Chilling unit and air conditioning device

Abstract

This chilling unit comprises: a housing inside which a mechanical chamber is formed; an air heat exchanger which is provided to an upper part of the housing and which forms a blower chamber; and a fan which is provided to an upper part of the air heat exchanger and which discharges air from the blower chamber to the outside. The mechanical chamber is provided with a DCL box which has a DC reactor and a DCL cooling fan that cools the DC reactor, and a control box which has a control device that controls the DCL cooling fan. The DCL cooling fan is provided in such a manner that, during operation of the DCL cooling fan, air flow generated by the DCL cooling fan does not pass through the inside of the control box.

Description

Chilling unit and air conditioning device

[0001] The present disclosure relates to a chilling unit and an air conditioning apparatus.

[0002] Conventionally, there is an air conditioner that includes an air conditioner having an outdoor unit and an indoor unit and conditions the air of a space to be air-conditioned using a refrigerant (see, for example, Patent Document 1). The air conditioner of Patent Document 1 uses a slightly flammable refrigerant among flammable refrigerants. The air conditioner of Patent Document 1 also includes a controller that controls the outdoor unit and the indoor unit. This controller is provided in a control box that houses electronic components such as a DC reactor. The electronic components housed in the control box are cooled by an indoor fan of the indoor unit. In addition, in the event of a refrigerant leak, the indoor fan is operated to diffuse the leaked refrigerant into the space to be air-conditioned.

[0003] Japanese Patent Application Laid-Open No. 2022-39608

[0004] In recent years, there has been a demand for higher performance air conditioners, which has led to increased capacity and heat generation, particularly in DC reactors. However, in conventional air conditioners, the indoor fan's cooling capacity is insufficient, causing the DC reactor to overheat and exceed its rated value. Furthermore, if a flammable refrigerant leaks and accumulates near the control box, which is an ignition source, there is a risk of ignition. However, conventional air conditioners do not describe a configuration for keeping the flammable refrigerant away from the control box in the event of a leak.

[0005] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a chilling unit and air conditioning apparatus that can prevent the DC reactor from rising too high in temperature, while keeping the refrigerant away from the control box, where there may be an ignition source, in the event of a refrigerant leak.

[0006] The chilling unit of the present disclosure comprises a housing having a machine chamber formed therein, an air heat exchanger provided on top of the housing and forming a blower chamber, and a fan provided on top of the air heat exchanger and discharging air from the blower chamber to the outside, the machine chamber comprising a DCL box having a DC reactor and a DCL cooling fan for cooling the DC reactor, and a control box having a control device for controlling the DCL cooling fan, the DCL cooling fan being provided so that when the DCL cooling fan is operating, the air flow generated by the DCL cooling fan does not pass through the control box.

[0007] An air conditioning apparatus according to the present disclosure includes the above-described chilling unit.

[0008] The chilling unit and air conditioner according to the present disclosure can prevent the DC reactor from rising too high in temperature, and can keep the refrigerant away from the control box, where there may be an ignition source, in the event of a refrigerant leak.

[0009] FIG. 4 is a perspective view showing the appearance of a chilling unit according to embodiment 1. FIG. 5 is a diagram showing the configuration of an air conditioning apparatus centered around the chilling unit according to embodiment 1. FIG. 6 is a perspective view showing the housing of the chilling unit according to embodiment 1. FIG. 7 is a partial enlarged view of the housing shown in FIG. 3. FIG. 8 is a diagram showing a part of the internal configuration of the housing shown in FIG. 3. FIG. 9 is a schematic diagram explaining the arrangement of devices in the machine room of the chilling unit according to embodiment 1. FIG. 10 is a perspective view of the refrigerant circuit side control box of the chilling unit according to embodiment 1, seen from the rear side. FIG. 11 is a perspective view showing the DCL box of the chilling unit according to embodiment 1. FIG. 12 is a schematic diagram explaining the flow of air in the machine room of the chilling unit according to embodiment 1. FIG. 13 is a flowchart showing control when a refrigerant leaks from the chilling unit according to embodiment 1. FIG. 14 is a flowchart showing control of the DCL cooling fan of the chilling unit according to embodiment 1.

