigerant from the gas refrigerant and bypasses the gas refrigerant. Therefore, the gas component that hardly contributes to the heat exchange performance as an evaporator can be bypassed, the performance as the evaporator can be improved, and the liquid refrigerant after gas-liquid separation is distributed, It is possible to eliminate the imbalance in refrigerant distribution when the liquid is mixed into the plurality of flow paths in the liquid mixed refrigerant state.

  In addition, regarding the heat exchange refrigerant temperature and the compressor suction refrigerant temperature detected by the temperature sensors provided in the vicinity of the outlet pipe of the indoor heat exchanger and on the compressor suction side, during normal cooling operation, In the path from the outlet pipe of the indoor heat exchanger to the compressor suction port, the refrigerant temperature rises by the amount of superheating, so the relationship of “heat exchange refrigerant temperature <compressor suction refrigerant temperature” is maintained. , If a phenomenon such as “the amount of super heat is extremely reduced” or “the heat exchange refrigerant temperature becomes higher than the compressor suction refrigerant temperature” occurs, “heat exchange refrigerant temperature ≧ compressor suction refrigerant temperature” Therefore, it can be determined that “the liquid refrigerant has started to be mixed into the bypass pipe”, so that the liquid refrigerant can be prevented from being mixed into the bypass pipe by restricting the flow rate adjusting valve.

  According to a second aspect of the present invention, in the air conditioner according to the first aspect, when the gas-liquid separation is applied in the refrigerant flow direction during the cooling operation, the heat exchanger temperature detection sensor and the compressor Control was made to adjust the throttle of the flow rate adjusting valve so that the heat exchange refrigerant temperature and the compressor suction refrigerant temperature obtained by the suction refrigerant temperature detection sensor are “heat exchange refrigerant temperature <compressor suction refrigerant temperature”. With this feature, the cooling performance can be improved by appropriately adjusting the amount of refrigerant passing through the bypass pipe.

The effect of claim 3 according to the present invention is that, in the air conditioner of claim 1 or 2, when gas-liquid separation is applied in the refrigerant flow direction during cooling operation, a pipe connected to the gas-liquid separator is provided. (Cross sectional area of inflow piping) ≒ (Cross sectional area of gas refrigerant outflow piping) + (Cross sectional area of liquid refrigerant outflow piping)
(Cross sectional area of gas refrigerant outflow pipe) <(Cross sectional area of liquid refrigerant outflow pipe)
By having the gas-liquid separator that satisfies the above condition, the refrigerant flowing in the two-phase flow can be easily separated into the gas refrigerant and the liquid refrigerant, and the performance as a heat exchanger can be promoted.

  The effect of claim 4 according to the present invention is that, in the air conditioner according to any one of claims 1 to 3, the indoor air blower is provided for the indoor heat exchanger located downstream of the gas-liquid separator. The length of each heat exchange pipe L of the indoor heat exchanger is set such that “L1 at a position where the wind speed is large <L2 where the wind speed is small” according to the wind speed distribution from By increasing the length of the heat exchange pipe in the section where the wind speed is low, that is, the heat transfer performance is low, and shortening the length of the heat exchange pipe in the section where the wind speed is high, that is, the heat transfer performance is high. The overall heat transfer balance can be secured satisfactorily.

  The effect of claim 5 according to the present invention is the air conditioner according to any one of claims 1 to 3, wherein the indoor air exchanger is located on the downstream side of the gas-liquid separator. The thickness D of each refrigerant flow pipe of the indoor heat exchanger is set so that “D1 at a position where the wind speed is low <D2 where the wind speed is high” according to the wind speed distribution from By reducing the thickness of the refrigerant flow pipe in the section where the wind speed is low, that is, the heat transfer performance is low, and increasing the refrigerant flow pipe in the section where the wind speed is high, that is, the heat transfer performance is high. The overall heat transfer balance can be secured satisfactorily.

