WO2017203680A1

WO2017203680A1 - Cooling unit

Info

Publication number: WO2017203680A1
Application number: PCT/JP2016/065692
Authority: WO
Inventors: 英希大野; 啓三福原; 考倫松浦; 剛志水町
Original assignee: 三菱電機株式会社
Priority date: 2016-05-27
Filing date: 2016-05-27
Publication date: 2017-11-30
Also published as: JP6689376B2; CN209246477U; JPWO2017203680A1

Abstract

This cooling unit is provided with: an evaporator; a drain pan disposed below the evaporator; a heater, which is disposed below the drain pan, and which performs heating; and a cover, which covers, with the drain pan, at least a part of the heater.

Description

Cooling unit

The present invention relates to a cooling unit having a heater disposed below a drain pan.

Conventionally, a technique for removing frost attached to an evaporator is known. For example, in the prior art described in Patent Document 1, hot gas defrosting is performed to remove frost adhering to the evaporator by flowing hot gas discharged from the compressor to the evaporator (for example, patents). Reference 1).

JP-A 63-169458

However, the conventional technique as described in Patent Document 1 has a problem that frost cannot be removed efficiently. Because the air heated by exchanging heat with the hot gas flowing in the evaporator expands and becomes less dense, warm air gathers on the upper side and cold air on the lower side in the space where the evaporator is accommodated. Gather. Therefore, the heat of the air in the space in which the evaporator is accommodated cannot be efficiently used for removing frost.

The present invention has been made in view of the above-described problems, and an object thereof is to obtain a cooling unit that can efficiently perform defrosting of an evaporator.

A cooling unit according to the present invention includes at least an evaporator of a refrigerant circuit formed by connecting a compressor, a condenser, an expansion device, and an evaporator with refrigerant piping, and a drain pan disposed below the evaporator. The heater is disposed below the drain pan, and includes a heater that performs heating, and a cover that covers at least a part of the heater together with the drain pan.

According to the present invention, the drain pan heated by the heater warms the evaporator from below the evaporator, so that the evaporator can be efficiently defrosted.

It is the figure which described typically the refrigerating-cycle apparatus by which the evaporator which concerns on Embodiment 1 of this invention is arrange | positioned. It is the figure which described typically the state which looked at the cooling unit which accommodated the evaporator of FIG. 1 from diagonally. FIG. 3 is a diagram schematically showing an AA cross section of FIG. 2. It is the figure which described typically the state which looked at the drain pan and heater described in FIG. 3 from the bottom. It is the figure which described typically the state which looked at the cover of FIG. 3 from diagonally.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and the description thereof is omitted or simplified as appropriate. In addition, the shape, size, arrangement, and the like of the configuration described in each drawing can be changed as appropriate within the scope of the present invention.

[Refrigeration cycle equipment]
Embodiment 1 FIG.
FIG. 1 is a diagram schematically showing a refrigeration cycle apparatus in which an evaporator according to Embodiment 1 of the present invention is arranged. As shown in FIG. 1, the refrigeration cycle apparatus 1 includes a refrigerant circuit 2 and a hot gas path 4. A refrigerant is enclosed in the refrigeration cycle apparatus 1. The refrigerant used in the refrigeration cycle apparatus 1 of this embodiment is a refrigerant having a low global warming potential (GWP) such as R410A, R32, or CO2, for example, but includes at least one of them. It may be a refrigerant or another type of refrigerant different from these.

[Refrigerant circuit]
The refrigerant circuit 2 circulates the refrigerant, and is formed by connecting the compressor 10, the condenser 12, the expansion device 14, and the evaporator 16 through the refrigerant pipe 3. The compressor 10 compresses the refrigerant. The compressor 10 is an inverter compressor that is controlled by an inverter, for example, and can change the capacity (the amount of refrigerant sent out per unit time) by arbitrarily changing the operating frequency. The compressor 10 may be a constant speed compressor that operates at a constant operating frequency. The condenser 12 is, for example, a heat exchanger that exchanges heat between the refrigerant flowing through the condenser 12 and air, and condenses the refrigerant. For example, the condenser 12 is a fin tube type heat exchanger that includes a tube (not shown) through which a refrigerant flows and fins (not shown) attached to the tube. A blower (not shown) that blows air to the condenser 12 is disposed in the vicinity of the condenser 12. The expansion device 14 expands the refrigerant. For example, the expansion device 14 is an electronic expansion valve that can adjust the opening degree, but may be an apparatus that cannot adjust the opening degree of a capillary tube or the like.

