JPH0810073B2 - Air conditioner - Google Patents

Description

TECHNICAL FIELD The present invention relates to an air conditioner capable of switching from refrigeration cycle cooling to cooling water cooling using cooling water cooled by the outside air according to the outside air temperature. .

[Conventional technology]

A conventional air conditioner of this type is constructed as shown in FIG.

FIG. 4 is a schematic configuration diagram showing a conventional air conditioner for a computer room. In FIG. 4, 1 is an air conditioner main body, 2 is an air suction port, and a filter 3 is arranged inside the air suction port 2. It is set up. An air conditioning air outlet 4 is provided below the air conditioner body 1 and forms an air passage 5.
6 is a cooler as a heat exchanger used in refrigeration cycle cooling, 7 is a reheater consisting of a water coil type heat exchanger through which cooling water described later is passed, and these coolers are provided in the air passage 5. 6,
A reheater 7 is provided, and a blower 8 that sends air to the conditioned air outlet 4 is provided. 9 is a condenser, 10
Is a compressor, which is connected to the cooler 6 through a common pipe (not shown) to form a refrigeration cycle. 11 is a cooling tower,
A cooling water pipe 12 connects the cooling tower 11 and the condenser in communication with each other, and a proportional control type three-way valve for cooling water is provided on the outlet pipe 13 side of the cooling tower 11.
14 and pump 15 are mounted in series. Reference numeral 16 denotes a reheat proportional control type three-way valve disposed on the reheater 7 side, one for the reheater 7, the other for the reheater 7 and the condenser 9, and the other for the cooling tower 11 Is connected to the inlet side 17 of the container by a cold water pipe 18. 19 is the proportional control three-way valve for the cooling water 14
And a cold water pipe 18, which communicates with the cold water pipe 18, 20 and 21 are proportional water temperature setting devices for cooling water for detecting the cooling water outlet temperature from the cooling tower 11 and controlling the proportional control type three-way valve 14 for cooling water. And, it is arranged on the pump 15 side of the cold water pipe 12. 22 is a cooling tower
11-side relay box with the proportional control type three-way valve for cooling water
It is provided with a contact 23 for switching the proportional water temperature setting devices 20 and 21 for cooling water for controlling the cooling water 14. Reference numeral 24 denotes an outside air temperature sensor for detecting the outside air temperature. The outside air temperature sensor 24 is provided near the cooling tower 11 and is connected to the relay box 22. 25 is a cooling water cooling switching thermostat (cooling water / water temperature setting device) for detecting the cooling water outlet temperature and switching from the refrigeration cycle cooling operation by the compressor 10 to the cooling water cooling operation by the cold water obtained in the cooling tower 11. Is a relay box on the side of the main body of the air conditioner, equipped with a contact 29 for switching between reheat proportional control type temperature setters 27 and 28 for detecting an error in the temperature of air blown into the free access floor, and the reheat proportional control. It is connected to the three-way valve 16 and controls it. Reference numeral 30 is a connecting wire for electrically connecting the compressor 10, the main body 1 side relay box 26, the cooling / water cooling switching thermostat 25, the outside air temperature sensor 24, and the cooling tower 11 side relay box 22 via relays 31 and 32. ing. 33 is a humidifier, which is electrically connected to the humidity controller 34.

Next, the operation of the air conditioner configured as described above will be described. First, the room air first passes from the air suction port 2 through the filter 3, reaches the cooler 6 along the air passage 5, and is cooled and dehumidified, After passing through the reheater 7 and being reheated to a predetermined temperature, the blower 8 blows the air from the conditioned air outlet 4 to the outside of the air conditioner body 1.