  According to the sixth aspect of the present invention, in the air conditioner according to any one of the first to fifth aspects, the gas-liquid separator has a cylindrical shape, and at least its inner diameter is set to about 35 mm or more. As a result, the separation performance when the refrigerant flowing into the gas-liquid separator in the gas-liquid two-phase flow is separated into the gas refrigerant and the liquid refrigerant can be improved, and the performance of the air conditioner having the gas-liquid separator is improved. Can be made.

  An outdoor unit comprising a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve, an outdoor air blower, etc., an indoor heat exchanger, an indoor air blower, an indoor unit comprising a dehumidifying valve used during dehumidification operation, and the like, The indoor heat exchanger of the indoor unit and a connection pipe that circulates refrigerant through the interior of the outdoor unit that reaches the expansion valve are connected to the indoor heat exchanger, the outdoor unit, and the connection pipe, respectively. In an air conditioner that configures a refrigerant piping path, circulates the refrigerant inside, and can perform cooling operation or heating operation, during the cooling operation, the refrigerant in the middle of the heat exchange path of the indoor heat exchanger is separated into gas and liquid The gas-liquid separator is disposed downstream of the dehumidifying valve provided in the middle path of the indoor heat exchanger, and the gas-phase refrigerant separated by the gas-liquid separator is supplied to the outlet pipe of the indoor heat exchanger. A bypass pipe to be introduced is arranged, and the bypass pipe has a flow rate. An air conditioner characterized in that a valve is provided and a heat exchanger refrigerant temperature detection sensor and a compressor suction refrigerant temperature detection sensor are provided in the vicinity of the outlet pipe of the indoor heat exchanger and on the compressor suction side, respectively. Thus, after passing through the dehumidifying valve, the gas-liquid separator installed on the downstream side of the refrigerant of the dehumidifying valve separates the liquid refrigerant and the gas refrigerant, and bypasses the gas refrigerant, so that the heat exchange performance as an evaporator When the liquid refrigerant after gas-liquid separation is distributed, the gas component that hardly contributes to the gas can be bypassed and the performance as an evaporator can be improved. It is possible to eliminate the imbalance in refrigerant distribution when the flow is divided.

  In addition, regarding the heat exchange refrigerant temperature and the compressor suction refrigerant temperature detected by the temperature sensors provided in the vicinity of the outlet pipe of the indoor heat exchanger and on the compressor suction side, during normal cooling operation, In the path from the outlet pipe of the indoor heat exchanger to the compressor suction port, the refrigerant temperature rises by the amount of superheating, so the relationship of “heat exchange refrigerant temperature <compressor suction refrigerant temperature” is maintained. , If a phenomenon such as “the amount of super heat is extremely reduced” or “the heat exchange refrigerant temperature becomes higher than the compressor suction refrigerant temperature” occurs, “heat exchange refrigerant temperature ≧ compressor suction refrigerant temperature” Therefore, it can be determined that “the liquid refrigerant has started to be mixed into the bypass pipe”, so that the liquid refrigerant can be prevented from being mixed into the bypass pipe by restricting the flow rate adjusting valve.

  The refrigeration cycle which mounts the gas-liquid separator and flow control valve which were described in Claim 1 about the air conditioner comprised by the indoor unit installed in the air-conditioning room | chamber interior which concerns on this invention, and the outdoor unit installed outdoors is a figure. It is shown in 1. The refrigerant flow during the cooling operation will be described with reference to FIG. 1. The high-temperature and high-pressure gas-phase refrigerant compressed by the compressor 1 flows into the outdoor heat exchanger 3 through the four-way valve 2. Then, the outdoor fan 4 exchanges heat between the outdoor air and the refrigerant flowing in the outdoor heat exchanger 3, whereby the refrigerant is condensed and flows into the expansion valve 5 as a high-temperature and high-pressure liquid-phase refrigerant.