The evaporator 16 is a heat exchanger that exchanges heat between the refrigerant flowing through the evaporator 16 and air, and evaporates the refrigerant. For example, the evaporator 16 is a fin tube type heat exchanger formed including a tube (not shown) through which a refrigerant flows and fins (not shown) attached to the tube. A blower (not shown in FIG. 1) that blows air to the evaporator 16 is disposed in the vicinity of the evaporator 16. In addition, a distributor 15 and a header 17 are connected to the evaporator 16. The distributor 15 distributes the refrigerant expanded by the expansion device 14 and flows it into the evaporator 16. The header 17 joins the refrigerant evaporated by the evaporator 16 and flowing out of the evaporator 16. A drain pan 104 that receives water dropped from the evaporator 16 is disposed below the evaporator 16.

[Operation of refrigerant circuit]
Next, the operation of the refrigerant circuit 2 will be described. The refrigerant compressed by the compressor 10 is condensed by the condenser 12. The refrigerant condensed by the condenser 12 is expanded by the expansion device 14. The refrigerant expanded by the expansion device 14 is evaporated by the evaporator 16. The refrigerant evaporated in the evaporator 16 is sucked into the compressor 10 and compressed again.

[Hot gas path]
The hot gas path 4 allows the high-temperature and high-pressure refrigerant compressed by the compressor 10 to flow to the evaporator 16. The hot gas path 4 includes a hot gas bypass pipe 6 and an on-off valve 18. The hot gas bypass pipe 6 is a pipe that bypass-connects between the discharge unit of the compressor 10 and the condenser 12 and between the expansion device 14 and the evaporator 16. For example, the hot gas bypass pipe 6 branches from between the discharge portion of the compressor 10 and the condenser 12, passes through the vicinity of the drain pan 104, and then joins between the expansion device 14 and the evaporator 16. A portion of the hot gas bypass pipe 6 passing through the vicinity of the drain pan 104 forms a heater 106 that heats the drain pan 104. A portion of the hot gas bypass pipe 6 connected between the expansion device 14 and the evaporator 16 is connected to the distributor 15. The on-off valve 18 is disposed in the hot gas bypass pipe 6 and controls the inflow of the refrigerant into the hot gas path 4 by opening and closing operation. The on-off valve 18 is, for example, an on-off switching valve that simply switches between opening and closing, but may be an electric valve that can adjust the opening. The on-off valve 18 may be provided in the hot gas bypass pipe 6 that extends from between the discharge portion of the compressor 10 and the condenser 12 and approaches the drain pan 104.

[Hot gas path operation]
If frost adheres to the evaporator 16, the efficiency of heat exchange of the evaporator 16 deteriorates. Therefore, in the example of this embodiment, hot gas refrigerant is allowed to flow through the hot gas passage 4 to heat the evaporator 16, thereby removing frost attached to the evaporator 16. That is, when the on-off valve 18 is opened, the high-temperature and high-pressure refrigerant compressed by the compressor 10 flows into the hot gas bypass pipe 6. The refrigerant flowing through the hot gas bypass pipe 6 passes through the vicinity of the drain pan 104, heats the drain pan 104, and then flows into the evaporator 16. The refrigerant flowing through the evaporator 16 heats the evaporator 16 and removes frost attached to the evaporator 16. In addition, when flowing a refrigerant into the hot gas path 4, the expansion device 14 may be closed, but the expansion device 14 may be opened.

[Cooling unit]
FIG. 2 is a diagram schematically illustrating a state where the cooling unit containing the evaporator illustrated in FIG. 1 is viewed from an oblique direction, and FIG. 3 is a diagram schematically illustrating the AA cross section of FIG. FIG. 4 is a diagram schematically illustrating a state where the drain pan and the heater illustrated in FIG. 3 are viewed from below. FIG. 5 is a diagram schematically illustrating a state where the cover illustrated in FIG. 3 is viewed obliquely. FIG. A cooling unit 100 shown in FIG. 2 is disposed inside a room and cools the room. The cooling unit 100 includes, for example, an attachment portion 103 that is attached to the ceiling of a room in which the cooling unit 100 is disposed, and is suspended from the ceiling of the room. The room in which the cooling unit 100 is disposed is, for example, a refrigeration warehouse managed at 0 degrees Celsius to minus 35 degrees Celsius.

