JP2004353893A - Air conditioner having variable sensible heat ratio - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air conditioner having a variable sensible heat ratio for allowing the flow rate of refrigerant flowing between a precooler and a reheater, achieving an energy saving air-conditioning system free of useless cooling or dehumidification. <P>SOLUTION: The air conditioner comprises an air cooler 12 for cooling treated air, the precooler 11 for precooling the treated air with the evaporation of refrigerant before cooling it with the air cooler 12, the reheater 13 for heating the treated air with the condensation of the refrigerant after cooling it with the air cooler 12, a first refrigerant passage 21 for feeding the condensed refrigerant from the reheater 13 to the precooler 11, and a second refrigerant passage 22 for feeding the evaporated refrigerant from the precooler 11 to the reheater 13. An on-off valve 14 is provided in the first refrigerant passage 21 or the second refrigerant passage 22 for controlling the flow rate of the refrigerant. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an air conditioner having a variable sensible heat ratio, and more particularly to an air conditioner having a precooler and a reheater and having a variable sensible heat ratio.
[0002]
[Prior art]
Conventionally, as shown in FIG. 6, an air conditioner provided with a pre-cooling coil 1 and a reheating coil 3 provided with a main cooling coil 2 interposed therebetween in order to reduce a sensible heat ratio along a flow of processing air. (For example, see Patent Document 1). In this air conditioner, the pre-cooling coil 1 and the re-heating coil 3 are configured as a so-called heat pipe, and the refrigerant liquid condensed in the re-heating coil 3 is introduced to the pre-cooling coil 1 and the refrigerant evaporated in the pre-cooling coil 1 A refrigerant gas pipe 5 for guiding the gas to the reheating coil 3 was provided. Cold water is supplied to the main cooling coil 2 from the heat source unit 31.
[0003]
[Patent Document 1]
US Pat. No. 4,607,498 (FIG. 3)
[0004]
[Problems to be solved by the invention]
However, in the conventional air conditioners described above, the sensible heat ratio cannot be increased, and when an air conditioning load having a large sensible heat load is generated, excess dehumidification occurs and an extra heat load is transmitted to the heat source device. Therefore, there is a problem that the energy consumption of the system is unnecessarily increased.
[0005]
Therefore, an object of the present invention is to provide an air conditioner having a variable sensible heat ratio.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, an air conditioner according to the first aspect of the present invention includes, as shown in FIG. 1, an air cooler 12 for cooling process air; A pre-cooler 11 for pre-cooling the refrigerant by evaporation; a re-heater 13 for cooling the processing air by an air cooler 12 and then heating the refrigerant by condensing the refrigerant; re-heating the condensed refrigerant. A first refrigerant path 21 for sending the evaporated refrigerant from the pre-cooler 11 to the reheater 13; a first refrigerant path 21 for sending the evaporated refrigerant from the pre-cooler 11 to the reheater 13; The on-off valve 14 for adjusting the flow rate of the refrigerant is provided in the second refrigerant path 22.
[0007]
With this configuration, since the on-off valve for adjusting the flow rate of the refrigerant is provided in the first refrigerant path 21 or the second refrigerant path 22, the flow rate of the refrigerant flowing between the precooler and the reheater is changed. be able to. Changing the refrigerant flow rate is a concept that includes the case where the flow of the refrigerant is interrupted. Increasing the flow rate of the refrigerant increases the amount of refrigerant evaporated in the precooler and condensed in the reheater. Therefore, the amount of dehumidification increases, and the sensible heat ratio of the air conditioner decreases. If the flow rate of the refrigerant is reduced, the sensible heat ratio increases.
[0008]
As described in claim 2, in the air conditioner according to claim 1, the first refrigerant path 21 is provided vertically below the pre-cooler 11 and the reheater 13, and The refrigerant path 22 is provided vertically above the pre-cooler and the reheater, and the open / close valve 14 is provided in the first refrigerant path 21.
