Air-conditioning system for communication instruments, etc

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to an air conditioning system for a room having a high heat generation density, such as a communication equipment room.

【0002】

[Conventional technology]

In the computer room and OA room, most of the air conditioning heat load is sensible heat load, and the average heat generation density per floor area is 500 W / m.²Degree. In such facilities, full-scale heat treatment type packaged air conditioners are often used because of their ease of construction and maintenance and the ability to disperse heat sources.

【0003】

In addition, the room structure of these facilities has a double-floor structure because it is necessary to wire a large number of power cables and signal cables, and the underfloor chamber is used as a wiring space. In order to use the underfloor chamber as an air passage even in air conditioning with a package air conditioner, the upper suction / lower blowout method is used, and the low-temperature air processed by the package air conditioner is transported to the installation location of a computer, etc. through the underfloor chamber, and the lower part of the equipment. The low-temperature air is supplied to the inside of the equipment housing through the opening of the device to treat the exhaust heat from the equipment.

【0004】

FIG. 11 shows a method of configuring such a conventional air conditioning system. The fully exposed heat treatment type package air conditioner 101 used has a direct expansion coil 101a and a blower 101b, and the direct expansion coil 101a is an outdoor unit 101c and a refrigerant pipe 101d installed outside the communication device room R. It is tied. The temperature of the air blown from this full-scale heat treatment type package air conditioner 101 is usually 15 to 20 ° C, and the exhaust from the equipment housing 102 and the outlet 103a of the floor surface 103 in the room R into the room, the equipment. The temperature of the air mixed with the air blown out from the outlet 103b corresponding to the above, that is, the return air temperature to the package air conditioner 101 is about 25 ° C. Therefore, the processing temperature difference in the full-scale heat treatment type packaged air conditioner 101 is about 5 to 10 ° C. The cooling capacity of each fully-exposed heat-treated packaged air conditioner currently on the market is about 10 to 40 kW, and the number of packaged air conditioners installed along the outer wall surface of the facility according to the air conditioning heat load is installed indoors. Air conditioning is performed.

【0005】

In addition to the above-mentioned package air conditioner method, there is a method of using an air conditioner with a built-in chilled water coil as a cooling device. In this case, a refrigerator and a cooling tower are used as the heat source device. For example, in the one disclosed in Japanese Patent No. 2979061, two cooling coils are arranged in series with respect to the flow of processed air in an air conditioner to perform primary cooling + secondary cooling. In this open technology, the cold water supply to the primary cooling coil can be switched between the cold water system made by the refrigerator and the cold water system made by the free cooling of the cooling tower. In winter and in the middle of the period when the outside air wet-bulb temperature is low, cold water is supplied by free cooling of the cooling tower to reduce the operating time of the refrigerator and save energy. Furthermore, by using two cooling coils for primary cooling and secondary cooling in series, the change in cooling capacity due to fluctuations in outside air conditions when the free cooling operation of the cooling tower is performed for primary cooling is corrected by secondary cooling. It is something to try.

【0006】

[Problems to be Solved by the Invention]

By the way, with the development of communication technology such as the Internet, many communication bases have been constructed. In the communication equipment room in these facilities, as shown in FIG. 12, a large number of racks 111 containing a plurality of communication equipment such as servers and routers are arranged in the communication equipment room. Most of the heat load of air conditioning in these facilities is also sensible heat load, and the heat generation density is considerably larger than that of a general computer room. This trend is expected to continue for the foreseeable future, with an average heat generation density of 1000 W / m per floor area.²Is expected to exceed.

【0007】

When air-conditioning a communication equipment room with such a high heat generation density, the method of increasing the number of conventional full-scale heat treatment type package air conditioners used in the above-mentioned computer room or the like according to the heat load is used. , The number of packaged air conditioners installed will increase significantly, and there is a risk that indoor units cannot be installed only on the indoor walls of the facility. In addition, as the number of packaged air conditioners installed increases, the amount of air blown air increases significantly, and the air blown resistance in the space below the double floor also increases. Therefore, in the conventional method of adding a packaged air conditioner, it is not only difficult to secure the installation space for the indoor unit, but also the blowing energy is increased. Furthermore, if the area of the communication equipment room becomes large or the amount of communication cables in the underfloor chamber increases, it becomes impossible to blow air uniformly into the underfloor chamber, and the cooling capacity of the equipment varies.

