JPH05264109A - Air conditioner - Google Patents

Abstract

PURPOSE:To remove liquid refrigerant in a delivery side high pressure pipe at a start up. CONSTITUTION:A compressor 1, motor-driven expansion valve 2, evaporator 3, and accumulator 4 are disposed in an indoor unit C. A condenser 5 is provided in an outdoor unit D. The unit D is located at a point above the unit C. A first bypass line 16 is provided in a refrigeration line 8. A first solenoid valve SV1, reheating heat exchanger 17, and capillary tube 18 are provided from a beginning end of the line 16. An opening and closing control means 34 to open the valve SV1 for one minute at the start of the compressor 1 is provided in a microcomputer 31. When high pressure gas is delivered from the compressor 1, the liquid refrigerant in a high pressure pipe 11 on the delivery side of the compressor is discharged into a low pressure line 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner,
In particular, it relates to measures for retaining liquid refrigerant in the discharge pipe.

[0002]

2. Description of the Related Art Conventionally, in an air conditioner (annual air conditioner) for cooling a computer room or the like throughout the year, for example, as disclosed in Japanese Patent Application No. 2-214201, a compressor and an expansion unit are installed in an indoor unit. A mechanism and an evaporator are provided, and a condenser is provided in the outdoor unit.

In the above-mentioned annual air conditioner, a plurality of units are installed,
One or several of them are used as backup machines for a long period of time, and the backup machines are sequentially replaced.

[0004]

However, in the above-mentioned annual air conditioner, the compressor may be disposed at a position lower than the condenser in the outdoor unit, and the refrigerant in the condenser flows back to the discharge pipe. .. In this case, the liquid refrigerant flows back from the condenser, and the gas refrigerant flows backward and is easily condensed by the low temperature air in the room to become the liquid refrigerant, and the liquid refrigerant stays in the discharge pipe. Therefore, at the time of starting, abnormal high pressure is generated due to the liquid refrigerant staying in the discharge pipe, the high-voltage switch operates, and the compressor stops immediately after starting. In particular, in the above-mentioned backup machine, since the liquid refrigerant is likely to stay in the discharge pipe because it is stopped for a long period of time, the phenomenon in which the compressor is stopped at the time of the first start was remarkable.

The present invention has been made in view of the above points, and an object thereof is to eliminate the liquid refrigerant in the high pressure pipe on the discharge side at the time of starting.

[0006]

In order to achieve the above object, the means of the invention according to claim 1 is such that the opening / closing means of the bypass passage is opened for a predetermined time by the opening / closing control means to cause the liquid in the discharge pipe to be opened. The refrigerant is released to the low pressure line.

Specifically, the means taken by the invention according to claim 1 is that the compressor (1) is as shown in FIG. 1 (solid line only).
, Condenser (5), expansion mechanism (2), and evaporator (3)
Refrigerant circuit (8) in which and are sequentially connected so that the refrigerant can circulate.
It is premised on an air conditioner equipped with.

Further, the high pressure line (10) of the discharge gas of the compressor (1) and the low pressure line (1) of the refrigerant circuit (8).
A bypass path (16) for connecting with (2) is provided.

In addition, an opening / closing means (SV1) provided on the bypass passage (16) for opening and closing the bypass passage (16)
Is provided.

Further, there is provided an opening / closing control means (34) for opening the opening / closing means (SV1) for a predetermined time when the compressor (1) is started.

Further, the means taken by the invention according to claim 2 is to open and close the opening / closing means only while the discharge pipe temperature is lower than the saturation temperature corresponding to the condensation pressure.

Specifically, the means taken by the invention according to claim 2 is, in addition to the air conditioner as the premise of the invention according to claim 1, the above-mentioned compression as shown in FIG. 2 (only the solid line). A bypass passage (16) connecting the high pressure line (10) of the discharge gas of the machine (1) and the low pressure line (12) of the refrigerant circuit (8) is provided.

Further, an opening / closing means (SV1) provided in the bypass passage (16) for opening and closing the bypass passage (16)
Is provided.

In addition, a discharge pipe temperature detecting means (Th) for detecting the discharge pipe temperature (Td) of the compressor (1) is provided.

Moreover, the saturation temperature detecting means (38) for detecting the saturation temperature (Tc) corresponding to the condensation pressure of the condenser (5).
Is provided.