As shown in FIG. 3, the cooling unit 100 includes a casing 102, an evaporator 16, a drain pan 104, a heater 106, a cover 108, a blower 110, a hood 112, and a damper 114. . The casing 102 is a housing that houses the evaporator 16 and the blower 110. A suction port 102 </ b> A for sucking air is formed on the rear surface of the casing 102, and a blower outlet 102 </ b> B for blowing air is formed on the front surface of the casing 102. For example, the cooling unit 100 is disposed so that the suction port 102A is closer to the wall surface than the air outlet 102B, but is disposed so that the air outlet 102B is closer to the wall surface than the suction port 102A. May be. The air sucked from the suction port 102A is cooled by the evaporator 16, and the conditioned air cooled by the evaporator 16 is blown out from the air outlet 102B. A hood 112 is attached to the suction port 102A. The hood 112 covers other than the lower part of the suction port 102A. Since the hood 112 is attached to the suction port 102A, air is sucked from below the suction port 102A. The blower outlet 102B is provided with a damper 114 that opens and closes the blower outlet 102B. The damper 114 is opened when the blower 110 is operated and blows air, and is closed when the blower 110 is stopped and blown is stopped.

The drain pan 104 is disposed below the evaporator 16 and receives water or the like dripped from the evaporator 16. The heater 106 is disposed below the drain pan 104 and performs heating. In the example of this embodiment, as shown in FIGS. 1 and 4, the heater 106 is formed including a part of the hot gas bypass pipe 6. Specifically, as shown in FIG. 4, the hot gas bypass pipe 6 includes a distribution header 160 that distributes the refrigerant and a plurality of unit channels 162 that flow the refrigerant distributed by the distribution header 160 in the middle thereof. And a merge header 164 that merges the refrigerants flowing out from the plurality of unit channels 162. The heater 106 includes a distribution header 160, a plurality of unit channels 162, and a merge header 164. In the example of this embodiment, since the heater 106 is formed including a plurality of unit flow paths 162 between the distribution header 160 and the merge header 164, the evaporator 16 can be efficiently defrosted. Can do. This is because the length of each of the plurality of unit channels 162 can be shortened and the area of the unit channel 162 in contact with the drain pan 104 can be increased by adopting a configuration having the plurality of unit channels 162. By reducing the length of the unit flow path 162, the temperature of the refrigerant that has passed through the unit flow path 162 is prevented from excessively decreasing. Frost can be performed efficiently. Furthermore, since the area of the unit flow path 162 in contact with the drain pan 104 is increased, the defrosting of the evaporator 16 performed by heating the drain pan 104 can be performed efficiently.

The unit channel 162 is attached in contact with the lower surface forming a part of the outer surface of the drain pan 104. The unit channel 162 is sandwiched between the fixed plate 166 and the lower surface of the drain pan 104 using a plurality of fixed plates 166. By adopting a configuration in which the unit channel 162 is sandwiched between the fixed plate 166 and the lower surface of the drain pan 104, the heat of the refrigerant flowing in the unit channel 162 is efficiently transmitted to the drain pan 104. Note that the fixing plate 166 is preferably formed of a material having high thermal conductivity such as metal.

2 and 3, the cover 108 covers at least a part of the heater 106 together with the drain pan 104. As shown in FIGS. 2 to 5, in the example of this embodiment, the distribution header 160, the unit channel 162, and the merge header 164 are accommodated in a space covered with the drain pan 104 and the cover 108. Since the distribution header 160, the unit flow path 162, and the merge header 164 are accommodated in the space covered with the drain pan 104 and the cover 108, the design of the cooling unit 100 is improved. Furthermore, in the example of this embodiment, since the heater 106 is covered with the drain pan 104 and the cover 108, the heater 106 can efficiently heat the drain pan 104. In addition, since the heater 106 is covered with the drain pan 104 and the cover 108, the room is prevented from being warmed by heat generated when the heater 106 is heated.

As shown in FIG. 5, the cover 108 is formed with a plurality of pairs of vent holes 180. One vent hole 180A of the pair of vent holes 180 is formed on the back surface where the suction port 102A is formed, and the other vent hole 180B of the pair of vent holes 180 is formed by the air outlet 102B. Is formed on the front. In the example of this embodiment, since at least a pair of vent holes 180 is formed in the cover 108, an air flow is generated in the space covered with the cover 108. Therefore, in the example of this embodiment, the possibility that frost adheres to the heater 106 and the like inside the space covered with the drain pan 104 and the cover 108 is reduced. Note that the number, size, position, shape, and the like of the pair of vent holes 180 are not particularly limited. In other words, at least the pair of vent holes 180 may be formed so as to be ventilated in a space covered with the drain pan 104 and the cover 108 and accommodating the heater 106. It should be noted that, as in the example of this embodiment, the structure in which the vent holes 180 are arranged in a row improves the strength of the cover 108 in which the vent holes 180 are formed, and further in the space in which the heater 106 is accommodated. Aeration is performed uniformly.