【0008】

Furthermore, according to the latter open technology, the cold heat source is a centralized heat source of the same system, and if a failure or accident occurs around the refrigerator in the operation mode using only the refrigerator in summer, the air conditioning heat source will completely stop. There is a danger that it will end up. In addition, in the case of repair or maintenance of an air conditioner, one air conditioner will be completely stopped, and the room temperature in the area covered by the air conditioner will rise. In addition, in facilities where the heat load of air conditioning is extremely large, the installed capacity also increases, so the space for installing heat source equipment (refrigerator / cooling tower) and the amount of piping become enormous, and a large machine room and pipe shaft space are required. There is also a problem that the ability is reduced.

【0009】

The common problems in each of the above-mentioned prior arts are that as the air-conditioning heat load increases, the installation area of the air-conditioning equipment that air-conditions the room to be cooled increases, the rentability decreases, and through the underfloor chamber. This is an increase in blast energy by circulating conditioned air throughout the room.

【0010】

The present invention has been made in view of this point, and effectively treats the exhaust heat of the equipment in the rack on which the communication equipment or the like is mounted to reduce the heat load on the air conditioning and to reduce the installation space of the air conditioning equipment. The purpose is to solve the above problems by devising.

【0011】

[Means for solving problems]

In order to achieve the above object, according to claim 1, a system in which racks on which communication devices are mounted in the vertical direction are arranged to form a rack row, and an air conditioner is provided in a communication equipment room in which a plurality of the rack rows are installed. Further, an air conditioning system such as a communication equipment room is provided, which comprises a local cooling device for cooling the space above the space formed between the rack rows.

【0012】

By having a local cooling device for cooling the space above the space formed between the rack rows in this way, it is possible to reduce the heat load of the rack through the space. In addition, since the local cooling device is installed above the space formed between the rack rows, the floor occupancy area does not increase. The term "communication equipment room, etc." as used herein refers not only to a room in which the above-mentioned communication equipment is installed, but also to a room in which a high-density heat-generating device is installed, which has a high calorific value. There is. Therefore, it may be a computer room.

【0013】

A local cooling device that cools the aisle space only above the aisle space, with the space formed for each of the two rack rows as the aisle space among the spaces formed between the rack rows. The heat load on the rack can be reduced more efficiently by installing. In other words, when there are multiple rack rows, the local cooling device is installed in every other space, that is, in the aisle space, instead of installing the local cooling device in all the spaces formed between the rack rows. This makes it possible to reduce the heat load on the racks in all rack rows.

【0014】

If the local cooling device has a top plate arranged above the passage space portion and is arranged so as to cover the upper part of the passage space portion together with the top plate, the upper part of the passage space portion is cooled. Since it can be closed except for the space, it is possible to efficiently perform exhaust heat treatment of the communication equipment mounted on the rack by cooling the passage space. In addition, the exhaust gas can be concentrated in the local cooling device.

【0015】

Further, if a hanging plate hanging from the top plate is provided on the longitudinal end surface of the rack row in the aisle space, or a door body capable of closing the aisle space is further added, the aisle space is further closed. Since it can be brought closer to the above, it is possible to carry out exhaust heat treatment of the communication equipment mounted on the rack more efficiently by cooling the aisle space. Moreover, there is no hindrance to the entry of workers into the aisle space.

【0016】

It is preferable that the rack has an opening in a portion facing the aisle space, and a blower for exhausting the atmosphere inside the rack to the outside of the rack is provided in the upper part of the rack. By operating the blower, the conditioned air of the local cooling device supplied to the aisle space can be positively taken into the rack through the opening, and the exhaust heat treatment of the communication equipment mounted on the rack is further effective. Can be implemented as a target. It is more effective when the rack itself has a closed casing. Further, when applied to such a closed casing, there is an advantage that hot heat is not released to the surroundings.

【0017】

When the rack is installed on a double floor constituting the underfloor chamber, an opening leading to the underfloor chamber is formed on the lower surface of the rack, and the underfloor chamber is formed on the lower surface of the passage space, that is, the floor surface. It is preferable that an introduction port leading to the above is formed, and a blower for exhausting the atmosphere inside the rack to the outside of the rack is provided at the upper part of the rack. By operating the blower, the conditioned air of the local cooling device can be positively taken into the rack from the lower surface of the rack through the opening located on the lower surface of the rack through the underfloor chamber, and the communication equipment and the like mounted on the rack are discharged. The heat treatment can be carried out more effectively. This is especially useful if the rack itself has a closed casing.