In the summer or when the indoor load is large, the compressor 10 and the blower 8 and the cooling tower 11 are operated in the same manner as an ordinary air conditioner, and the cooler 6 cools and dehumidifies. At this time, the cooling water from the cooling tower 11 is controlled by the proportional water temperature setting device 20 for cooling water such that the opening / closing degree of the proportional control type three-way valve for cooling water 14 is adjusted to about 30 ° C. For example, when the cooling water outlet temperature is higher than the set temperature, the opening degree of the cooling water proportional control type three-way valve 14 is adjusted to the opening direction, and when it is low, the flow rate is adjusted. Then, heat is exchanged through the condenser 9 to become hot water of about 37 ° C., and the hot water is reheated through the reheater 7 to make the blast temperature constant. The temperature control of the reheater 7 is performed by adjusting the opening / closing degree of the reheat proportional control type three-way valve 16 through the reheating proportional control type temperature setting device 27 for detecting the blowout temperature error in the free access floor. For example, when the blowout temperature is higher than the set temperature, the opening degree of the reheat proportional control type three-way valve 16 is adjusted so as to be reduced, and when it is low, the opening direction is adjusted.

In the winter, cold water is obtained from the cooling tower 11, so cold water cooling is performed. At this time, the compressor 10 is stopped to stop the flow of the refrigerant in the refrigeration cycle. When the outside air temperature is low, the outside air temperature sensor 24 switches the contacts in the relay box 22 on the cooling tower 11 side and disconnects the contacts in the relay 31. In addition, the chilled water circulated from the cooling tower is controlled by adjusting the opening / closing degree of the proportional control type three-way valve for cooling water so that the chilled water proportional type water temperature setter 21 reaches approximately 10 ° C. If the set temperature is 10 ° C. or less by the touch 25, the contact of the relay 32 is cut off, the compressor 10 is not electrically connected and the compressor 10 is stopped, and the contact 29 of the relay box 26 on the air conditioner body 1 side is switched. . The cold water passes through the condenser 9 and is passed to the reheater 7 in a low temperature state. At this time, the reheater 7 is used as a heat exchanger for cold water. The blowout temperature is controlled by adjusting the opening / closing degree of the reheat proportional control type three-way valve 16 through a reheat proportional control type temperature setter 28 which detects a blowout temperature error in the free access floor. For example, if the outlet temperature is higher than the set temperature, adjust the opening degree of the reheat proportional control type three-way valve 16 to open,
If it is low, adjust to the direction of squeezing. Humidifier 33 is a humidity controller 34
Is activated and deactivated, and the humidity of the conditioned air is adjusted accordingly.

Therefore, the ON-OFF signal of the compressor 10 is transmitted to the relay box 22 on the cooling tower 11 side and the relay box 26 on the air conditioner body 1 side by the connecting electric wire 30 in summer, when there is a lot of indoor load, and in winter. In the case of cold water cooling using outside temperature, reheat operation and cold water cooling operation are automatically performed.

[Problems to be Solved by the Invention]

However, in the conventional air conditioner thus configured, the temperature of the cooling water supplied to the condenser 9 through the cold water pipe 12 is 10 to 10 during the refrigeration cycle cooling operation before the cold water cooling operation switching in winter. Since it is as low as 15 ° C, the temperature of the refrigerant will drop excessively. As a result, the evaporation temperature when the refrigerant evaporates in the cooler 6 is too low, the cooler 6 is excessively cooled, and dew condensation may occur on the surface of the cooler 6.

When the operation is switched to the cold water cooling operation in the state in which dew condensation has occurred, the supply of the refrigerant to the cooler 6 is stopped and the temperature of the cooler 6 rises, so that the moisture adhering to the cooler 6 evaporates. There arises a problem that the humidity of the air temporarily rises. In order to eliminate such a problem, the cooling water temperature may be warmed up to about 15 ° C. in order to suppress the decrease in the evaporation temperature of the refrigerant, but this is uneconomical.