The vent hole 180 is formed below the unit channel 162. By forming the vent hole 180 below the unit flow path 162, the unit flow path 162 is difficult to be visually observed, so that the design of the cooling unit 100 can be further improved. Further, since the vent hole 180 is formed below the unit flow path 162, the air flow generated by the vent hole 180 is not easily obstructed by the unit flow path 162. Further, since the vent hole 180 is formed in the lower part of the cover 108 in the vertical direction, it is easy for cold air to be discharged to the outside of the cover 108 through the vent hole 180, and warm air is It is configured to be easily held inside. In the example of this embodiment, since warm air is easily held inside the cover 108, the drain pan 104 can be heated efficiently. Further, in the example of this embodiment, the configuration is such that cold air, in particular, cold air containing moisture is easily discharged from the vent hole 180 formed on the lower side of the cover 108 in the vertical direction. In addition, the possibility of the drain pan 104 and the like being frozen is suppressed. The vent hole 180 is formed, for example, below the center of the cover 108 in the vertical direction. Preferably, the vent hole 180 is a lower part in the vicinity of the bent portion at the lower part of the cover 108. Formed in the region.

As described above, the cooling unit 100 according to this embodiment includes the evaporator 16, the drain pan 104 disposed below the evaporator 16, and the heater that is disposed below the drain pan 104 and performs heating. 106 and a cover 108 that covers at least a part of the heater 106 together with the drain pan 104. In the cooling unit 100 of the example of this embodiment, the drain pan 104 warmed by the heater 106 warms the evaporator 16 from below the evaporator 16, so that the evaporator 16 can be defrosted efficiently. Furthermore, in the cooling unit 100 of the example of this embodiment, since at least a part of the heater 106 is covered with the drain pan 104 and the cover 108, the heater 106 can efficiently perform heating. Furthermore, in the example of this embodiment, since at least a part of the heater 106 is covered with the drain pan 104 and the cover 108, an increase in the temperature of the cooling space when the heater 106 is heated is suppressed.

For example, the heater 106 includes at least a part of the hot gas bypass pipe 6 that bypasses the refrigerant circuit 2 between the discharge unit of the compressor 10 and the condenser 12 and between the expansion device 14 and the evaporator 16. Formed. In the example of this embodiment, the heater 106 heats the evaporator 16 from below the evaporator 16, and further the refrigerant that has flowed through the hot gas bypass pipe 6 flows through the evaporator 16 to heat the evaporator 16. Therefore, the defrosting of the evaporator 16 can be performed efficiently. Furthermore, in the example of this embodiment, since the heater 106 is formed using the hot gas bypass pipe 6, the configuration of the cooling unit 100 is simplified.

Further, for example, by attaching at least a part of the hot gas bypass pipe 6 forming the heater 106 to the drain pan 104 in contact with the drain pan 104, the drain pan 104 can be efficiently heated.

Further, for example, an on-off valve 18 disposed in the hot gas bypass pipe 6 may be further provided so that the refrigerant flows through the hot gas bypass pipe 6 when the evaporator 16 is defrosted.

Further, for example, a distributor 15 that distributes the refrigerant expanded by the expansion device 14 and flows into the evaporator 16 is further provided. A portion of the hot gas bypass pipe 6 connected between the expansion device 14 and the evaporator 16 is connected to the distributor 15. By adopting a configuration in which the hot gas bypass pipe 6 is connected to the distributor 15, the connection of the hot gas bypass pipe 6 can be ensured and the connection of the hot gas bypass pipe 6 can be facilitated.