[0010] Below, chilling units and air conditioning apparatuses according to embodiments will be described with reference to the drawings. In the following drawings, components with the same reference numerals are the same or equivalent, and will be common throughout the embodiments described below. Furthermore, the size relationships between components in the drawings may differ from those in reality. Furthermore, the configurations of components shown throughout the specification are merely examples and are not limited to the configurations described in the specification. Furthermore, when multiple similar devices are distinguished by subscripts, the subscripts may be omitted if there is no need to distinguish or identify them.

[0011] In the following description, terms indicating directions (such as "up," "down," "right," "left," "front," and "rear") are used as appropriate to facilitate understanding, but these terms are for the purpose of explanation and do not limit the present disclosure. In the embodiment described below, terms such as "up," "down," "right," "left," "front," and "rear" are used when viewing the chilling unit from the front.

[0012] Embodiment 1. Fig. 1 is a perspective view showing the exterior of a chilling unit 100 according to Embodiment 1. The chilling unit 100 in Fig. 1 is shown with the front panel 6 of the housing 1 removed. The chilling unit 100, which is a heat source unit that supplies heat to an indoor unit 200, which serves as a load-side device and will be described later, will now be described. In Embodiment 1, the heat medium that transports heat supplied from the chilling unit 100 and supplies it to the indoor unit 200 is assumed to be water. However, this is not a limitation, and the heat medium may be a fluid containing brine or the like.

[0013] 1, chilling unit 100 has a housing 1, an air heat exchanger 2, and an outdoor fan 3. Housing 1 is located at the bottom of chilling unit 100 and serves as a base that supports chilling unit 100, and has a rectangular box shape in a plan view. Housing 1 also has a machine chamber 9 formed therein, which houses devices that make up the refrigerant circuit.

[0014] The air heat exchanger 2 is one of the components constituting the refrigerant circuit and is a fin-and-tube heat exchanger that exchanges heat between the refrigerant and outdoor air. As described below, the chilling unit 100 according to the first embodiment has multiple refrigerant circuits, and in this example, it has four refrigerant circuits. Therefore, in the chilling unit 100 according to the first embodiment, four air heat exchangers 2A to 2D are installed in the upper part of the housing 1. The air heat exchanger 2A and the air heat exchanger 2B are paired, and the air heat exchanger 2C and the air heat exchanger 2D are paired. When viewed from the short side of the housing 1 indicated by arrow A, the pair of air heat exchangers 2 are arranged opposite each other with a wide gap between them at the top, forming a V-shape. Furthermore, in the chilling unit 100 according to the first embodiment, two pairs of air heat exchangers 2 are arranged in the upper part of the housing 1, aligned along the longitudinal direction of the housing 1. Between the pair of air heat exchangers 2, a blower chamber 22 is formed which communicates with an exhaust port 31, which will be described later.

[0015] The outdoor fan 3 is a propeller fan that passes outdoor air through the air heat exchanger 2. The outdoor fan 3 has its outer periphery covered by a cylindrical fan cover 32. The outdoor fan 3 is positioned above the pair of air heat exchangers 2, between the V-shaped air heat exchangers 2. The chilling unit 100 according to the first embodiment has four outdoor fans 3A to 3D. When the outdoor fans 3 are driven, air surrounding the chilling unit 100 passes through the air heat exchanger 2 and is drawn into the blower chamber 22. The air drawn into the blower chamber 22 is drawn toward an exhaust port 31 formed inside the fan cover 32 and discharged from the exhaust port 31 above the chilling unit 100, i.e., toward the outside. In the following description, the outdoor fan 3 will also be referred to as a fan.

[0016] FIG. 2 is a diagram showing the configuration of an air conditioning system centered around a chilling unit 100 according to Embodiment 1. As shown in FIG. 2, the air conditioning system according to Embodiment 1 has one chilling unit 100 and two indoor units 200. The chilling unit 100 has four refrigerant circuits. Two refrigerant circuits are grouped together and share one water heat exchanger 60. The chilling unit 100 has two groups of two refrigerant circuits. In the heat medium circulation circuit, two water heat exchangers 60 are piped in series, and water, which serves as a heat medium, is cooled or heated in two stages.

[0017] As shown in Figure 2, the refrigerant circuit of each system of the chilling unit 100 according to the first embodiment comprises a compressor 30, a four-way valve 50, an air heat exchanger 2, an expansion valve 70, a water heat exchanger 60, and an accumulator 40, all of which are connected by piping. The refrigerant may be, for example, a single refrigerant such as R-22 or R-134a, a pseudo-azeotropic refrigerant mixture such as R-410A or R-404A, or a non-azeotropic refrigerant mixture such as R-407C. Also, CF4, which contains a double bond in its chemical formula, may be used. ３ CF=CH ２ Refrigerants with relatively low global warming potential, such as CO ２ Natural refrigerants such as propane can be used.