[Means for solving the problem]

An air conditioner according to the present invention is a compressor for a refrigeration cycle, which is compressed by a compressor, and a refrigerant condensed by a condenser cooled by cooling water cooled by outside air is supplied through an expansion valve, A cooling water cooling reheater cooled by cooling water supplied to the condenser, and a humidifier are arranged in the air passage,
In an air conditioner that switches a refrigeration cycle using the cooler and a cold water cooler that supplies cold water to the reheater in a state in which a compressor is stopped in accordance with the outside air temperature, cooling water to the condenser. The cold water pipe to be supplied is provided with a water control valve that is controlled to open and close so as to be closed when the compressor is stopped, and the upstream side of the water control valve in this cold water pipe is closed and compressed when the compressor is operating. The refrigerant inlet pipe of the condenser is stopped by connecting it to the cooling water inlet side of the reheater through a cooling water bypass pipe in which a cooling water bypass valve that is opened when the machine is stopped is provided. The humidifier is kept constant before and after the compressor is stopped by communicating with the refrigerant inlet pipe of the cooler through a refrigerant bypass pipe in which a bypass solenoid valve that has been opened for a certain period of time and closed at other times is interposed. Stop for hours It is obtained by the structure.

[Action]

By controlling the amount of cooling water in the condenser by the water control valve, it is possible to suppress the decrease in the evaporation temperature of the refrigerant in the heat exchanger during the refrigeration cycle cooling operation in winter, and to open the bypass solenoid valve. As a result, the capacity of the heat exchanger is controlled by the hot gas bypass, and the decrease in the evaporation temperature of the refrigerant is suppressed. Furthermore, by opening the cooling water bypass valve, the cooling water is not directly heated by the condenser but is directly guided to the reheater, which improves the cooling effect, and by temporarily stopping the humidifier. Humidity rise at the time of operation switching can be suppressed low.

〔Example〕

Hereinafter, the configuration and the like will be described in detail with reference to the embodiments shown in the drawings.

FIG. 1 is a schematic configuration diagram of an air conditioner of the present invention, FIG. 2 is a refrigerant piping system diagram of the air conditioner of the present invention, and FIG. 3 is a flow chart of a control program at the time of switching between cooling and cooling. In these figures, the same or equivalent members as those described in FIG. 4 are designated by the same reference numerals, and detailed description thereof will be omitted here. In these figures, 41 is a water control valve for adjusting the amount of cooling water supplied to the condenser 9, and this water control valve 41 is a three-way valve whose main flow path side is connected to the cooling water inlet side pipe 9a of the condenser 9. The relief side flow path is a condenser 9
Is connected to the cooling water outlet side pipe 9b. That is, the amount of cooling water supplied to the condenser 9 is adjusted by adjusting the opening / closing degree of the water control valve 41. 42 is a cooling water bypass valve, and this cooling water bypass valve 42 is an electric two-way valve, and is a water control valve in the cooling water inlet side pipe 9a of the condenser 9.
It is provided in a cooling water bypass pipe 43 that connects the upstream side of 41 with the reheater 7 inlet side pipe 7a, receives the ON-OFF signal of the compressor 10 via the relays 31, 32 and the relay 44, and Is opened and closed.

45 is a bypass solenoid valve, and this bypass solenoid valve 45 is the second
As shown in the figure, it is provided in a refrigerant bypass pipe 46 that connects the refrigerant inlet pipe 9c of the condenser 9 and the refrigerant inlet pipe 6a of the cooler 6, and is connected to a timer (not shown) as a control device for operation. It is configured to be opened for a certain period of time before the compressor is stopped during switching. Further, the humidifier 33 is connected to the timer, and immediately after the compressor is stopped, it is stopped for a certain period of time. In addition, 47 in FIG. 2 is a muffler,
48 is a stray, 49 is an expansion valve, 50 is a distributor, 51 is an expansion valve temperature sensing tube, 52 is an expansion valve equalizing pipe, 53 is an accumulator, 54 is a pressure switch, 55 is a pressure gauge, and an air conditioner Two piping systems are provided in one unit of the main body.

 Next, the operation of the air conditioner of the present invention will be described.

The operation of each part at the time of switching from the compressor operation in the summer or when the indoor load is large and the compressor operation in the winter to the cold water cooling operation is the same as the conventional one.