  In the expansion valve 5, the refrigerant is depressurized to a low temperature / low pressure and flows into the indoor heat exchanger 6. In FIG. 1, during the cooling operation, the indoor heat exchange path located on the upstream side with respect to the gas-liquid separator 11 installed in the indoor heat exchanger 6 is located on the first indoor heat exchanger 9 and on the downstream side. The indoor heat exchange path is distinguished from the second indoor heat exchanger 10. First, the refrigerant flowing into the first indoor heat exchanger 9 exchanges heat with indoor air by the indoor fan 7, the indoor air is cooled, and the refrigerant evaporates. Thereafter, the gas-liquid mixed refrigerant that has passed through the dehumidifying valve 8 used during the dehumidifying operation once flows into the gas-liquid separator 11, and the vapor-phase refrigerant separated here passes through the bypass circuit 14 to the outlet pipe 12. Flowing. At this time, the refrigerant bypass amount appropriate for the entire cycle can be adjusted by adjusting the throttle of the flow rate adjusting valve 13 installed on the bypass circuit. On the other hand, the refrigerant for the liquid phase separated by the gas-liquid separator 11 flows into the second indoor heat exchanger 10 as usual, where it exchanges heat with the room air again, cools the room air, and evaporates. . The gas-phase refrigerant that has passed through the bypass circuit 14 joins at the outlet pipe 12 and is returned to the compressor 1 through the four-way valve 2 to be made high-temperature / high-pressure refrigerant again. By repeating this cycle, the air conditioner is cooled. Also, during the heating operation, the direction of the refrigerant flow is switched by the four-way valve 2 so that the roles of the indoor heat exchanger 6 and the outdoor heat exchanger 3 are reversed, the outdoor heat exchanger 3 becomes an evaporator, and the indoor heat The exchanger 6 serves as a condenser. At that time, the flow rate adjusting valve 13 installed on the bypass circuit 14 is closed to prevent the refrigerant flowing into the second indoor heat exchanger 10 from flowing into the bypass circuit 14. Can do. As a specific effect, during the cooling operation, the refrigerant that has become a gas-liquid mixed state by heat exchange in the first indoor heat exchanger 9 is temporarily removed of the gas phase by the gas-liquid separator, and has a large liquid phase content Since heat is exchanged in the heat exchanger on the downstream side, the flow rate of the refrigerant in the pipe is not increased as a whole, and an increase in pressure loss is suppressed, and heat is exchanged using a refrigerant having a high liquid phase ratio. This also leads to an improvement in overall heat transfer performance. Other effects include optimization of the path balance of the refrigerant that is diverted in the second indoor heat exchanger 10. These effects are higher when the cooling capacity is larger.

  FIG. 2 shows an example of an indoor refrigeration cycle in which the gas-liquid separator and the flow rate adjustment valve according to claim 1 are mounted. The refrigerant flow during the cooling operation will be described with reference to FIG. 2. The refrigerant that has flowed in from the upper part of the figure flows into the first indoor heat exchanger 9, exchanges heat, passes through the dehumidification valve 8, and then passes through the dehumidification valve 8. It flows into the liquid separator 11. The gas phase refrigerant separated by the gas-liquid separator 11 passes through the bypass circuit 14 whose flow rate is adjusted by the flow rate adjusting valve 13 and then reaches the outlet pipe 12. On the other hand, the refrigerant of the liquid phase separated by the gas-liquid separator 11 flows into the second indoor heat exchanger 10 as usual, passes through the heat exchange, and then flows in from the bypass circuit 14 in the outlet pipe 12. It merges with the refrigerant and flows out to the outdoor unit side.

  In the process of opening the throttle of the flow rate adjustment valve 13, when the superheat amount obtained from the temperature difference between the indoor heat exchanger temperature sensor 15 and the compressor suction temperature sensor 20 suddenly drops, liquid refrigerant is supplied to the bypass circuit 14. Since it can be determined that the refrigerant has started to flow in, the bypass of the liquid refrigerant can be prevented by narrowing the throttle of the flow rate adjustment valve 13 to the point where the amount of superheat when the cycle is stable can be obtained.

  A specific example of the control described in claim 2 will be described with reference to FIG. First, after the cooling operation of the air conditioner is started, after the cycle is stabilized and the opening degree of the expansion valve 5 is kept constant, the throttle of the flow rate adjustment valve 13 that has been fully closed until then is gradually opened to separate the gas and liquid. The gas refrigerant separated by the vessel 11 is bypassed to the outlet pipe 12 through the bypass circuit 14. By opening the throttle of the flow rate adjustment valve 13 as much as possible while monitoring the super heat amount at the time of cycle stabilization with both the indoor heat exchanger temperature sensor 15 and the compressor suction temperature sensor 20, It can be adjusted to the optimum bypass amount of the gas refrigerant, and the cooling performance can be improved.