[0009]
With this configuration, the first refrigerant path is provided vertically below the pre-cooler and the reheater, and the second refrigerant path is positioned relative to the pre-cooler and the reheater. Since it is provided vertically upward, the refrigerant liquid tends to flow in the first refrigerant path. Further, since the on-off valve is provided in the first refrigerant path, the on-off valve can open and close the path of the refrigerant liquid, and can effectively adjust or shut off the refrigerant flow rate. Moreover, the diameter of the on-off valve can be reduced.
[0010]
Further, as described in claim 3, in the air conditioner according to claim 1 or 2, the humidity detector 15 that detects the humidity of the processing air, and receives the detection signal of the humidity detector 15, A controller 17 is provided for controlling the opening and closing of the on-off valve 14 according to the humidity of the processing air.
[0011]
The humidity detector typically detects the humidity of the treated air before being precooled by the precooler. Further, a temperature detector may be provided, and the controller may receive the detection signal of the temperature detector and open and close the on-off valve based on the humidity and the temperature.
[0012]
With this configuration, since the controller is provided, the opening and closing of the on-off valve can be controlled to automatically perform the cooling operation, the switching from the cooling operation to the dehumidifying operation, and the switching from the dehumidifying operation to the cooling operation.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each of the drawings, the same or corresponding members are denoted by the same or similar reference numerals, and redundant description will be omitted.
[0014]
FIG. 1 is a flowchart of an air conditioner 10 according to a first embodiment of the present invention. The air conditioner 10 is an air conditioner capable of operating in a dehumidifying mode in which the processing air is cooled to its dew point temperature to remove moisture, and then reheated and dehumidified, and in a cooling mode in which mainly sensible heat is removed.
[0015]
Here, when "the processing air is cooled to the dew point temperature and dehumidified", the processing air may be slightly supercooled, and in this case, "cooled to the dew point temperature or less and dehumidified". Shall be included. In addition, air cooled to the dew point temperature to remove moisture has a lower dew point temperature than the original air, so `` cooling below the dew point temperature and dehumidifying '' based on the initial dew point temperature, this concept Including.
[0016]
The configuration of an air conditioner 10 according to an embodiment of the present invention will be described with reference to FIG. The air conditioner 10 dehumidifies or cools processing air supplied into an air conditioning space 100 (not shown) for cooling.
[0017]
The air conditioner 10 cools return air from an air conditioning space as processing air with cold water supplied from a chiller 31 as a heat source device, and a main coil 12 as an air cooler and an upstream of the main coil 12 as processing air. And a reheat coil 13 as a reheater for reheating the processing air downstream of the main coil 12.
The structures of the pre-cooling coil 11 and the reheating coil 13 will be described later in detail with reference to another drawing.
[0018]
FIG. 1 (also FIGS. 3 and 4) is a schematic side view of the air conditioner 10 as viewed from the side. That is, as a side view, the vertical relationship among the pre-cooling coil 11, the main coil 12, and the reheating coil 13 is shown. As illustrated, the pre-cooling coil 11, the main coil 12, and the reheating coil 13 are arranged in a substantially horizontal direction.
[0019]
The lowermost part of the narrow tube of the pre-cooling coil 11 and the lowermost part of the reheating coil 13 are connected and communicate with each other by a first refrigerant path 21. The uppermost part of the pre-cooling coil 11 and the uppermost part of the reheat coil 13 are connected and communicate with each other by a second refrigerant path 22. FIG. 1 is a side view showing the vertical relationship between the first refrigerant path 21 and the second refrigerant path 22. That is, as shown in the drawing, the first refrigerant path 21 and the second refrigerant path 22 are disposed vertically below and above the precooling coil 11, the main coil 12, and the reheating coil 13, respectively. In such a configuration, the refrigerant is sealed in the precooling coil 11 and the reheating coil 13. The enclosed refrigerant circulates between the precooling coil 11 and the reheating coil 13 through the first refrigerant path 21 and the second refrigerant path 22 to operate as a so-called heat pipe.