[0018] The compressors 30 (compressors 30A to 30D) compress and discharge the drawn refrigerant. The compressors 30 are driven via a compressor inverter drive device (not shown) or the like. The compressors 30 can change the capacity of the compressors 30, which is the amount of refrigerant delivered per unit time, by arbitrarily changing the drive frequency based on instructions from the control device 300 (control device 300A and control device 300B). Here, the inverter drive device and the control device 300 are control system devices housed in a refrigerant circuit side control box 10 (see FIG. 4), which will be described later.

[0019] Furthermore, the four-way valve 50 (four-way valves 50A to 50D) serving as a flow path switching device switches the flow of refrigerant depending on the operation being performed, based on instructions from the control device 300. For example, during cooling operation, the four-way valve 50 causes the high-temperature, high-pressure refrigerant discharged from the compressor 30 to flow into the air heat exchanger 2. During heating operation, the four-way valve 50 causes the high-temperature, high-pressure refrigerant discharged from the compressor 30 to flow into the water heat exchanger 60.

[0020] As described above, the air heat exchanger 2 (air heat exchanger 2A to air heat exchanger 2D) exchanges heat between the refrigerant and the outside air. In heating operation to heat water, the air heat exchanger 2 functions as an evaporator, exchanging heat between the low-pressure refrigerant flowing in from the expansion valve 70 side and the air, evaporating the refrigerant. In cooling operation to cool water, the air heat exchanger 2 functions as a condenser, exchanging heat between the low-pressure refrigerant flowing in from the compressor 30 side and the air, condensing the refrigerant to a liquid. As described above, the outdoor fan 3 (outdoor fan 3A to outdoor fan 3D) sends air into the air heat exchanger 2 to promote heat exchange between the refrigerant and the air. The outdoor fan 3 is driven via a fan inverter drive device (not shown) or the like. The outdoor fan 3 can change its airflow by arbitrarily changing its drive frequency based on instructions from the control device 300. In FIG. 2, the air heat exchangers 2 and the outdoor fans 3 are in one-to-one correspondence, but this is not particularly limited.

[0021] The water heat exchangers 60 (water heat exchanger 60A and water heat exchanger 60B) function as heat medium heat exchangers, exchanging heat between the refrigerant and water, which serves as a heat medium. The water heat exchanger 60 serves as a flow path for two refrigerant circuits and a flow path for the heat medium circulation circuit. Therefore, the water heat exchanger 60 serves as a component of the refrigerant circuit and a component of the heat medium circulation circuit. For example, during heating operation, the water heat exchanger 60 functions as a condenser, exchanging heat between the refrigerant flowing in from the compressor 30 side and water, condensing the refrigerant to liquefy or convert it into a gas-liquid two-phase mixture, and heating the water. Meanwhile, during cooling operation, the water heat exchanger 60 functions as an evaporator, exchanging heat between the refrigerant flowing in from the expansion valve 70 side and water, evaporating the refrigerant to cool the water.

[0022] The expansion valves 70 (expansion valves 70A to 70D) serving as throttling devices adjust the pressure of the refrigerant passing through the water heat exchanger 60, for example, by changing their opening degrees. The expansion valves 70 according to the first embodiment are configured as electronic expansion valves that change their opening degrees based on instructions from the control device 300 described above. However, the present invention is not limited to this. For example, the expansion valves may be temperature-sensing expansion valves that change their opening degrees based on the temperature of the refrigerant.

[0023] The accumulators 40 (accumulators 40A to 40D) are each provided on the suction side of the compressor 30, and store surplus refrigerant in the refrigerant circuit.

[0024] The pump 80 is one of the devices constituting the heat medium circulation circuit. In the heat medium circulation circuit, the pump 80 sucks water, applies pressure, and sends it out to circulate. A pump inverter drive device (not shown) can change the capacity of the pump 80 by arbitrarily changing the drive frequency based on instructions from a pump-side control device (not shown). The pump inverter drive device and the pump-side control device are control system devices housed in a pump control box 90 (see FIG. 6 ), which will be described later.