FIG. 3 shows the gas-liquid separator 11 when gas-liquid separation is applied (cross-sectional area of the inflow pipe 18) ≈ (cross-sectional area of the gas refrigerant outflow pipe 19a) + (cross-sectional area of the liquid refrigerant outflow pipe 19)
(Cross sectional area of gas refrigerant outflow pipe 19a) <(Cross sectional area of liquid refrigerant outflow pipe 19)
When the flow rate adjustment valve 13 optimizes the outflow rate of the gas refrigerant, the refrigerant flowing out from the refrigerant pipe 19 can be substantially liquid refrigerant, and the performance as an evaporator can be improved. it can. For example, when the diameter of the inflow pipe 18 is φ9.52, the above condition can be satisfied by setting the liquid refrigerant outflow pipe 19 to φ7 and the gas refrigerant pipe 19a to φ6.35.

  In the air conditioner taken up in the first embodiment, the length of the refrigerant channel pipe of the second indoor heat exchanger 10 located on the downstream side of the gas-liquid separator 11 according to the wind speed distribution 16 from the indoor fan 7 is set. The adjustment is shown in FIG. Normally, since a gas-liquid mixed phase refrigerant flows in, it is necessary to use an expensive flow divider with a high flow-dividing performance for the diversion immediately before the heat exchanger. The liquid single-phase refrigerant flows in by passing through the vessel, and a very stable diversion can be realized. Therefore, it is possible to set the refrigerant flow path arrangement according to the heat exchange amount. That is, as shown in FIG. 4, a short refrigerant flow path such as the refrigerant flow path B and the refrigerant flow path C is installed at a position where the wind speed is relatively fast and the heat transfer performance is high, and conversely the wind speed is relatively slow, By installing long refrigerant flow paths such as the refrigerant flow path A and the refrigerant flow path D at positions where the performance is low, the overall heat exchanger performance is improved.

  In the air conditioner taken up in the first embodiment, the second indoor heat exchanger 10 and the second indoor heat exchanger 10 located on the downstream side of the gas-liquid separator 11 according to the wind speed distribution 16 from the indoor fan 7. FIG. 5 shows an adjustment of the thickness of the connecting pipe 17 that connects the branch pipe provided before the inflow. Normally, since a gas-liquid mixed phase refrigerant flows in, it is necessary to use an expensive flow divider with a high flow-dividing performance for the diversion immediately before the heat exchanger. The liquid single-phase refrigerant flows in by passing through the vessel, and a very stable diversion can be realized. Therefore, it is possible to set the refrigerant flow path arrangement according to the heat exchange amount. That is, as shown in FIG. 5, the refrigerant pipe B and the refrigerant pipe C connected to the refrigerant flow path B and the refrigerant flow path C located at a place where the wind speed is relatively high and the heat transfer performance is high employ a thick refrigerant pipe as compared with others. Thus, it becomes possible to allow more refrigerant to flow into the section where the wind speed is fast and the heat transfer performance is good, and the overall heat transfer performance of the heat exchanger is improved.

  FIG. 6 shows the experimental results showing the relationship between the inner diameter and the performance (COP improvement ratio) of the gas-liquid separator 11 according to the present invention. In this experiment, the result of measuring the performance with the inner diameter of the gas-liquid separator as a parameter is shown. From the result of this experiment, the inner diameter of the gas-liquid separator 11 is set to approximately 35 mm or more to improve the performance. Can do. Further, since the performance is converged when the gas-liquid separator 11 has an inner diameter of about φ48 mm, the diameter D of the gas-liquid separator 11 is set to φ35 mm ≦ D ≦ φ48 mm without increasing the inner diameter more than necessary. Improvements can be made.