【0018】

By arranging a diffusion control plate that suppresses the diffusion of the atmosphere in the space above the space formed between the rack rows other than the aisle space, the high temperature air discharged from the rack is discharged from the space. It is possible to prevent the invasion of the space and improve the temperature environment of the open space.

【0019】

A plurality of local cooling devices are installed in the passage space, and a temperature sensor for measuring the temperature of the passage space, for example, a representative temperature of one or a plurality of places in the passage space, and each temperature sensor for each local cooling device. If a control device for controlling the cooling temperature by each local cooling device is provided based on the measurement result of the above, it is possible to carry out efficient and appropriate air conditioning of the passage space and perform exhaust heat treatment of the rack. In this case, it is not necessary for all the local cooling devices to have a temperature sensor. For example, a temperature sensor may be installed in each passage space and the temperature sensor may be used for measurement.

【0020】

The local cooling device has a direct expansion coil as a cooling means, and if it is provided with a control device for controlling the refrigerant evaporation temperature of the direct expansion coil higher than the dew point temperature of the processing air, a rack or the like can be provided. It is possible to prevent an unexpected situation from being given to the communication device or the like mounted on the vehicle due to water leakage or the like. In this case, if necessary, the outside air is separately set in the communication equipment room. The outside air conditioner that is dehumidified or humidified so as to match the dew point temperature and supplied to the room, or the dew point temperature of the indoor atmosphere is the failure of the outside air conditioner. By providing a dehumidifying device for dehumidifying to the set value when the set value is exceeded due to the above, such so-called dry coil operation can be easily controlled.

【0021】

Regarding the air conditioning in the communication equipment room, in the structure in which the passage space is a closed space as shown in claim 5, the air processed by the local cooling device is allowed to flow into the underfloor chamber to reach the floor surface of the open space. It can be blown out from the provided opening. Alternatively, as in the conventional case, for example, a full-scale heat treatment type package air conditioner may be installed to blow out conditioned air from the floor surface through the underfloor chamber.

【0022】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the present invention will be described. FIG. 1 shows an outline of the inside of a communication equipment room having an air conditioning system according to the first embodiment. In this illustrated example, a row of racks L in which communication equipment and the like are mounted is a rack. There are 4 rows L1 to L4. The space between the rack rows L1 and the rack rows L2 forms the aisle space 1, and the space between the rack rows L3 and the rack rows L4 forms the aisle space 2. The space between the rack rows L2 and the rack rows L3 forms an open space 3.

【0023】

A general rack conventionally used in this type of communication equipment room R has only the bottom and top open, and a door that can be opened and closed for maintenance and inspection is provided on the front side. Has basically the same structure, and a door (not shown) that can be opened and closed is provided on the front surface (opposing surface), and communication equipment such as a server is provided in the rack L. It is fixed on the rail (not shown) and is stacked in multiple stages.

【0024】

Further, in the present embodiment, the front surfaces of the rack rows L1 and the rack rows L2, and the rack rows L3 and the rack rows L4 face each other, that is, they face each other, with the front surface of each rack L facing upside down for each rack row. However, each rack L in each rack row may be arranged in the same orientation, that is, the front surface of the rack L faces the back surface of the racks in the other rack rows. Even in that case, for convenience, it may be treated as a passage space 2 and an open space 3 every other space. [0025]

As shown in the figure, in a general communication equipment room, racks L for storing or mounting communication equipment are often arranged in a row with a maintenance passage portion separated from each other. The space portion 3 corresponds to such a maintenance passage, and its width is about 800 to 1000 mm.

【0026】

A blower 4 for exhausting the atmosphere inside the rack L to the outside of the rack is installed on the top plate portion of each rack L. As shown in FIG. 2, the rack L itself has a casing 6 for accommodating the communication device 5 inside, and openings 6a are provided on the side surfaces of the casing 6 facing the aisle spaces 1 and 2, respectively. Is formed. The opening may be formed of punching metal. That is, when the rack L has an opening / closing door (not shown) on the front surface (opposing surface), a slit or a ventilation hole is formed in the opening / closing door itself, or the opening / closing door itself is made of punching metal. If there is no such door, a slit may be formed in the panel itself forming the side plate (front plate), a ventilation hole may be formed, or the panel itself may be made of punching metal. The communication equipment room R has a double floor structure, and an underfloor chamber 7 is formed under the floor surface F. The rack L is installed on the floor surface F. Further, on the floor surface F in the passage space portions 1, 2 and the space portion 3, an appropriate opening 8 leading to the underfloor chamber 7 is provided.