[0025] The indoor units 200 are units that send conditioned air to the indoor space that is the target of air conditioning. The indoor units 200 (indoor unit 200A and indoor unit 200B) have indoor heat exchangers 201 (indoor heat exchanger 201A and indoor heat exchanger 201B), indoor flow control devices 202 (indoor flow control devices 202A to 202B), and indoor fans 203 (indoor fans 203A to 203B). The indoor heat exchanger 201 and the indoor flow control devices 202 are devices that make up a heat medium circulation circuit. Note that while FIG. 2 shows an air conditioner having two indoor units 200, the number of indoor units 200 is not particularly limited.

[0026] The indoor flow control device 202 is configured, for example, as a two-way valve capable of controlling the valve opening (opening area). By adjusting its opening, the indoor flow control device 202 controls the flow rate of water flowing into and out of the indoor heat exchanger 201. The indoor flow control device 202 adjusts the amount of water passing through the indoor heat exchanger 201 based on the temperatures of the water flowing into and out of the indoor unit 200, enabling the indoor heat exchanger 201 to exchange heat at a rate appropriate to the indoor heat load. When the indoor heat exchanger 201 does not need to exchange heat with the heat load, such as when the indoor unit is stopped or the thermostat is turned off, the indoor flow control device 202 can fully close the valve to stop the supply of water to and from the indoor heat exchanger 201. In FIG. 2 , the indoor flow control device 202 is installed on the piping on the water outlet side of the indoor heat exchanger 201, but this is not a limitation. For example, the indoor flow control device 202 may be installed on the water inlet side of the indoor heat exchanger 201.

[0027] The indoor heat exchanger 201 exchanges heat between the indoor air in the indoor space supplied from the indoor fan 203 and water. When water cooler than the air passes through the heat transfer tube, the air is cooled and the indoor space is cooled. The indoor fan 203 passes the air in the indoor space through the indoor heat exchanger 201 and generates a flow of air that returns the air to the indoor space.

[0028] FIG. 3 is a perspective view showing the housing 1 of the chilling unit 100 according to the first embodiment. FIG. 4 is a partially enlarged view of the housing 1 shown in FIG. 3. FIG. 5 is a view showing a portion of the internal configuration of the housing 1 shown in FIG. 3. FIG. 6 is a schematic diagram illustrating the arrangement of devices in the machine room 9 of the chilling unit 100 according to the first embodiment. FIG. 7 is a perspective view of the refrigerant circuit control box 10 of the chilling unit 100 according to the first embodiment, seen from the rear side. FIG. 8 is a perspective view of the DCL box 110 of the chilling unit 100 according to the first embodiment. FIG. 9 is a schematic diagram illustrating the flow of air in the machine room 9 of the chilling unit 100 according to the first embodiment. Note that FIG. 4 shows the housing 1 with the front panel 6 removed. FIG. 5 is a view of a portion of the machine room 9 of the housing 1, seen from above. Arrows in FIG. 9 indicate the flow of air.

[0029] As described above, the machine room 9 of the chilling unit 100 according to the first embodiment includes the components constituting the refrigerant circuit, the components constituting the heat medium circuit, and the control system components that control these components. FIG. 6 shows four compressors 30 (compressors 30A to 30D), four accumulators 40 (accumulators 40A to 40D), and four four-way valves 50 (four-way valves 50A to 50D). Two water heat exchangers 60 (water heat exchanger 60A and water heat exchanger 60B) are also shown. Although not shown in FIG. 6, the machine room 9 also includes four expansion valves 70 (expansion valves 70A to 70D). The machine room 9 also includes a pump 80 that constitutes the heat medium circuit through which water, the heat medium, circulates.

[0030] Furthermore, the machine room 9 has two refrigerant circuit side control boxes 10 (refrigerant circuit side control box 10A and refrigerant circuit side control box 10B) that house control system devices, etc., a pump control box 90, a power supply terminal box 20, and a DCL box 110. Note that, hereinafter, the refrigerant circuit side control box 10 will also be referred to as the control box.

[0031] In the machine room 9, the power supply terminal box 20 is arranged closest to the side indicated by arrow A in Figures 5 and 6. Next, the DCL box 110 is arranged close to one of the longitudinally extending side surfaces. Next, a plurality of refrigerant circuit side control boxes 10 are arranged side by side in the longitudinal direction of the machine room 9, close to one of the longitudinally extending side surfaces. Furthermore, devices that make up the refrigerant circuit are arranged on the other longitudinal side surface opposite the side on which the plurality of refrigerant circuit side control boxes 10 are arranged.