[0020]
Here, when the pre-cooling coil 11 and the re-heating coil 13 act as a heat pipe, the refrigerant liquid condensed in the re-heating coil 13 flows to the pre-cooling coil 11 through the first refrigerant path 21, and The evaporated refrigerant gas flows to the reheating coil 13 through the second refrigerant path 22.
[0021]
An electromagnetic valve 14 as an on-off valve is inserted and arranged in the first refrigerant path 21. In addition, a humidity sensor 15 as a humidity detector and an air temperature sensor 16 as a temperature detector are provided in the duct on the upstream side of the processing air of the precooling coil. These sensors only need to be able to detect the humidity and temperature of the processing air, and may be provided in an unillustrated air-conditioned space.
[0022]
The air conditioner 10 further includes a controller 17 that controls opening and closing of the electromagnetic valve 14. The controller 17 controls the opening and closing of the solenoid valves 15 and 16 depending on whether the air conditioner 10 is operated in the cooling mode or the dehumidification mode.
[0023]
A fan 18 for flowing processing air passing through the pre-cooling coil 11, the main coil 12, and the reheating coil 13 is provided in the processing air path. The processing air reheated by the reheating coil 13 and having a reduced relative humidity is sent to the air-conditioned space by the fan 18, and the return air from the air-conditioned space flows into the pre-cooling coil 11. The air conditioner assembly includes the pre-cooling coil 11, the main coil 12, the reheating coil 13, the pilot heat exchanger 14, the fan 18, and a housing for accommodating them.
[0024]
An example of the structure of the pre-cooling coil 11 and the reheating coil 13 will be described with reference to FIG. In this drawing, the pre-cooling coil 11 and the reheating coil 13 are extracted and shown. Actually, a main coil 12, which is an air cooler not shown in the figure, is provided between the two coils. The pre-cooling coil 11 and the reheating coil 13 are arranged in a substantially horizontal direction. The pre-cooling coil 11 and the reheating coil 13 are composed of multilayer fins 11a and 13a made of aluminum or the like, and a group of thin tubes penetrating the fins in a meandering manner.
[0025]
In this drawing, only a part of the fins of the pre-cooling coil 11 is shown, and other fins are omitted. In particular, the thin tube of the reheat coil 13 is configured so that the condensed refrigerant liquid flows down vertically without stagnation. In this figure, both the precooling coil 11 and the reheating coil 13 are configured as meandering thin tubes by connecting ends of a plurality of thin tubes arranged in a horizontal direction with U (U) tubes. The meandering thin tubes of each of the pre-cooling coil 11 and the reheating coil 13 are connected by a second refrigerant path 22 at the upper part. The meandering tubes of the pre-cooling coil 11 and the reheating coil 13 are connected by a first refrigerant path 21 at the lower part. The solenoid valve 14 is disposed in the first refrigerant path 21. In this drawing, the solenoid valve 14 is schematically illustrated.
[0026]
In such a structure, in the pre-cooling coil 11, the refrigerant liquid accumulated in the lower thin tube is heated by the processing air passing through the fin 11a, boiled and evaporated, and flows as a refrigerant gas into the upper thin tube. This refrigerant gas flows into the reheating coil 13 through the second refrigerant path 22, where it heats the processing air flowing through the fins 13a, where it is deprived of heat and condenses. The condensed refrigerant liquid accumulates in the lower part of the meandering thin tube. When the solenoid valve 14 is open, the coolant flows through the first coolant path 21 to the lower part of the precooling coil 11.
[0027]
The pre-cooling coil 11 only needs to have a structure in which the liquid-containing refrigerant gas smoothly flows from below to the upper side, and the reheating coil 13 may have a structure in which the gas-containing refrigerant liquid smoothly flows from the upper side to the lower side. Therefore, the present invention is not limited to the structure shown in FIG. 2, and may have a structure in which headers are provided at the uppermost portion and the lowermost portion in a horizontal direction, and the headers are connected by a plurality of thin tubes.