During the refrigeration cycle cooling operation before switching to the cold water cooling operation in winter, the cooling water circulated from the cooling tower 11 is controlled by the cooling water proportional water temperature setting device 21 to about 10 ° C. by the cooling water proportional control type three-way valve 14. It is controlled by adjusting the degree of opening and closing. on the other hand,
When the cooling water temperature decreases, the evaporation temperature of the refrigerant decreases, and the condensation pressure decreases, the cooling water temperature of the condenser 9 is throttled by the water control valve 41 to maintain the condensation pressure at a predetermined pressure. The drop is prevented. At this time, the contacts of the relays 31 and 32 are closed, the contacts of the relay 44 are open, and the cooling water bypass valve 42 is closed during the operation of the compressor. If the cooling water temperature detected by the cooling water cooling switching thermostat 25 is 10 ° C. or less, the contact of the relay 32 is broken and a command for the cooling water cooling operation is issued, and the timer is set as shown in step P1 in FIG. Start counting. After 210 seconds have elapsed as shown in step P2 after the start of counting, the compressor 10 is stopped in step P3.

In Step P3, as the compressor 10 stops,
The reheat proportional control three-way valve 16 is switched so that the entire amount of cooling water passes through the reheater 7, and the water control valve 41 is closed.
At the same time, the contact of the relay 44 is closed and the cooling water bypass valve 42 is opened. As a result, the cooling water passes from the cooling water pipe 12 through the cooling water bypass pipe 43, bypasses the condenser 9, and flows to the reheater 7. That is, the cooling water is passed through the reheater 7 without being warmed by the condenser 9, and the air is quickly cooled to perform the cold water cooling operation.

In addition, the compressor 10
The capacity of the cooler 6 is controlled by the hot gas bypass for 210 seconds until the stop of the cooling. This will be described in detail. First, the bypass solenoid valve 45 of one of the two refrigeration cycles (hereinafter, this system is referred to as the A system).
(This is indicated by 45a in FIG. 3), but as shown in steps P4 to P5 in FIG.
It is energized for 120 seconds and opened. Bypass solenoid valve 45a
While is open, the high-temperature and high-pressure refrigerant flowing into the condenser 9 of the A system flows through the refrigerant bypass pipe 46 and the bypass solenoid valve 45a to the refrigerant inlet pipe 6a without passing through the condenser 9. That is, hot gas (not shown) is bypassed to the cooler 6 to control the capacity.

After 120 seconds have passed, in step P6, the bypass solenoid valve 45a of the A system is de-energized and closed, and the bypass solenoid valve 45b of the other system B system is energized and opened. By opening the bypass solenoid valve 45b, hot gas is bypassed to the cooler 6 of the B system, and capacity control is performed. Then, 90 seconds later, that is, 210 seconds after the timer starts counting (step P1), the bypass solenoid valve 45b is de-energized and closed (step P3).

Further, after 150 seconds have elapsed since the timer started counting in step P1, the humidifier 33 is stopped as shown in steps P7 to P8, and as shown in steps P9 to P10 when 220 seconds have elapsed from step P1. The humidifier 33 is driven. That is, even if the humidification signal from the humidity controller 34 is received for 60 seconds before the compressor 10 is stopped and switched to the cold water cooling operation and for 10 seconds after the switching, the refrigeration by the compressor operation is stopped. It prevents the humidity from rising when switching from cycle cooling to cold water cooling operation.

As described above, after the compressor 10 is stopped in step P3 and shifts to the cold water cooling operation, if the blowout temperature is lower than the set temperature, the opening degree of the reheat proportional control type three-way valve 16 is reduced as in the conventional case. Direction (steps P11 to P12), and if the temperature is higher than the set temperature, the opening of the three-way valve 16 is adjusted to open (steps P11 to P13).