[0032] In the machine room 9, the compressors 30, accumulators 40, four-way valves 50, and expansion valves 70 are grouped by system and arranged side by side in the longitudinal direction. Because the compressors 30 and accumulators 40 have large volumes, they are arranged side by side along the other longitudinal side. Therefore, the compressors 30 and accumulators 40, the refrigerant circuit control boxes 10, and the DCL boxes 110 are arranged in parallel in the lateral direction of the machine room 9. Furthermore, next to the refrigerant circuit control boxes 10, the compressors 30, and the accumulators 40, are the equipment constituting the refrigerant circuit and the equipment constituting the heat medium circuit. The pump 80 and pump control box 90 constituting the heat medium circuit are arranged farthest from the arrow A side. Therefore, the equipment in the refrigerant circuit system and the equipment in the heat medium circuit system are arranged separated by the water heat exchanger 60.

[0033] The power terminal box 20 is a box that houses power terminals (not shown). Electrical equipment within the refrigerant circuit control box 10 and the pump control box 90, such as inverters with power modules that drive the equipment and control boards with control devices 300, receives power via power terminals connected to external wiring. For example, when multiple chilling units 100 are installed, the longitudinal sides of the machine chambers 9 of the chilling units 100 are placed facing each other. Therefore, providing power terminals on the longitudinal sides of the chilling units 100 makes wiring connections difficult. Therefore, the power terminal box 20 is housed at one end of the machine chamber 9 closest to the arrow A, so that the power terminals are visible from the shorter side of the machine chamber 9 and can be easily connected to external wiring.

[0034] Meanwhile, a pump 80, one of the components of the heat medium circuit, is housed at the other end of the machine room 9, farthest from the arrow A, opposite the end where the power supply terminal box 20 is housed. Next to the pump 80 are multiple water heat exchangers 60, which are components of the refrigerant circuit and heat medium circuit. For example, the pump 80 and multiple water heat exchangers 60 housed in the machine room 9 of the chilling unit 100 need to be connected to other devices that have components of the heat medium circuit. For this reason, the pump 80 is housed at the other end of the machine room 9, farthest from the arrow A, so that the heat medium piping connected to the pump 80 and multiple water heat exchangers 60 is visible from the short side and for easy piping connection. The pump control box 90 is located adjacent to the pump 80, on the same side of the long side of the machine room 9 as the multiple refrigerant circuit control boxes 10. Therefore, workers do not need to move to perform maintenance on the electrical equipment inside the pump control box 90.

[0035] As shown in FIGS. 3 and 4 , the housing 1 includes a drain plate 5 on the top surface, a front panel 6 on the front surface, a bottom plate 7 on the bottom surface, and a refrigerant leak detection unit 8 located near the bottom plate 7. The drain plate 5 receives condensation water generated in the air heat exchanger 2. The drain plate 5 has multiple openings 5a. These multiple openings 5a communicate with the blower chamber 22 and allow air in the machinery chamber 9 to pass to the upper blower chamber 22. One of the multiple openings 5a is located above the DCL box 110. The front panel 6 is detachably attached to the front of the housing 1 and can be attached or detached during maintenance. The bottom plate 7 is used to place the equipment in the machinery chamber 9. The bottom plate 7 also receives condensation water generated in the air heat exchanger 2, catching any condensation water not received by the drain plate 5. The refrigerant leakage detector 8 is provided on the bottom plate 7 near a refrigerant circuit side control box 10 that may be an ignition source in the machine room 9, and detects refrigerant leakage.

[0036] 7, each refrigerant circuit side control box 10 has a compression board heat sink 11, a fan board heat sink 12, and a heat sink cooling fan 13. The compression board heat sink 11, the fan board heat sink 12, and the heat sink cooling fan 13 are each installed outside the box of each refrigerant circuit side control box 10.

[0037] The compression board heat sink 11 comes into contact with electronic components of a compressor inverter drive device housed in the refrigerant circuit-side control box 10 that drives the compressor 30, and dissipates heat generated by the operation of the electronic components. The fan board heat sink 12 comes into contact with electronic components of a fan inverter drive device housed in the refrigerant circuit-side control box 10 that drives the outdoor fan 3, and dissipates heat generated by the operation of the electronic components. The heat sink cooling fan 13 sends air from below the compression board heat sink 11 and the fan board heat sink 12 to promote heat dissipation in the compression board heat sink 11 and the fan board heat sink 12. By creating an air flow from the bottom to the top of the compression board heat sink 11 and the fan board heat sink 12, heat can be dissipated efficiently.