It is a refrigeration cycle whole figure concerning the air harmony machine of the present invention. (Examples 1 and 2) It is an Example which concerns on the air conditioner of this invention. (Example 1) It is an Example which concerns on the air conditioner of this invention. (Example 3) It is an Example which concerns on the air conditioner of this invention. Example 4 It is an Example which concerns on the air conditioner of this invention. (Example 5) It is an Example which concerns on the air conditioner of this invention. (Example 6)

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Compressor 2 Four-way valve 3 Outdoor heat exchanger 4 Outdoor ventilation fan 5 Expansion valve 6 Indoor heat exchanger 7 Indoor ventilation fan 8 Dehumidification valve 9 1st indoor heat exchanger 10 2nd indoor heat exchanger 11 Gas-liquid separator 12 Outlet pipe 13 (for indoor heat exchanger) Flow rate adjusting valve 14 Bypass circuit 15 Indoor heat exchanger temperature sensor 16 Wind speed distribution 17 (from indoor fan) Connection pipe 18 (for indoor heat exchanger) Inflow pipe 19 Liquid refrigerant outflow pipe 19a Gas bypass outlet pipe 20 Compressor suction temperature sensor

Claims (6)

An outdoor unit including a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve, and an outdoor air blowing device, an indoor heat exchanger, an indoor air blowing device, an indoor unit including a dehumidifying valve used during dehumidifying operation, and the indoor unit It is comprised by the connection piping which circulates a refrigerant | coolant inside the indoor heat exchanger and the said expansion valve provided in the said outdoor unit, The refrigerant | coolant is connected by connecting the said indoor heat exchanger, the said outdoor unit, and the said connection piping, respectively. In an air conditioner that configures a piping path and performs cooling operation and heating operation by circulating the refrigerant inside the refrigerant piping path,
During cooling operation, a gas-liquid separator is arranged in the middle of the heat exchange path of the indoor heat exchanger, and is arranged downstream of the dehumidification valve provided in the middle path of the indoor heat exchanger,
Arranging bypass piping to bypass the outlet piping from the gas-liquid separator,
Install a flow control valve in the bypass piping path,
An air conditioner characterized in that a heat exchange refrigerant temperature detection sensor and a compressor suction refrigerant temperature detection sensor are provided in the vicinity of the outlet pipe of the indoor heat exchanger and on the compressor suction side, respectively. 2. The heat exchange refrigerant temperature and compressor obtained by the heat exchange refrigerant temperature detection sensor and the compressor suction refrigerant temperature detection sensor when gas-liquid separation is applied in the refrigerant flow direction during cooling operation according to claim 1. The suction refrigerant temperature is
An air conditioner characterized by adjusting a throttle of the flow rate adjusting valve so that a heat exchange refrigerant temperature <a compressor suction refrigerant temperature. In claim 1 or 2, when gas-liquid separation is applied in the refrigerant flow direction during cooling operation, the pipe connected to the gas-liquid separator is (cross-sectional area of the inflow pipe) ≈ (disconnection of the gas refrigerant outflow pipe) (Area) + (Cross sectional area of liquid refrigerant outflow piping)
(Cross sectional area of gas refrigerant outflow pipe) <(Cross sectional area of liquid refrigerant outflow pipe)
An air conditioner comprising a gas-liquid separator that satisfies the following conditions. 4. The heat exchange pipe of the indoor heat exchanger according to claim 1, wherein the indoor heat exchanger located on the downstream side of the gas-liquid separator is in accordance with a wind speed distribution from the indoor blower. The length of L,
L1 where wind speed is large <L2 where wind speed is small
An air conditioner characterized in that 4. The refrigerant flow path of the indoor heat exchanger according to claim 1, wherein the indoor heat exchanger located on the downstream side of the gas-liquid separator has each refrigerant flow path of the indoor heat exchanger according to a wind speed distribution from the indoor air blower. The thickness D of the pipe
D1 where the wind speed is small <D2 where the wind speed is large
An air conditioner characterized in that   6. The air conditioner according to claim 1, wherein the gas-liquid separator has a cylindrical shape, and an inner diameter thereof is set to 35 mm or more.

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