[0028]
Like the pre-cooling coil 11 and the reheating coil 13, the main coil 12 is also composed of a multilayer fin made of aluminum or the like and a group of thin tubes penetrating the fin in a meandering manner. In the embodiment of the present invention, since the main coil 12 uses cold water as a cooling medium, the arrangement of the thin tubes does not need to be the same as that of the precooling coil 11 and the reheating coil 13. A structure in which the upper and lower parts are arranged in a vertical direction and connected by U-tubes may be used.
[0029]
The operation of the air conditioner 10 according to the embodiment will be described with reference to the flowchart of FIG. This figure shows a case where the air conditioner 10 is set to the dehumidification mode.
[0030]
In the dehumidification mode, the solenoid valve 14 is opened by a command from the controller 17. In the figure, the white valves indicate that they are open.
[0031]
Since the solenoid valve 14 is open, the refrigerant liquid condensed in the reheat coil 13 and accumulated below the reheat coil 13 moves to the precooling coil 11 through the first refrigerant path 21. The refrigerant liquid moved to the precooling coil 11 evaporates in the precooling coil 11 to become a refrigerant gas, and the refrigerant gas moves to the reheating coil 13 through the second refrigerant path 22.
[0032]
In this way, the refrigerant exchanges heat between the processing air by repeating evaporation in the precooling coil 11 and condensation in the reheating coil 13. In other words, the refrigerant evaporates in the pre-cooling coil 11 and self-heats and evaporates by pre-cooling the high-temperature process air from the air-conditioned space. The evaporated refrigerant gas flows to the upper part of the reheat coil 13 through the second refrigerant path 22, condenses in the reheat coil 13, cools the main coil 12, and heats (reheats) the processing air whose temperature and absolute humidity have decreased. heat.
[0033]
The refrigerant liquid condensed in the reheating coil 13 passes through the first refrigerant path 21 and also passes through the electromagnetic valve 14 which is open, and flows into the lower part of the precooling coil 11. The flowing refrigerant evaporates in the pre-cooling coil 11 as described above. In this way, the pre-cooling coil 11 and the reheating coil 13 exchange heat between the processing air before and after the main coil 12. Since the pre-cooling coil 11 pre-cools the processing air, the main coil 12 can be effectively used to lower the absolute humidity of the processing air, and the re-heating coil 13 reheats, so that the relative humidity of the processing air can be lowered. it can. That is, an operation with a large dehumidification amount, in other words, a small sensible heat ratio can be performed. Here, the sensible heat ratio is a ratio of the sensible heat to the total amount of heat in the air conditioning load. That is, it can be calculated by the formula (sensible heat) / (sensible heat + latent heat). This is the sensible heat ratio of the air conditioner obtained by subtracting the sensible heat of the process air at the outlet from the sensible heat of the air processed at the inlet of the air conditioner, and dividing the difference by the total heat difference as the sensible heat ratio of the air conditioner. It is said that it is operated at that sensible heat ratio.
[0034]
Cold water from a chiller 31 serving as a heat source device is supplied to the main coil 12 through a cold water supply pipe 32. The processing air is cooled by the main coil 12, and the cold water whose temperature has risen returns to the chiller 31 through the cold water return pipe 33. The main coil 12 is not limited to a cooler using cold water, and may be a so-called direct expansion type. That is, the refrigerant gas compressed by the compressor is condensed by the condenser, the condensed refrigerant liquid is supplied to the main coil 12 through the expansion valve, and the processing air is cooled by evaporation of the refrigerant liquid, and the refrigerant gas evaporated there May be returned to the compressor.
[0035]
When operating in the dehumidification mode, the height of the liquid surface of the refrigerant liquid accumulated below in each of the pre-cooling coil 11 and the reheating coil 13 depends on the flow resistance of the first refrigerant path 21 and the second refrigerant path. Is substantially the same level if neglect. Actually, the height on the pre-cooling coil 11 side becomes lower than the height on the reheating coil side by the flow resistance of the refrigerant liquid flowing through the first refrigerant path 21. Also, the flow resistance of the refrigerant gas flowing through the second refrigerant path has some influence on the refrigerant liquid level.