[0038] As shown in FIG. 8 , the DCL box 110 has a plurality of (four in the first embodiment) DC reactors 111, a temperature detection unit 112 provided in one of the plurality of DC reactors 111, and a DCL cooling fan 113 provided on the top of the DCL box 110.

[0039] The DC reactor 111 is a type of electronic component. The temperature detector 112 is, for example, a thermistor and detects the temperature of the DC reactor 111. The DCL cooling fan 113 generates an airflow in the vertical direction, drawing air from below the DC reactors 111 and sending it to the reactors, thereby promoting heat dissipation in the reactors 111. By operating the DCL cooling fan 113, an airflow is formed from below the DC reactors 111 to above them, as shown in FIG. 9 . In this way, by forming an airflow from below the DC reactors 111 to above them by the DCL cooling fan 113, heat can be efficiently dissipated from the reactors. Furthermore, an opening 5 a provided in the drain plate 5 is located above the DCL cooling fan 113. In other words, the DCL cooling fan 113 is located below the opening 5 a. Therefore, the air formed by the DCL cooling fan 113 and flowing from below the plurality of DC reactors 111 to above is easily drawn into the fan chamber 22 through the opening 5a located above the DCL cooling fan 113. As a result, the air drawn into the fan chamber 22 can be easily discharged to the outside through the exhaust port 31.

[0040] As shown in Figures 5 and 6, the DCL box 110 is independently provided outside the refrigerant circuit control box 10 and to the side of the refrigerant circuit control box 10 (in the longitudinal direction of the housing 1). Also, as shown in Figure 8, the DCL cooling fan 113 is provided on top of the DCL box 110. Therefore, as shown in Figure 9, when the DCL cooling fan 113 is operated, the airflow generated by the DCL cooling fan 113 does not pass through the refrigerant circuit control box 10. As a result, in the event of a refrigerant leak, the refrigerant accumulated in the area surrounded by the dashed line in Figure 9 is prevented from flowing toward an ignition source within the refrigerant circuit control box 10, and the refrigerant is directed above the DCL cooling fan 113, away from the ignition source. Also, as shown in Figure 9, the refrigerant leak detection unit 8 is provided on the bottom plate 7 near the refrigerant circuit control box 10, which could be an ignition source within the machine room 9. Here, if refrigerant leaks from the refrigerant circuit, the refrigerant will accumulate in the lower part of the machine room 9, so by providing the refrigerant leakage detection unit 8 on the bottom plate 7, it is possible to quickly detect the refrigerant leakage. In addition, by providing the refrigerant leakage detection unit 8 near the refrigerant circuit side control box 10, which is a potential ignition source, it is possible to quickly detect that refrigerant has accumulated near the ignition source.

[0041] 10 is a flowchart showing control when a refrigerant leaks from the chilling unit 100 according to embodiment 1. The control when a refrigerant leaks from the chilling unit 100 according to embodiment 1 will be described below with reference to FIG.

[0042] (Step S101) The control device 300 determines whether a refrigerant leak has been detected by the refrigerant leak detection unit 8. If the control device 300 determines that a refrigerant leak has been detected (YES), the process proceeds to step S102. On the other hand, if the control device 300 determines that a refrigerant leak has not been detected (NO), the process repeats step S101.

[0043] (Step S102) The control device 300 operates the DCL cooling fan 113 at the maximum rotation speed (maximum airflow). If the DCL cooling fan 113 is stopped, it is started and operated at the maximum rotation speed. If the DCL cooling fan 113 is operating at a speed other than the maximum rotation speed, the rotation speed is changed to the maximum rotation speed. If the DCL cooling fan 113 is operating at the maximum rotation speed, it continues to operate as is.

[0044] In this way, by operating the DCL cooling fan 113 at the maximum rotation speed (maximum airflow) when a refrigerant leak is detected, the refrigerant can be quickly moved away from sources of ignition in the event of a refrigerant leak.

[0045] 11 is a flowchart showing the control of the DCL cooling fan 113 of the chilling unit 100 according to embodiment 1. The control of the DCL cooling fan 113 of the chilling unit 100 according to embodiment 1 will be described below with reference to FIG.