Furthermore, the discharge pipe temperature (Td) of the discharge pipe temperature detecting means (Th) and the saturation temperature detecting means (3).
8) Received the signal of the saturation pressure equivalent saturation temperature (Tc) of
At the time of starting the compressor (1), the discharge pipe temperature (Td)
The opening / closing control means (34) for opening the opening / closing means (SV1) is provided only while the temperature is lower than the saturation pressure equivalent saturation temperature (Tc).

Further, the means taken by the invention according to claim 3 utilizes an existing bypass passage for reheating indoor air in order to remove the liquid refrigerant in the discharge pipe.

Specifically, the means taken by the invention of claim 3 is the same as that of the invention of claim 1 or 2.
As shown in (solid line and broken line only) and FIG. 2 (solid line and broken line only), one end of the bypass passage (16) is the discharge pipe (1).
1), the other end is disposed in the low pressure line (12) between the expansion mechanism (2) and the evaporator (3), and the bypass passage (16)
The heat exchanger (17) for reheating is provided in the above.

Further, the means taken by the invention according to claim 4 is to remove the liquid refrigerant from the discharge pipe when the outdoor unit is arranged above the indoor unit.

Specifically, the means taken by the invention according to claim 4 is that, as shown in FIGS. 1 and 2, the indoor unit (C) is the same as the invention according to claim 1, 2 or 3.
The compressor (1), the expansion mechanism (2), and the evaporator (3) are housed, and the bypass passage (16) and the opening / closing means (SV1).
) And are stored.

On the other hand, the outdoor unit (D) has a configuration in which the condenser (5) is housed. Further, the outdoor unit (D) is arranged above the indoor unit (C).

[0022]

With the above structure, in the invention according to claim 1,
The condenser (5) is attached to the discharge pipe (11) while the air conditioner is stopped.
Liquid refrigerant and gas refrigerant flow backward from the liquid refrigerant, and the liquid refrigerant stays in the discharge pipe (11) in a liquid state, while the gas refrigerant also condenses and stays as a liquid refrigerant while stopped.

On the other hand, when the opening / closing control means (34) opens the opening / closing means (SV1) for a predetermined time when the compressor (1) is started, the high pressure gas is discharged from the compressor (1). Due to the pressure difference between the high pressure line (10) and the low pressure line (12), the liquid refrigerant in the high pressure line (10) is discharged to the low pressure line (12) through the bypass passage (16), and the inside of the high pressure line (10). The high pressure of will be kept in a normal state.

Further, in the second aspect of the invention, the discharge pipe temperature detecting means (Th) detects the discharge pipe temperature of the compressor (1), while the saturation temperature detecting means (38) functions as the condenser (5). The saturation temperature (Tc) corresponding to the condensation pressure is detected. The opening / closing control means (34) receives the discharge pipe temperature (Td) and the condensation pressure equivalent saturation temperature (Tc), and when the compressor (1) is started, the discharge pipe temperature (Td) corresponds to the condensation pressure equivalent saturation temperature. The opening / closing means (SV1) is opened only while the temperature is lower than (Tc), and the high pressure line (1) is passed through the bypass line (16).
The liquid refrigerant in 0) flows out to the low pressure line (12). Therefore, the liquid refrigerant is circulated in the bypass passage (16) only when the liquid refrigerant is retained in the high-pressure line (10), and is circulated in the condenser (5) during normal operation in which the liquid refrigerant is not retained. The amount of refrigerant to be used does not decrease, and the air conditioning capacity is secured.

Further, in the invention according to claim 3, a heat exchanger (17) for reheating is arranged in the bypass passage (16), and hot gas is circulated from the high pressure line (10) in the bypass passage (16). And heat exchanger for reheating for dehumidification (17)
To heat the room air. By utilizing this existing reheat bypass path (16), the liquid refrigerant in the high pressure line (10) is made to flow into the low pressure line (12) between the expansion mechanism (2) and the evaporator (3) at startup. To the bypass (1
The liquid refrigerant in the high-pressure line (10) can be removed without newly installing 6).