[0036]
The solenoid valve is controlled by a controller 17 which has received signals of the humidity and temperature of the processing air before flowing into the pre-cooling coil 11 detected by the humidity sensor 15 and the temperature sensor 16.
[0037]
When the humidity of the processing air is equal to or higher than the set humidity and the temperature is equal to or lower than the set temperature plus a predetermined temperature difference (0 to 2 ° C.), the controller 17 opens the solenoid valve 14 and switches the operation of the air conditioner 10 to the dehumidification mode.
[0038]
Next, a case where the air conditioner 10 of the present embodiment is operated in the cooling mode will be described with reference to the flowchart of FIG.
[0039]
In the cooling mode, the solenoid valve 14 is closed by a command from the controller 17. In the figure, a black valve indicates that the valve is closed. Since the electromagnetic valve 14 is closed, the refrigerant liquid does not flow through the first refrigerant path 21.
[0040]
At this time, the refrigerant liquid in the precooling coil 11 is heated and evaporated by the processing air flowing on the fin side of the precooling coil 11. The evaporated refrigerant gas flows from the precooling coil 11 to the reheating coil 13 through the second refrigerant path 22. The refrigerant gas flowing into the reheating coil 13 is cooled and condensed by the processing air flowing on the fin side of the reheating coil 13. The condensed refrigerant liquid accumulates in the reheat coil 13. Since the solenoid valve 14 is closed, the refrigerant liquid stored in the reheating coil 13 does not move to the precooling coil 11.
[0041]
After a while, the refrigerant liquid in the pre-cooling coil 11 disappears, and it becomes a dry state. At this time, the flow of the refrigerant from the pre-cooling coil 11 to the reheating coil 13 is stopped in a state where the refrigerant is at the saturation pressure determined by the temperature of the processing air flowing on the fin side of the reheating coil 13. In this way, most of the refrigerant is stored in the reheat coil 13 as a refrigerant liquid. That is, the refrigerant liquid level in the reheat coil 13 increases as shown in the figure.
[0042]
In this state, indirect heat exchange between the processing air by the precooling coil 11 and the reheating coil 13 is not performed. Therefore, the processing air is only cooled by the main coil 12, the amount of dehumidification is reduced, and the sensible heat ratio is increased. That is, the operation is in the cooling mode.
[0043]
Next, the operation of the air conditioner 10 in the dehumidification mode will be described with reference to the psychrometric chart in the dehumidification mode shown in FIG. 5 and the configuration as appropriate with reference to FIG. In the drawing, the alphabetic symbols K, X, L, and M indicate the state of air in each part. This symbol corresponds to the alphabet circled in the flowchart of FIG.
[0044]
In the figure, processing air (state K) from an unillustrated air-conditioned space is sent to a precooling coil 11 through a processing air path, where it is cooled to a certain extent by a refrigerant that evaporates. Since this is preliminary cooling before cooling to the dew point temperature (below) by the main coil 12, it can be called precooling. During this time, while being cooled by the pre-cooling coil 11 and when the temperature in the state K is low, the point X is reached while the moisture is removed to some extent and the absolute humidity is slightly reduced. Point X is on the saturation line. Alternatively, in the pre-cooling stage, cooling may be performed to an intermediate point between the saturation line and the point X (this is the case in the figure). Alternatively, the cooling may be performed to a point where the temperature slightly exceeds the saturation line and shifts to the low humidity side on the saturation line.
[0045]
The pre-cooled processing air is introduced into the main coil 12 through the processing air path. Here, the processing air is cooled to its dew point temperature (below) by the cold water supplied from the chiller 31, which is a heat source unit, and while the moisture is deprived, the absolute humidity is reduced and the dry bulb temperature is lowered to reduce the point L. To reach. The bold line indicating the change from the point X to the point L is drawn off the saturation line for convenience, but actually overlaps the saturation line at least partially.