Further, for example, the heater 106 includes a distribution header 160 that distributes the refrigerant, a plurality of unit flow paths 162 that flow the refrigerant distributed by the distribution header 160, and a plurality of unit flow paths in the middle of the hot gas bypass pipe 6. And a merge header 164 that merges the refrigerant that has flowed out of 162. By forming the heater 106 including a plurality of unit flow paths 162 between the distribution header 160 and the merge header 164, the evaporator 16 can be defrosted efficiently. This is because the length of each of the plurality of unit channels 162 can be shortened and the area of the plurality of unit channels 162 in contact with the drain pan 104 can be increased by adopting a configuration having the plurality of unit channels 162. it can. By reducing the length of the unit flow path 162, the temperature of the refrigerant that has passed through the unit flow path 162 is prevented from excessively decreasing. Frost can be performed efficiently. Furthermore, since the drain pan 104 is efficiently heated by increasing the area in contact with the drain pan 104 of the plurality of unit channels 162, the defrosting of the evaporator 16 performed by heating the drain pan 104 is efficiently performed. Can do.

Further, for example, the design of the cooling unit 100 is improved by covering the distribution header 160, the plurality of unit flow paths 162, and the merge header 164 with the cover 108.

Further, for example, a casing 102 that houses at least the evaporator 16 is further provided, and at least a pair of ventilation holes 180 that ventilate the heater 106 are formed in the casing 102 or the cover 108. By forming the ventilation hole 180 that ventilates the heater 106, an air flow is generated in the space in which the heater 106 is accommodated, so that generation of frost in the space in which the heater 106 is accommodated is suppressed. In the above, an example in which the vent hole 180 is formed in the cover 108 has been described. However, when the heater 106 is disposed in a space covered with the casing 102, the drain pan 104, and the cover 108. The ventilation hole 180 may be formed in the casing 102.

Further, for example, at least a part of the heater 106 is disposed above the vent hole 180. Since at least a part of the heater 106 is disposed above the vent hole 180, the heater 106 is difficult to see through the vent hole 180, so that the design is improved. Furthermore, since the air flow generated by the vent hole 180 is not easily obstructed by the heater 106, the possibility that frost adheres to the heater 106 and the like covered with the drain pan 104 and the cover 108 is reduced. Further, at least a part of the heater 106 is disposed above the vent hole 180, so that cold air can be easily discharged to the outside of the cover 108 through the vent hole 180, and warm air is Since it becomes easy to hold | maintain inside 108, the drain pan 104 can be heated efficiently. Furthermore, since cold air, in particular, cold air containing moisture is easily discharged from the vent hole 180, the possibility that the heater 106, the drain pan 104, and the like are frozen is suppressed. For example, the portion formed above the vent hole 180 of the heater 106 is a plurality of unit flow paths 162 between the distribution header 160 and the merge header 164.

Further, for example, the cooling unit 100 further includes a suction port 102A that is formed on the back surface of the cooling unit 100 and sucks air, and an air outlet 102B that is formed on the front surface of the cooling unit 100 and blows out air. Of the pair of vent holes 180, one vent hole 180A is formed on the surface on which the suction port 102A corresponding to the back surface is formed, and the other vent hole 180B is formed on the air outlet 102B corresponding to the back surface. It is formed on the formed surface. Therefore, when the blower 110 operates and air is sucked in from the suction port 102A and air is blown out from the air outlet 102B, air flows in from the other vent hole 180B and air flows out from the one vent hole 180A. Air flow is generated. That is, when the cooling unit 100 is performing air conditioning, an air flow is easily generated in the space in which the heater 106 is disposed. For example, the above-described air flow is more easily generated by including a hood 112 that covers the upper side of the suction port 102A and sucks air from below into the suction port 102A.

In addition, for example, the cooling unit 100 further includes a damper 114 that opens and closes the air outlet 102 </ b> B. When the damper 114 is closed during the defrosting operation in which the evaporator 16 is defrosted, Defrosting can be performed efficiently.

Further, for example, the cooling unit 100 is suspended from the ceiling, and in such a case, the above-described effect becomes particularly remarkable.

Note that the cooling unit of the present invention may be one in which the cover 108 is omitted. That is, the cooling unit of the present invention includes an evaporator 16, a drain pan 104 disposed below the evaporator 16, and a heater 106 disposed below the drain pan 104 and performing heating. 106 includes at least a part of the hot gas bypass pipe 6 that bypasses the refrigerant circuit 2 between the discharge unit of the compressor 10 and the condenser 12 and between the expansion device 14 and the evaporator 16. It may be what was done. When the evaporator 16 is defrosted, the refrigerant that heated the drain pan 104 flows into the evaporator 16, so that the evaporator 16 can be defrosted efficiently.

The present invention is not limited to the above embodiment, and can be variously modified within the scope of the present invention. That is, the configuration of the above embodiment may be improved as appropriate, or at least a part of the configuration may be replaced with another configuration. Further, the configuration requirements that are not particularly limited with respect to the arrangement are not limited to the arrangement disclosed in the embodiment, and can be arranged at a position where the function can be achieved.