【0027】

A plurality of top plates 11 and local cooling devices 12 are installed on the passage space portions 1 and 2, and both cover the upper part of the passage space portions 1 and 2. FIG. 3 shows the structure of the local cooling device 12 installed above the passage space 1. The local cooling device 12 is installed on, for example, the pedestals 13 and 13 provided on the facing surfaces of the rack rows L1 and L2.

【0028】

The local cooling device 12 has at least a cooling coil and a blower. In the present embodiment, the two cooling coils 14, 15 provided so as to be substantially located along the longitudinal direction of the rack rows L1 and L2, that is, substantially on the facing surfaces of the racks L of the rack rows L1 and L2 facing each other. The cross flow fan 16 is located between the cooling coils 14 and 15 and serves as a blower for sucking the atmosphere on the rack L through the cooling coils 14 and 15 and blowing the air into the lower passage space 1. I have. Therefore, the air sucked into the cooling coils 14 and 15 is discharged downward through the discharge chamber 16a of the cross flow fan 16 and the discharge port face 16b having a diffusion action by a diffusion plate or the like.

【0029】

The cooling coils 14 and 15 are direct expansion type cooling coils, and as shown in FIG. 2, a refrigerant pipe 18 is installed between the cooling coils 14 and 15 and the outdoor unit 17 installed outside the communication equipment room R. The refrigerant from the refrigerant pipe 18 is supplied to the cooling coils 14 and 15 via the electronic expansion valve 19. The refrigerant pipe 18 passes through the upper part of the communication equipment room R, for example, and several local cooling devices 12 can be connected to the refrigerant pipe 18. The outdoor unit 17 can be either water-cooled or air-cooled.

【0030】

The local cooling device 12 has a power supply / control box 20 at the upper part, and further has a control device 21 on the outdoor unit 17 side as shown in FIG. The power supply / control box 20 and the control device 21 are configured to control the temperature of the cooling device 12 based on the measurement results of the temperature sensor 22 installed in the passage space 1. The refrigerant evaporation temperature of the cooling coils 14 and 15 is controlled to be higher than the indoor air dew point temperature of the communication equipment room R, and is normally operated as a dry coil.

【0031】

The temperature of the local cooling device 12 is controlled by adjusting the opening degree of the electronic expansion valve 19 and controlling the capacity of the compressor 17a of the outdoor unit 17 by the temperature sensor 22 installed on the outlet side of the local cooling device 12. .. In addition, a plurality of local cooling devices 12 are installed above the aisle space, and this is determined according to the amount of heat generated from the rack L.

【0032】

In the example of FIG. 4, a plurality of local cooling devices 12 are controlled based on the measurement results of the temperature sensors 22 installed at one place in the passage space 1, as shown in FIG. In addition, a dedicated temperature sensor 22 may be installed for each local cooling device 12, and each local cooling device 12 may be individually controlled. In this case, when there is a large difference in the heat generated by the facing rack L in the aisle space 1 for each rack, it is possible to deal with it more appropriately.

【0033】

The bottom plate 23 of the housing of the local cooling device 12 also serves as a waterproof pan, and if dew condensation occurs due to dew condensation, it collects in the bottom plate 23 and does not splash on the communication equipment in the rack L. Is considered. A dew condensation sensor 24 is provided in the bottom plate 23, and when dew condensation water collects in the bottom plate 23, the dew condensation sensor 24 alerts and forcibly operates, for example, stops the compressor 17a of the outdoor unit 17. Program is incorporated in the control device 21.

【0034】

Further, in the present embodiment, the outside air processing unit 31 is installed in the communication equipment room R in order to more reliably operate the dry coil of the local cooling device 12. The outside air processing unit 31 is equipped with a cooling coil 32 and a blower 33 inside the casing 34, and is configured to blow out into the communication equipment room R after adjusting the humidity with respect to the introduced outside air. Thereby, for example, it is possible to supply air having an indoor dew point temperature set value Ts. Therefore, the dry coil operation can always be performed by setting the set value of the evaporation temperature of the refrigerant of the cooling coils 14 and 15 of the local cooling device 12 to be several ° C higher than the indoor dew point temperature set value Ts. It becomes.