In the invention according to claim 4, the outdoor unit (D) is arranged above the indoor unit (C),
When the compressor (1) is arranged in the indoor unit (C), the refrigerant flows backward from the condenser (5) in the outdoor unit (D) to the high pressure line (10) in the indoor unit (C). The liquid refrigerant flows back and stays, or the gas refrigerant flows back and is cooled by the low-temperature room air to become liquid refrigerant, and the liquid refrigerant tends to stay in the high-pressure line (10). On the other hand, by applying the invention according to claim 1, 2 or 3, the liquid refrigerant in the high pressure line (10) is transferred to the low pressure line (1).
It is discharged to 2), and the continuation of operation immediately after the start is secured.

[0027]

As described above, according to the first aspect of the invention, the opening / closing control means (34) opens the bypass passage (16) to start the high pressure line (10) when the compressor (1) is started.
It is possible to remove the liquid refrigerant inside, and at the time of starting, an abnormally high pressure such that the high-voltage switch operates will cause a high-pressure line (10).
It is possible to smoothly start the engine. In particular, when the stop period is long, a large amount of liquid refrigerant accumulated in the high pressure line (10) can be removed, and reliable restart can be achieved.

According to the second aspect of the invention, the opening / closing means (SV1) is used only while the opening / closing control means (34) has the discharge pipe temperature (Td) lower than the condensation pressure equivalent saturation temperature (Tc).
The bypass passage (16) can be opened only when the liquid refrigerant stays in the high-pressure line (10), and the condenser (5) is normally operated during normal operation when the liquid refrigerant does not stay. The amount of the circulating refrigerant does not decrease, and it is possible to prevent the air conditioning capacity from decreasing.

According to the third aspect of the invention, the liquid refrigerant is removed from the high-pressure line (10) by utilizing the existing reheating bypass passage (16), and the bypass passage (1
The liquid refrigerant in the high-pressure line (10) can be eliminated without newly installing 6), and the continuation of the operation immediately after the start can be ensured without complicating the refrigerant pipe and increasing the cost.

Further, according to the invention of claim 4, the outdoor unit (D) is arranged above the indoor unit (C), and the compressor (1) is arranged in the indoor unit (C). When the liquid refrigerant is likely to stay in (10), the liquid refrigerant in the high pressure line (10) is replaced with the low pressure line (1).
Since it is discharged to 2), in this case as well, the continuation of the operation immediately after the start can be ensured.

[0031]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 3 shows a first embodiment of the invention according to claims 1, 3 and 4. In the figure, two air conditioners (A) and (B) are provided, and each air conditioner (A),
(B) forms a separate refrigerant piping system.

Each of the air conditioners (A) and (B) is an annual air conditioner used for cooling a computer room.
The indoor unit (C) is provided with a compressor (1), an electric expansion valve (2) as an expansion mechanism, an evaporator (3), and an accumulator (4), while an outdoor unit (D). Is provided with a condenser (5), and the outdoor unit (D) is arranged above the indoor unit (C).

The compressor (1) and the condenser (5)
The electric expansion valve (2), the evaporator (3), and the accumulator (4) are sequentially connected in the refrigerant pipe (7) so that the refrigerant can circulate to form a refrigerant circuit (8).

In this refrigerant circuit (8), the starting end is a high pressure pipe (1) on the discharge side of the compressor (1) of the high pressure line (10).
1), a first bypass line (1) whose end is arranged in a low pressure line (12) between the electric expansion valve (2) and the evaporator (3).
6), the first bypass passage (16) is provided with a first solenoid valve (SV1) as opening and closing means for opening and closing the first bypass passage (16) from the starting end side, and a hot air from the compressor (1). A heat exchanger for reheating (17) that functions as a condenser for heating indoor air with gas, and a capillary tube (18) for depressurizing the liquid refrigerant condensed in the heat exchanger for reheating (17).
And are installed.

The condenser (5) and the evaporator (3) are air heat exchangers having a fan (21), and the reheat heat exchanger (17) is provided in the air passage downstream of the evaporator (3). Are arranged.

Further, a muffler (22) and a high pressure switch (HPS) for detecting the abnormal high pressure on the discharge side and stopping the compressor (1) are arranged in the high pressure pipe (11) on the discharge side. It is set up. The high pressure line (10) between the condenser (5) and the electric expansion valve (2) has a filter (24),
A second solenoid valve (SV2) is provided.

Further, the refrigerant circuit (8) is provided with a second bypass passage (28) for bypassing the electric expansion valve (2), and the second bypass passage (28) is provided with the second bypass passage (28). A third solenoid valve (SV3) for opening and closing (28) is interposed.