For example, in the above-described embodiment, the example in which the heater 106 is formed including the hot gas bypass pipe 6 has been described. However, the heater 106 is formed including other components such as a heating wire. May be.

For example, in the above-described embodiment, the example of switching the refrigerant flow to the hot gas path 4 by switching the opening and closing of the opening and closing valve 18 has been described, but the opening and closing valve 18 is omitted. You can also.

1 refrigeration cycle device, 2 refrigerant circuit, 3 refrigerant piping, 4 hot gas passage, 6 hot gas bypass piping, 10 compressor, 12 condenser, 14 expansion device, 15 distributor, 16 evaporator, 17 header, 18 on-off valve , 100 cooling unit, 102 casing, 102A inlet, 102B outlet, 103 mounting part, 104 drain pan, 106 heater, 108 cover, 110 blower, 112 hood, 114 damper, 160 distribution header, 162 unit flow path, 164 merge header 166 fixing plate, 180 vents, 180A vents, 180B vents.

Claims

At least the evaporator of a refrigerant circuit formed by connecting a compressor, a condenser, an expansion device, and an evaporator with refrigerant piping;
A drain pan disposed below the evaporator;
Disposed below the drain pan, and a heater for heating;
A cover that covers at least a portion of the heater together with the drain pan;
With
Cooling unit.
The heater includes at least a part of a hot gas bypass pipe that bypasses between the discharge unit of the compressor and the condenser and between the expansion device and the evaporator of the refrigerant circuit. Being
The cooling unit according to claim 1.
At least a part of the hot gas bypass pipe is attached to the drain pan in a state in contact with the drain pan.
The cooling unit according to claim 2.
Further comprising an on-off valve disposed in the hot gas bypass pipe,
The cooling unit according to claim 2 or 3.
A distributor for distributing the refrigerant expanded by the expansion device to flow into the evaporator;
The portion of the hot gas bypass pipe connected between the expansion device and the evaporator is connected to the distributor.
The cooling unit according to any one of claims 2 to 4.
The heater includes a distribution header that distributes the refrigerant, a plurality of unit flow paths that flow the refrigerant distributed by the distribution header, and a refrigerant that has flowed out of the plurality of unit flow paths in the middle of the hot gas bypass pipe. A merge header, and
The distribution header, the plurality of unit flow paths, and the merge header are covered with the cover,
The cooling unit according to any one of claims 2 to 5.
A casing containing at least the evaporator;
In the casing or the cover, at least a pair of ventilation holes for ventilating the heater is formed.
The cooling unit according to any one of claims 1 to 6.
At least a portion of the heater is disposed above the vent;
The cooling unit according to claim 7.
A casing containing at least the evaporator;
The casing or the cover is formed with at least a pair of ventilation holes for ventilating the heater,
The heater is disposed in the hot gas bypass pipe, and distributes a refrigerant, a plurality of unit flow paths for distributing the refrigerant distributed in the distribution header, and a refrigerant flowing out of the plurality of unit flow paths. A merging header for merging, and
At least one of the unit channels is formed above the vent hole;
The cooling unit according to any one of claims 2 to 5.
A suction port that is formed in the back surface and sucks air; and a blowout port that is formed in the front surface and blows out air;
One of the pair of vent holes is formed on a surface corresponding to the back surface, and the other is formed on a surface corresponding to the front surface.
The cooling unit according to any one of claims 7 to 9.
The hood is attached to a surface corresponding to the back surface, covers an upper portion of the suction port, and further has a hood for sucking air from below into the suction port.
The cooling unit according to claim 10.
A damper attached to a surface corresponding to the front surface and further opening and closing the air outlet,
The cooling unit according to claim 10 or 11.
During the defrosting operation for defrosting the evaporator, the damper is in a closed state.
The cooling unit according to claim 12.
Suspended from the ceiling,
The cooling unit according to any one of claims 1 to 13.
At least the evaporator of a refrigerant circuit formed by connecting a compressor, a condenser, an expansion device, and an evaporator with refrigerant piping;
A drain pan disposed below the evaporator;
Disposed below the drain pan, and a heater for heating;
With
The heater includes at least a part of a hot gas bypass pipe that bypasses between the discharge unit of the compressor and the condenser and between the expansion device and the evaporator of the refrigerant circuit. Being
Cooling unit.