〔The invention's effect〕

As described above, according to the present invention, a refrigeration cycle cooling cooler in which the refrigerant compressed by the compressor and condensed by the condenser cooled by the cooling water cooled by the outside air is supplied through the expansion valve. A cooling water cooling reheater that is cooled by the cooling water supplied to the condenser, and a humidifier are provided in the air passage, and the refrigeration cycle cooling using the cooler and the compressor are stopped. In an air conditioner that switches between cold water cooling that supplies cold water to the reheater according to the outside air temperature in a closed state, a cold water pipe that supplies cooling water to the condenser becomes a closed state when the compressor stops. A cooling water bypass valve that is controlled to open and close is installed, and a cooling water bypass valve that is closed on the upstream side of the cooling water valve in the cold water pipe when the compressor is operating and that is open when the compressor is stopped is installed. Via the cooling water bypass pipe The refrigerant inlet pipe of the condenser, the refrigerant inlet pipe of the condenser is opened via a refrigerant bypass pipe having a bypass solenoid valve that is opened for a certain time before the compressor is stopped and closed at other times. Since the humidifier is connected to the refrigerant inlet pipe of the cooler and the humidifier is stopped for a certain period of time before and after the compressor is stopped, when the refrigeration cycle cooling operation is switched to the cold water cooling operation and before the compressor is stopped. , The hot gas bypassing the condenser is supplied to the cooler and the cooler temperature rises,
The cooler can be in a state with little condensation. At this time, since the cooling water amount of the condenser is controlled by the water control valve, it is possible to suppress the decrease in the evaporation temperature of the refrigerant, and thus it is possible to reduce the dew condensation that occurs in the cooler.

With this, it is possible to prevent the humidity from rapidly increasing due to the evaporation of the water adhering to the surface of the cooler after switching to the cold water cooling operation. Further, even if the temperature of the cooler rises in this way, since the cooling water bypassing the condenser is supplied to the reheater after the compressor is stopped, a high cooling effect can be secured. . further,
Since the humidifier is also stopped when the operation is switched, the increase in humidity is further reduced.

Therefore, the increase in humidity when switching to the cold water cooling operation can be suppressed within an allowable range, and since the cooling water is directly supplied to the reheater, the cooling water temperature can be lowered to about 11 ° C. Therefore, there is also an effect that the dehumidifying effect during the cold water cooling operation can be improved.

[Brief description of drawings]

1 is a schematic configuration diagram of an air conditioner of the present invention, FIG. 2 is a refrigerant piping system diagram of the air conditioner of the present invention, FIG. 3 is a flow chart of a control program at the time of switching between cooling and cooling, and FIG.
FIG. 1 is a schematic configuration diagram showing a conventional air conditioner for a computer room. 1 ... Air conditioner body, 6 ... Cooler, 7 ... Reheater,
7a …… Reheater inlet side piping, 9 …… Condenser, 9a …… Cooling water inlet side piping, 9b …… Cooling water outlet side piping, 9c …… Refrigerant inlet tube, 10 …… Compressor, 41 …… Water control valve, 42 …… Cooling water bypass valve, 43 …… Cooling water bypass pipe, 45 …… Bypass solenoid valve.

Claims (1)

[Claims] 1. A refrigeration cycle cooling cooler to which a refrigerant compressed by a compressor and condensed by a condenser cooled by cooling water cooled by outside air is supplied through an expansion valve, and the condenser. A cooling water cooling reheater that is cooled by the supplied cooling water, and a humidifier are provided in the air passage, and a refrigeration cycle cooling system that uses the cooling device, and the reheating with the compressor stopped. In an air conditioner that switches between cold water cooling that supplies cold water to a condenser according to the outside air temperature, a cold water pipe that supplies cooling water to the condenser is controlled to open and close so as to be closed when the compressor is stopped. A cooling water bypass pipe in which a cooling water bypass valve is provided, and an upstream side of the cooling water valve in the cooling water pipe is closed when the compressor is operating and is opened when the compressor is stopped. Through the cooling water inlet side of the reheater. Is, the refrigerant inlet pipe of the condenser,
The compressor is opened for a certain period of time before the compressor is stopped, and is communicated with the refrigerant inlet pipe of the cooler via a refrigerant bypass pipe in which a bypass solenoid valve that is closed at other times is interposed, and the humidifier is An air conditioner characterized by a structure in which it is stopped for a certain period of time both front and rear.