Further, a closing valve is provided at each of the inlet end and the outlet end of the refrigerant pipe (7) in the indoor unit (C) and the inlet end and the outlet end of the refrigerant pipe (7) in the outdoor unit (D). (29), (29), ... Are provided.

Further, the microcomputer (31) for controlling the operation of each of the above-mentioned devices has a built-in opening / closing control means (34) and pressure equalization control means (35) which are features of the present invention. The opening / closing control means (34) is configured to open the first electromagnetic valve (SV1) for one minute when the compressor (1) is started.

Further, the pressure equalizing control means (35) uses the electric expansion valve (2) which is fully closed when the refrigerant circuit is stopped.
The third solenoid valve (SV3) is opened for 3 minutes in response to the cutoff of the refrigerant flow in the above, and the electric expansion valve (2) is bypassed via the second bypass passage (28), Side high pressure line (10) and downstream low pressure line (12)
And so that the refrigerant can flow.

In FIG. 3, the air conditioner (B)
Although not shown in the figure, the microcomputer (31) performs the same control as the air conditioner (A).

The operation of the air conditioners (A) and (B) will be described. Only one of the two units is used, and one of the air conditioners (A) and (B) is always on standby as a backup machine, and the air conditioner (A),
Alternately use (B).

One air conditioner (A) in operation,
In the normal cooling operation in (B), the first solenoid valve (SV1)
To shut off the first bypass passage (16), circulate the refrigerant through the refrigerant circuit (8), decompress the refrigerant condensed in the condenser (5) by the electric expansion valve (2), and It evaporates in 3) and cools the room.

In the dehumidifying operation, the first solenoid valve (SV1) is opened to pass the hot gas through the first bypass passage (16), and the conditioned air cooled and dehumidified by the evaporator (3) is reheated. The temperature is raised in the heat exchanger (17).

When the compressor (1) is stopped, the pressure equalizing control means (35) opens the third solenoid valve (SV3) to allow the refrigerant to flow through the second bypass passage (28), and the high pressure line (10). And the low pressure line (12) are communicated with each other to equalize the pressure in the refrigerant circuit (8). This makes it possible to reduce the high and low differential pressure, an abnormal high pressure is generated in the high pressure line (10) at the time of restarting after the stop, the high pressure switch (HPS) operates, and the compressor (1) stops. A situation such as (high-voltage cut) can be prevented. Further, in order to prevent this high pressure cut, if a pressure equalizing pipe is provided between the high pressure pipe (11) on the discharge side and the low pressure line (12) between the evaporator (3) and the accumulator (4), the liquid level is reduced. However, this liquid back can be prevented by the second bypass passage (28).

On the other hand, when the compressor (1) is stopped, the refrigerant in the condenser (5) located above flows backward through the high-pressure pipe (11) on the discharge side toward the compressor (1) located below. ..
In this case, the liquid refrigerant flows backward from the condenser (5) and stays in the high-pressure pipe (11) on the discharge side, and the gas refrigerant flows backward and is condensed by the low-temperature air in the room to become the liquid refrigerant. Remains in the high pressure pipe (11). In particular, in the backup machine, the liquid refrigerant tends to stay in the high pressure pipe (11) on the discharge side during the stoppage for one month.

Therefore, the air conditioner (A) in use,
At the time of restarting after the suspension of (B), or particularly at the time of starting the backup machine, the opening / closing control means (34) opens the first solenoid valve (SV1) for a predetermined time so that the compressor (1) is removed. The high pressure gas (1
0) and the low-pressure line (12), the liquid refrigerant in the high-pressure pipe (11) on the discharge side is removed by the first bypass passage (16).
Is discharged to the low-pressure line (12) between the electric expansion valve (2) and the evaporator (3) through the high pressure pipe (11) on the discharge side and is kept in a normal state. Become.

According to this embodiment, the opening / closing control means (34)
As a result, the first bypass passage (16) can be opened to remove the liquid refrigerant in the discharge-side high-pressure pipe (11), and the high-pressure pressure switch (HPS) is activated when restarting after the stop. An abnormally high pressure does not occur in the high pressure pipe (11) on the discharge side, and smooth restart is possible. In particular, in a backup machine with a long stop period, a large amount of liquid refrigerant accumulated in the discharge-side high-pressure pipe (11) can be removed, and reliable starting can be achieved.