【0035】

The air-conditioning system according to the present embodiment is configured as described above, and the high-density exhaust heat from each rack L is cooled by the local cooling devices 12 installed in the aisle spaces 1 and 2. To. That is, when the blower 4 on the upper part of the rack L is operated, the low-temperature air-conditioned air from the local cooling device 12 flows into the casing 6 of the rack L from the opening 6a of the rack L and communicates stored in the rack L. The exhaust heat from the device 5 is processed and exhausted to the upper part of the rack L by the blower 4, and the exhausted high-temperature air is again sucked by the cross flow fan 16 through the cooling coils 14 and 15 of the local cooling device 12 and cooled. After that, it is blown out into the passage space 1 and circulates. Therefore, the static pressure of the cross flow fan 16 which is the blower of the local cooling device 12 is expected to be mainly the pressure loss in the cooling coils 14 and 15, and the static pressure of the blower 4 functioning as the ventilation fan at the upper part of the rack L is mainly. The capacity should be set in anticipation of the pressure loss in the rack L.

【0036】

In the present embodiment, the heat exhaust from the rack L discharged from the blower 4 at the upper part of the rack L is cooled for a part (most) of the heat exhaust, and most of the cold air descends in the passage space, and one The portion (mostly) is returned into the rack L through the opening 6a and the rest is led to the underfloor chamber 7. The high-temperature exhaust that stays near the ceiling is exhausted to the outside by an exhaust fan (not shown) installed in the communication equipment room R, which corresponds to the amount of air supplied by the outside air processing unit 31. If the rack L is provided with an opening on the passage space side, the underfloor chamber 7 itself as an air passage is unnecessary, and the floor height can be kept low. In that case, the opening 8 at the bottom of the rack L is closed.

【0037】

In this way, the high-density heat generated from the rack L is efficiently processed by the local air circulation by the local cooling device 12, so that it is compared with the conventional technique that relies on the blowout from the underfloor chamber. The overall ventilation energy is reduced. Further, there is no variation in the cooling capacity with respect to the rack L due to the flat air volume distribution in the underfloor chamber 7.

【0038】

Moreover, since the local cooling device 12 responsible for such processing is installed in the space above the passage spaces 1 and 2 formed between the racks L, it is possible to reduce the floor area of the communication equipment room R. The rentable ratio is higher than before. In addition, even if racks are added, local cooling devices 12 can be installed in sequence, and even if the local heat load in the room increases due to the addition of communication equipment, the local cooling devices 12 can be added. It is possible to respond by controlling the capacity of other local cooling devices 12 nearby.

【0039】

Further, since the cooling coils 14 and 15 of the local cooling device 12 use direct expansion coils using a refrigerant, there is no danger of water leakage or the like. Moreover, since the refrigerant evaporation temperature at the cooling coils 14 and 15 is controlled higher than the dew point temperature of the treated air to operate as a so-called dry coil, the communication device 5 is prevented from getting wet and the cooling coils 14 and 15 are used. There is no waste that the humidity is reduced and the amount of humidification increases accordingly.

【0040】

In the configuration shown in FIG. 2, the local cooling devices 12 are installed at intervals along the longitudinal direction of the rack row, but the rack in the thinned position also functions as a ventilation fan installed above it. Since the cold air is sucked into the inside from the opening 6a of the rack L by the operation of the blower 4, the cooling effect is not hindered.

【0041】

Of course, it is possible to air-condition the communication equipment room with a higher heat generation density by using it together with the conventional full-scale heat treatment type package air conditioner installed in the communication equipment room R or the air conditioner with a built-in chilled water coil.

【0042】

In addition, as shown in FIG. 2, the conditioned air from the local cooling device 12 is blown out from the opening 8 formed in the floor surface F of the other open space 3 through the opening 8 formed in the floor surface F. It is possible and contributes to the improvement of the temperature environment of the space part 3. Since this space portion 3 is an open space portion, in order to perform work such as wiring of a communication cable on the upper part of the rack L, the work may be performed in this space portion 3.

【0043】

In the above embodiment, only the upper part of the passage space 1 and 2 is covered with the top plate 11 and the local cooling device 12 itself to make the passage space 1 and 2 a more local space. However, as shown in FIG. Thus, if a hanging plate 51 is provided on the end faces of the aisle spaces 1 and 2 in the rack row direction to close the upper space inside the aisle spaces 1 and 2, cold air is released to the outside of the aisle space. Difficult and more efficient exhaust heat treatment can be performed.