[0046] (Step S201) The control device 300 detects the temperature T of the DC reactor 111 detected by the temperature detection unit 112. ＤＣＬ is the first threshold TH １ The control device 300 determines whether the temperature of the DC reactor 111 is equal to or lower than the first threshold value TH １ Below (T ＤＣＬ ≦TH １ On the other hand, if the control device 300 determines that the temperature of the DC reactor 111 is equal to or lower than the first threshold value TH １ Greater than (T ＤＣＬ >TH １ If it is determined that the number of the spooled packets is 1 or more (NO), the process proceeds to step S203.

[0047] (Step S202) The control device 300 operates the DCL cooling fan 113 at the minimum rotation speed.

[0048] (Step S203) The control device 300 detects the temperature T of the DC reactor 111 detected by the temperature detection unit 112. ＤＣＬ is the first threshold TH １ is greater than the second threshold TH ２ (>First threshold TH１ The control device 300 determines whether the temperature of the DC reactor 111 is equal to or lower than the first threshold value TH １ is greater than the second threshold TH ２ Below (TH １ <T ＤＣＬ ≦TH ２ On the other hand, if the control device 300 determines that the temperature of the DC reactor 111 is equal to or lower than the second threshold value TH ２ Greater than (T ＤＣＬ >TH ２ If it is determined that the number of the spooled packets is 1 or more (NO), the process proceeds to step S205.

[0049] (Step S204) The control device 300 operates the DCL cooling fan 113 at an intermediate rotation speed.

[0050] (Step S205) The control device 300 operates the DCL cooling fan 113 at the maximum rotation speed.

[0051] In this way, by controlling the rotation speed (air volume) of the DCL cooling fan 113 in accordance with the temperature of the DC reactor 111, it is possible to suppress energy consumption while preventing the temperature of the DC reactor 111 from rising excessively. Note that, although the rotation speed of the DCL cooling fan 113 is controlled in three stages in the above, it is not limited thereto, and may be controlled in two stages or in four or more stages.

[0052] As described above, the chilling unit 100 according to the first embodiment comprises a housing 1 having a machine chamber 9 formed therein, an air heat exchanger 2 provided on top of the housing 1 and forming a blower chamber 22, and a fan provided on top of the air heat exchanger 2 for discharging air from the blower chamber 22 to the outside. The machine chamber 9 comprises a DCL box 110 having a DC reactor 111 and a DCL cooling fan 113 for cooling the DC reactor 111, and a control box having a control device 300 for controlling the DCL cooling fan 113. The DCL cooling fan 113 is provided so that when the DCL cooling fan 113 is operating, the air flow generated by the DCL cooling fan 113 does not pass through the control box.

[0053] According to the chilling unit 100 of the first embodiment, the DCL box 110 includes a DC reactor 111 and a DCL cooling fan 113 that cools the DC reactor 111. Therefore, the DCL cooling fan 113 can cool the DC reactor 111, preventing the DC reactor 111 from overheating. The DCL cooling fan 113 is also provided to prevent the airflow generated by the DCL cooling fan 113 from passing through the control box when the DCL cooling fan 113 is operating. Therefore, the airflow generated by the DCL cooling fan 113 can move the refrigerant away from the control box, where an ignition source may exist, in the event of a refrigerant leak. As described above, the chilling unit 100 of the first embodiment can move the refrigerant away from the control box, where an ignition source may exist, in the event of a refrigerant leak, while preventing the DC reactor 111 from overheating.

[0054] In addition, in the chilling unit 100 according to embodiment 1, the housing 1 is provided with a drain plate 5 on the top surface, which has an opening 5a that connects the blower chamber 22 and the machine chamber 9, and the DCL cooling fan 113 is provided below the opening 5a.

[0055] According to the chilling unit 100 of the first embodiment, air flowing from below the DC reactor 111 to above the DC reactor 111 is easily drawn into the fan chamber 22 through the opening 5a located above the DCL cooling fan 113. As a result, the air drawn into the fan chamber 22 can be easily discharged to the outside.

[0056] Furthermore, in the chilling unit 100 according to the first embodiment, the DCL box 110 is provided with a temperature detection unit 112 that detects the temperature of the DC reactor 111, and the control device 300 controls the rotation speed of the DCL cooling fan 113 based on the temperature detected by the temperature detection unit 112.