In addition, the existing first bypass path for reheating (1
6) is used to remove the liquid refrigerant from the high pressure pipe (11) on the discharge side, and the liquid refrigerant is removed from the high pressure pipe (11) on the discharge side without newly installing the first bypass passage (16). Therefore, it is possible to ensure the continuation of the operation immediately after the start-up without causing the refrigerant pipe (7) to be complicated and increasing the cost.

Further, the outdoor unit (D) is arranged above the indoor unit (C), the compressor (1) is arranged in the indoor unit (C), and the liquid refrigerant is supplied to the high pressure pipe (11) on the discharge side. Even when it easily stays, the high pressure pipe (1
Since the liquid refrigerant in 1) is discharged to the low pressure line (12),
It is possible to secure the continuation of the operation immediately after the start.

Next, FIG. 4 shows a second embodiment of the invention according to claim 2. In this embodiment, the opening / closing control means (34) opens the first solenoid valve (SV1) only while the discharge pipe temperature (Td) is lower than the condensation pressure equivalent saturation temperature (Tc).

Specifically, in the high-pressure pipe (11) on the discharge side, a discharge pipe temperature sensor (Th) as a discharge pipe temperature detecting means for detecting the discharge pipe temperature (Td) and a discharge gas pressure are detected. A high pressure sensor (HP) is provided.

The output signals of the sensors (Th) and (HP) are input to the microcomputer (31). The microcomputer (31) includes a high pressure sensor (H
Saturation temperature calculation means (3) for calculating the saturation temperature (Tc) corresponding to the condensation pressure of the condenser (5) based on the discharge gas pressure of P).
7) is built in, and a saturation temperature detecting means (38) is provided by a high pressure sensor (HP) and a saturation temperature calculating means (37).
Is configured.

Further, the microcomputer (31) has a built-in open / close control means (34), and the open / close control means (3
4) receives the signals of the discharge pipe temperature (Td) of the discharge pipe temperature sensor (Th) and the condensation pressure equivalent saturation temperature (Tc) of the saturation temperature detecting means (38), and when the compressor (1) is started. , The discharge pipe temperature (Td) is equal to the condensing pressure saturation temperature (T
It is configured to open the first solenoid valve (SV1) only while it is lower than c). That is, the opening / closing control means (34)
Indicates that the discharge pipe temperature (Td) is equal to the condensation pressure saturation temperature (T
When it is lower than c), it is determined that the gas refrigerant in the discharge side high pressure pipe (11) is condensed and the liquid refrigerant is retained, and the first solenoid valve (SV1) is opened to operate the first bypass passage ( 16) is opened to let the liquid refrigerant escape to the low pressure line (12), and when the discharge pipe temperature (Td) is equal to or higher than the condensation pressure equivalent saturation temperature (Tc), there is no liquid refrigerant in the discharge side high pressure pipe (11). It is configured to discriminate and close the first solenoid valve (SV1). Other configurations are similar to those of the previous embodiment.

In FIG. 4, the air conditioner (B)
Although not shown in the figure, the microcomputer (31) is controlled in the same manner as the air conditioner (A).

In this embodiment, the discharge pipe temperature sensor (Th) is used.
Detects the discharge pipe temperature (Td) of the compressor (1),
The saturation temperature detection means (38) detects the saturation temperature (Tc) corresponding to the condensation pressure of the condenser (5). The opening / closing control means (34) receives the discharge pipe temperature (Td) and the condensation pressure equivalent saturation temperature (Tc), and when the compressor (1) is started, the discharge pipe temperature (Td) corresponds to the condensation pressure equivalent saturation temperature. The first solenoid valve (SV1) is opened only while the temperature is lower than (Tc), and the liquid refrigerant in the discharge side high pressure pipe (11) flows out to the low pressure line (12) through the first bypass passage (16). To do. Therefore,
The liquid refrigerant is circulated in the bypass passage (16) only when the liquid refrigerant is retained in the high-pressure line (10), and the condenser (5) is in normal operation when the liquid refrigerant is not retained.
The amount of the refrigerant flowing through does not decrease, and the air conditioning capacity is secured.

As described above, according to this embodiment, the opening / closing control means (34) opens the first solenoid valve (SV1) only while the discharge pipe temperature (Td) is lower than the condensation pressure equivalent saturation temperature (Tc). Therefore, the first bypass passage (16) can be opened only when the liquid refrigerant is retained in the high pressure pipe (11) on the discharge side, and the amount of refrigerant flowing through the condenser (5) during normal operation is reduced. Without doing so, it is possible to prevent the air conditioning capacity from decreasing.