[0046]
The processing air in the state of the point L flows into the reheating coil 13 through the processing air path. Here, the refrigerant is heated with the absolute humidity kept constant by the refrigerant condensed in the reheating coil 13 and reaches the point M. At the point M, the absolute humidity is sufficiently lower than the point K, and the dry-bulb temperature is not too low.
[0047]
The precooling coil 11 and the reheating coil 13 precool the processing air by evaporating the refrigerant in the precooling coil 11, and reheat the processing air by condensing the refrigerant in the reheating coil 13. Then, the refrigerant evaporated in the precooling coil 11 is condensed in the reheating coil 13. In this way, the heat exchange between the processed air before and after being cooled by the main coil 12 is indirectly performed by the evaporation and condensation of the same refrigerant.
[0048]
Here, in the cycle on the air side shown on the psychrometric chart of FIG. 5, the heat amount of pre-cooling the processing air by the pre-cooling coil 11, that is, the heat amount ΔH of re-heating the processing air by the re-heating coil 13 is the heat recovery amount, The amount of heat obtained by cooling the processing air by the main coil 12 is ΔQ. The cooling effect of cooling the air-conditioned space is Δi.
The enthalpy difference Δi is the difference in the enthalpy of the treated air from entering the dehumidifying / cooling unit (consisting of the main coil 12, the pre-cooling coil 11, and the reheating coil 13) until exiting. This is constant regardless of the presence or absence of the pre-cooling coil 11 and the reheating coil 13.
[0049]
The intersection of the isenthalpy line passing through the point M and the line XL is defined as M ′. A point M ′ represents the state of the processing air flowing out of the dehumidifying and cooling unit (consisting of the main coil 12), assuming that there is no pre-cooling coil 11 and re-heating coil 13. The line connecting the point K and the point M ′ represents the sensible heat ratio SHF-0 (cooling mode). The line connecting the points K and M indicates the sensible heat ratio SHF-1 (dehumidification mode).
[0050]
For the dehumidifying and cooling unit, there is a relationship of sensible heat ratio SHF-0> sensible heat ratio SHF-1. When the sensible heat ratio is small, in other words, when the latent heat ratio is large (the slope is large on the psychrometric chart), the dehumidification amount can be increased at the same cooling enthalpy difference (Δi). That is, when the pre-cooling coil 11 and the reheating coil 13 are provided as in the present embodiment, the sensible heat ratio becomes small as shown by SHF-1 in the drawing, and the amount of dehumidification can be increased.
[0051]
Note that ΔH + ΔQ−Δi = Δh is an increase in the dehumidifying capacity due to the provision of the pre-cooling coil 11 and the reheating coil 13. Assuming that the area of the pre-cooling coil 11 and the re-heating coil 13 which are the indirect heat exchange sections is reduced in the dehumidifying and cooling section, Δh becomes small, and when the area finally becomes zero, the point M becomes It overlaps with point M '. This is the same as when the dehumidifying / cooling unit has become a normal cooling device (consisting of the main coil 12) having no special dehumidifying effect.
[0052]
In the dehumidification cooling section of the present embodiment, in the dehumidification mode, the indirect heat exchange section composed of the pre-cooling coil 11 and the reheating coil 13 is used as a reheat (reheat) heat exchanger for processing air before and after passing through the main coil 12. As a result, the amount of moisture condensed by cooling can be increased from that in the cooling mode, and the dehumidifying ability, that is, the latent heat treatment ability can be increased. Thus, in the dehumidification mode, the humidity can be rapidly reduced, and it is possible to cope with a so-called low sensible heat ratio and a high humidity air conditioning load such as during the rainy season.
[0053]
In the above embodiment, the heat source device has been described as a chiller for producing cold water, but is not limited thereto, and may be a heat storage tank for storing cold water. The heat source device for producing cold water may be an absorption refrigerator or a turbo refrigerator.