【0044】

Furthermore, as shown in FIG. 7, if a wall surface 52 or a door body 53 that can be opened and closed is provided on the end faces of the aisle spaces 1 and 2 in the rack row direction, the aisle spaces 1 and 2 can be made into a closed space. It is possible to carry out more efficient exhaust heat treatment. In this case, in order for the worker to enter the passage space 1 and 2 and perform various maintenance work, a door body 53 is provided on at least one end face side of each passage space 1 and 2, and the door body 53 is opened and closed as appropriate. There is no problem in the work itself.

【0045】

Further, in the above-described embodiment, an opening 6a is formed on the opposite side surface of the casing 6 of the rack L so that the conditioned air from the local cooling device 12 is taken into the rack L. Such an opening 6a However, as shown in FIG. 8, an opening 61 leading to the underfloor chamber 7 may be formed on the floor surface F on the bottom surface of the rack L. In this case, the conditioned air from the local cooling device 12 is taken into the rack L from the opening 8 through the underfloor chamber 7 and the opening 61. In this case, the underfloor chamber 7 forms a part of the flow path of the conditioned air, but since the distance is short, the blowing energy is reduced as compared with the conventional case.

【0046】

Further, the airflow control plate 62 may be installed above the open space portion 3. In the present invention, although the air is to be circulated locally, the amount of air discharged from the rack L is very large because a large sensible heat load is processed. Therefore, since the high temperature air discharged from the upper part of the rack L circulates in the entire communication equipment room R, the room temperature in the maintenance area of the open space 3 may rise considerably. The airflow control plate 62 is installed for the purpose of reducing air mixing in the maintenance area due to high temperature air. By installing this airflow control plate 62 from the ceiling or rack L via an appropriate support member, facing the opening 8 provided on the floor and leaving a gap as an air passage above the rack L. The low-temperature air blown out from the opening 8 of the floor surface F of the space 3 is difficult to diffuse, and stays in the open space 3 to form a temperature stratification. The environment can be improved.

【0047】

The example shown in Fig. 9 shows an air conditioning system that can handle higher density sensible heat loads in combination with other cooling devices. That is, in the air conditioning system shown in FIG. 9, the conventionally used full-scale heat treatment type package air conditioner 71 and the chilled water coil 72 are arranged in series to enable large temperature difference cooling.

【0048】

In the system of FIG. 9, cold water from the refrigerator 73 and the cooling tower 74, and air treated by the cold water coil 72 using the cooling water as a heat source are further treated by the full-scale heat treatment type package air conditioner 71 to perform lower temperature air conditioning. Air is supplied to the underfloor chamber 7 and blown out from the openings 8 and 61 on the floor surface. According to such an air conditioning system, it is possible to carry out large temperature difference cooling, so that the total amount of air blown can be further reduced. Further, since the type of heat source is different between the full-scale heat treatment type package air conditioner 71 and the chilled water coil 72, even if one of them is stopped, all the air conditioning for the communication equipment room R is not stopped. Further, as another cooling device, an air conditioner having a built-in chilled water coil may be used.

【0049】

The example shown in FIG. 10 shows another example for causing the dry coil operation of the local cooling device 12. In this example, the indoor air conditioner 81 is separately installed in the communication equipment room R in addition to the outside air processing unit 31. Further, the air supply from the outside air processing unit 31 and the air supply from the indoor air conditioner 81 are each blown into the underfloor chamber 7. In this indoor air conditioner 81, indoor air is sucked by a fan 83, processed by a cooling coil 82, and blown into the underfloor chamber 7. An exhaust fan 84 is provided near the ceiling in the communication equipment room R.

【0050】

Next, an example of the control will be described. The outside air OA introduced into the communication equipment room R is supplied after being adjusted (humidified or humidified) to the set dew point temperature Ts of the room air by the outside air processing unit 31. Therefore, when the steady state is reached, the dew point temperature of the indoor atmosphere becomes Ts. Here, the evaporation temperature Tev of the direct expansion type cooling coils 14 and 15 of the local cooling device 12 is set several ° C ( T2) higher than the set dew point temperature Ts (Tev = Ts + T2) for local cooling. The direct expansion type cooling coils 14 and 15 of the device 12 can carry out dry coil operation.