If it is not necessary to perform the dehumidifying operation and therefore there is no first bypass passage (16) provided with the reheat heat exchanger (17) and the capillary tube (18), the first electromagnetic The first bypass passage (16) having only the valve (SV1) is connected to the high pressure pipe (11) on the discharge side and the low pressure line (1).
You may connect between 2).

The terminal end of the first bypass path (16) is
It may be connected to a low pressure line (12) between the evaporator (3) and the accumulator (4).

In addition, the third part of the pressure equalizing control means (35)
The structure for opening the solenoid valve (SV3) may be other than the above embodiment. For example, high pressure line (1
The third solenoid valve (SV3) is opened while the differential pressure between the high pressure gas pressure in (0) and the low pressure gas pressure in the low pressure line (12) exceeds a predetermined value (1 kg / cm ² ). Alternatively, the third solenoid valve (SV3) may be opened while the discharge pipe temperature (Td) is equal to or higher than the condensation pressure equivalent saturation temperature (Tc).

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an invention according to claims 1, 3 and 4.

FIG. 2 is a block diagram showing a configuration of an invention according to claims 2, 3 and 4.

FIG. 3 is a refrigerant piping system diagram showing the configuration of the air conditioner of the first embodiment.

FIG. 4 is a refrigerant piping system diagram showing a configuration of an air conditioner of a second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor 2 Electric expansion valve (expansion mechanism) 3 Evaporator 5 Condenser 8 Refrigerant circuit 10 High pressure line 12 Low pressure line 16 First bypass passage 17 Reheat heat exchanger 34 Opening / closing control means 38 Saturation temperature detecting means C Indoor unit D Outdoor unit Th Discharge pipe temperature sensor (Discharge pipe temperature detection means)

Claims (4)

[Claims] 1. A refrigerant circuit (8) comprising a compressor (1), a condenser (5), an expansion mechanism (2), and an evaporator (3) which are connected in sequence so that refrigerant can circulate. In the air conditioner, a bypass passage (16) connecting the high pressure line (10) of the discharge gas of the compressor (1) and the low pressure line (12) of the refrigerant circuit (8), and the bypass passage (16). Is installed in the bypass passage (1
6) an air opening / closing means (SV1) for opening and closing, and an opening / closing control means (34) for opening the opening / closing means (SV1) for a predetermined time when the compressor (1) is started. Harmony device. 2. A refrigerant circuit (8) comprising a compressor (1), a condenser (5), an expansion mechanism (2), and an evaporator (3), which are connected in sequence so that refrigerant can circulate. In the air conditioner, a bypass passage (16) connecting the high pressure line (10) of the discharge gas of the compressor (1) and the low pressure line (12) of the refrigerant circuit (8), and the bypass passage (16). Is installed in the bypass passage (1
6) Opening / closing means (SV1) for opening / closing, discharge pipe temperature detecting means (Th) for detecting the discharge pipe temperature (Td) of the compressor (1), and saturation temperature equivalent to the condensation pressure of the condenser (5) Saturation temperature detecting means (38) for detecting (Tc), and discharge pipe temperature (Td) of the discharge pipe temperature detecting means (Th)
And a saturation temperature equivalent saturation temperature (Tc) of the saturation temperature detecting means (38), the discharge pipe temperature (Td) is lower than the condensation pressure equivalent saturation temperature (Tc) when the compressor (1) is started. An air conditioner comprising: an opening / closing control means (34) for opening the opening / closing means (SV1) only while the temperature is low. 3. The air conditioner according to claim 1 or 2, wherein the bypass passage (16) has a discharge pipe (11) at one end.
The other end is disposed in the low pressure line (12) between the expansion mechanism (2) and the evaporator (3), and the reheat heat exchanger (17) is provided in the bypass passage (16). An air conditioner characterized by being. 4. The air conditioner according to claim 1, 2 or 3, wherein the indoor unit (C) includes a compressor (1).
The expansion mechanism (2) and the evaporator (3) are accommodated, the bypass passage (16) and the opening / closing means (SV1) are accommodated, and the outdoor unit (D) includes a condenser (5). ) Is stored, and the outdoor unit (D) is disposed above the indoor unit (C).