[0057] According to the chilling unit 100 of embodiment 1, by controlling the rotation speed (air volume) of the DCL cooling fan 113 in accordance with the temperature of the DC reactor 111, it is possible to suppress the temperature of the DC reactor 111 from rising too much and to suppress energy consumption.

[0058] Furthermore, in the chilling unit 100 according to the first embodiment, the machine room 9 is provided with a refrigerant leak detection unit 8 on the bottom surface thereof for detecting refrigerant leaks, and the control device 300 maximizes the rotation speed of the DCL cooling fan 113 when the refrigerant leak detection unit 8 detects a refrigerant leak.

[0059] According to the chilling unit 100 of the first embodiment, when a refrigerant leak is detected, the DCL cooling fan 113 is operated at the maximum rotation speed (maximum airflow), thereby enabling the refrigerant to be quickly moved away from sources of ignition in the event of a refrigerant leak.

[0060] 1 Housing, 2 Air heat exchanger, 2A Air heat exchanger, 2B Air heat exchanger, 2C Air heat exchanger, 2D Air heat exchanger, 3 Outdoor fan, 3A Outdoor fan, 3B Outdoor fan, 3C Outdoor fan, 3D Outdoor fan, 5 Drain plate, 5a Opening, 6 Front panel, 7 Bottom plate, 8 Refrigerant leak detection unit, 9 Machine room, 10 Refrigerant circuit side control box, 10A Refrigerant circuit side control box, 10B Refrigerant circuit side control box, 11 Compression board heat sink, 12 Fan board heat sink, 13 Heat sink cooling fan, 20 Power supply terminal box, 22 Blower room, 30 Compressor, 30A Compressor, 30B Compressor, 30C Compressor, 30D Compressor, 31 Exhaust port, 32 Fan cover, 40 Accumulator, 40A Accumulator, 40B Accumulator, 40C Accumulator, 40D Accumulator, 50 Four-way valve, 50A Four-way valve, 50B Four-way valve, 50C Four-way valve, 50D Four-way valve, 60 Water heat exchanger, 60A Water heat exchanger, 60B Water heat exchanger, 70 Expansion valve, 70A Expansion valve, 70B Expansion valve, 70C Expansion valve, 70D Expansion valve, 80 Pump, 90 Pump control box, 100 Chilling unit, 110 DCL box, 111 DC reactor, 112 Temperature detection unit, 113 DCL cooling fan, 200 Indoor unit, 200A Indoor unit, 200B Indoor unit, 201 Indoor heat exchanger, 201A Indoor heat exchanger, 201B Indoor heat exchanger, 202 Indoor flow rate adjustment device, 202A Indoor flow rate regulator, 202B indoor flow rate regulator, 203 indoor fan, 203A indoor fan, 203B indoor fan, 300 control device, 300A control device, 300B control device.

Claims

1. A chilling unit comprising: a housing with a machine chamber formed therein; an air heat exchanger provided on top of said housing and forming a blower chamber; and a fan provided on top of said air heat exchanger and discharging air from said blower chamber to the outside, wherein said machine chamber comprises: a DCL box having a DC reactor and a DCL cooling fan for cooling said DC reactor; and a control box having a control device for controlling said DCL cooling fan, wherein said DCL cooling fan is provided so that when said DCL cooling fan is operating, the air flow generated by said DCL cooling fan does not pass through the control box.

2. The chilling unit according to claim 1, wherein the DCL box is provided independently to the side of the control box, and the DCL cooling fan is provided above the DCL box.

3. The chilling unit according to claim 1 or 2, wherein the housing is provided with a drain plate on the top surface, with an opening formed therein that connects the blower chamber and the machine chamber, and the DCL cooling fan is provided below the opening.

4. A chilling unit as claimed in any one of claims 1 to 3, wherein the DCL box is provided with a temperature detection unit that detects the temperature of the DC reactor, and the control device controls the rotation speed of the DCL cooling fan based on the temperature detected by the temperature detection unit.

5. A chilling unit as claimed in any one of claims 1 to 4, wherein the machine room is provided with a refrigerant leak detection unit provided on the bottom surface for detecting refrigerant leaks, and the control device maximizes the rotation speed of the DCL cooling fan when the refrigerant leak detection unit detects a refrigerant leak.

6. An air conditioning device equipped with a chilling unit according to any one of claims 1 to 5.

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