【0051】

However, if the outside air processing unit 31 breaks down, or if high humidity outside air enters the room from another route and the dew point temperature of the room air rises, dew condensation will occur on the cooling coils 14 and 15 of the local cooling device 12. It may occur.

【0052】

In order to prevent such a situation, for example, when the cooling coil 82 of the indoor air conditioner 81 is a direct expansion type, the refrigerant evaporation temperature is set, and in the case of a chilled water coil, the water temperature of the supplied cold water is set directly to the local cooling device 12. It may be set lower than the refrigerant evaporation temperature Tev of the inflatable cooling coils 14 and 15. That is, the refrigerant evaporation temperature of the cooling coil 82 of the indoor air conditioner 81 (in the case of the chilled water coil, the water temperature of the supplied chilled water) Ta is set to Ta = Ts + T1 so that the relationship is 0 < T1 < T2. T1 should be set and set. As a result, the surface of the cooling coil 82 of the indoor air conditioner 81 condenses first to perform the dehumidification operation, so that it is possible to suppress an increase in the dew point temperature of the indoor air.

【0053】

The following example can be proposed as an operation example of the indoor air conditioner 81. The indoor air conditioner 81 is operated only when the dew point temperature of the indoor air rises. Even during normal operation, the indoor air conditioner 81 is operated for air conditioning in the communication equipment room R, and the dehumidification operation is performed only when the dew point temperature of the indoor air rises.

【0054】

In addition to the example shown in FIG. 3, the configuration of the local cooling device 12 that supplies cold air to the passage space 1 and 2 is, for example, local cooling in which a pressure fan is integrated on the downstream side (passage space side) of the cooling coil. The device may be used. Such local cooling devices may be arranged so that the tops of the local cooling devices are in contact with each other, for example, as a set of two so that the devices face each other diagonally. Further, such an integrated local cooling device may be installed on substantially the same plane as the top plate surface.

【0055】

Further, the above-mentioned outside air processing unit 31 and indoor air conditioner 81 are packaged air conditioner type and exemplify the lower blowout type, but downward (in the case of an outside air conditioner, from the outer wall to the lower back side of the circulation air conditioner). In some cases, an air suction port may be provided (below the front surface) so that the cooled air can be blown out from above (upper front surface).

【0056】

[Effect of the invention]

According to the present invention, it is possible to carry out appropriate exhaust heat treatment under space-saving and energy-saving in a facility having high-density exhaust heat from a communication device.

[Simple explanation of drawings]

[Figure 1]

It is explanatory drawing which shows the outline of the communication equipment room to which the air-conditioning system which concerns on 1st Embodiment of this invention is applied.

[Figure 2]

It is explanatory drawing which shows the state for taking conditioned air into a rack in the conditioned system which concerns on 1st Embodiment of this invention.

[Fig. 3]

It is explanatory drawing of the local cooling system in the air-conditioning system of FIG.

[Fig. 4]

It is explanatory drawing which shows the outline of the temperature control of the air-conditioning system which concerns on 1st Embodiment of this invention.

[Fig. 5]

It is explanatory drawing which shows the outline of another temperature control applicable to the air-conditioning system which concerns on 1st Embodiment of this invention.

[Fig. 6]

It is explanatory drawing which shows the outline of the communication equipment room to which the air-conditioning system which concerns on 2nd Embodiment of this invention is applied.

[Fig. 7]

It is explanatory drawing which shows the outline of the communication equipment room to which the air-conditioning system which concerns on 3rd Embodiment of this invention is applied.

[Fig. 8]

It is explanatory drawing which shows the outline of the structure of the air-conditioning system of another form which takes in air-conditioning air into a rack.

[Fig. 9]

It is explanatory drawing which shows the outline of the structure of the air-conditioning system which concerns on embodiment of this invention which combined with other cooling devices.

[Fig. 10]

It is explanatory drawing which shows the outline of the structure of the air conditioning system which has an indoor air conditioner separately.

[Fig. 11]

It is explanatory drawing of the prior art.

[Fig. 12]

It is a perspective view which shows the outline of a communication equipment room.

[Explanation of symbols]

1,2 Aisle space 3 Space 4 Blower (ventilation fan) 5 Communication equipment 6 Casing 6a opening 7 Underfloor chamber 8 openings 12 Local cooling device 14,15 Cooling coil 16 Cross flow fan 17 Outdoor unit 21 Control unit 22 Temperature sensor 31 Outside air processing unit F floor L rack L1 ~ L4 rack row R Communication Equipment Room