[0054]
In the above-described embodiment, the controller 17 opens and closes the solenoid valve 14 based on the detection values of both the humidity sensor 15 and the temperature sensor 16. May be opened and closed.
[0055]
In the above embodiment, the on-off valve provided in the second refrigerant path 22 is described as an electromagnetic valve, but may be an air-operated diaphragm valve, a cylinder valve, or an on / off valve. The present invention is not limited to this, and may be an on-off valve that opens and closes while adjusting the opening from step to step in a stepless manner. At this time, the ratio of pre-cooling / reheating to cooling by the main coil 12 can be adjusted steplessly.
[0056]
Further, according to the air conditioner of the present embodiment, excessive dehumidification can be prevented, so that drying of the skin can be prevented, and activation of harmful virus activity can also be prevented. In this way, it is possible to solve the problem of generating indoor air quality (IAQ: Indoor Air Quality) that is not desirable for health. It is also energy efficient and has excellent driving economy.
[0057]
Since the solenoid valve 14 is provided in the first refrigerant path 21, the valve needs to be a small-diameter valve, and is excellent in economy and compactness.
Also, since the air conditioning load is directly reflected on the heat source unit, the load response and reliability are excellent.
It is possible to maintain the indoor humidity at an appropriate level without performing energy-consuming reheating and dehumidification, which has been widely used in humid areas. A safe environment can be provided.
[0058]
The air conditioner according to the embodiment of the present invention is suitable as an air conditioner for a central type air conditioner.
[0059]
【The invention's effect】
As described above, according to the present invention, since the opening / closing valve for adjusting the flow rate of the refrigerant is provided in the first refrigerant path or the second refrigerant path, the flow rate of the refrigerant flowing between the precooler and the reheater is provided. Therefore, it is possible to provide an air conditioner having a variable sensible heat ratio, and to provide an energy-saving air conditioning system that does not perform useless cooling or dehumidification.
[Brief description of the drawings]
FIG. 1 is a flowchart of an air conditioner according to an embodiment of the present invention.
FIG. 2 is a schematic perspective view showing an example of a pre-cooling coil and a reheating coil suitable for the embodiment of the present invention.
FIG. 3 is a flowchart when the air conditioner shown in FIG. 1 is operated in a dehumidification mode.
FIG. 4 is a flowchart when the air conditioner shown in FIG. 1 is operated in a cooling mode.
FIG. 5 is a psychrometric chart illustrating the operation of the air conditioner according to the embodiment of the present invention in the dehumidification mode.
FIG. 6 is a flowchart of a conventional air conditioner.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Air conditioner 11 Pre-cooling coil 12 Main coil 13 Reheating coil 14 Solenoid valve 15 Humidity sensor 16 Temperature sensor 17 Controller 18 Fan 21 First refrigerant path 22 Second refrigerant path 31 Chiller 32 Cold water supply pipe 33 Cold water return pipe

Claims (3)

An air cooler for cooling the processing air;
A pre-cooler for pre-cooling the processing air by evaporating a refrigerant before cooling the air with the air cooler;
A reheater that heats the condensed refrigerant after cooling the process air with the air cooler;
A first refrigerant path for sending the condensed refrigerant from the reheater to the precooler;
A second refrigerant path for sending the evaporated refrigerant from the precooler to the reheater;
An on-off valve for adjusting the flow rate of the refrigerant is provided in the first refrigerant path or the second refrigerant path;
air conditioner. The first refrigerant path is provided vertically downward relative to the precooler and the reheater, and the second refrigerant path is positioned relative to the precooler and the reheater. The air conditioner according to claim 1, wherein the air conditioner is provided vertically upward, and the on-off valve is provided in the first refrigerant path. 2. A humidity detector that detects the humidity of the processing air, and a controller that receives a detection signal of the humidity detector and controls opening and closing of the on-off valve according to the humidity of the processing air. Or the air conditioner according to claim 2.

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