JP4886611B2 - Air conditioning controller - Google Patents

Description

  The present invention relates to an air conditioning control device that reduces wasteful energy consumption.

  Factors that affect the thermal sensation of the human body include room temperature, room humidity, average radiation temperature, activity, clothing, and air velocity. However, since the air velocity in a place where a person is present in an office building is usually 0.1 m / s or less, there is almost no influence on the thermal feeling. The amount of clothes is fixed in the summer and winter seasons, and the amount of activity is determined by the purpose of the building, such as office buildings and department stores. Further, the average radiation temperature substantially follows room temperature except for the window side.

  Therefore, considering each influencing factor, humidity greatly affects human comfort, except for room temperature.

  However, most of the air conditioning control in many office buildings is only room temperature control, and the actual situation is that no consideration is given to humidity. This is because, when trying to control humidity during cooling, a general air conditioner is arranged in the order of a cooling coil and a heating coil, and the cooling coil performs dehumidification by supercooling, so the heating coil is used to adjust the room temperature. This is because an air reheating cycle process is required at, and as a result, a very large amount of energy is consumed as compared with the case of temperature control alone.

  Therefore, recently, in order to solve the above-described problems, a direct expansion coil is added to the air conditioner in addition to the cold / hot water coil to suppress the consumption of extra energy generated during reheating for room temperature adjustment in temperature and humidity control. Air conditioning control devices have been proposed.

As shown in FIG. 6, this air conditioner mixes a direct expansion coil 51 that introduces external air and cools or heats it with a refrigerant, and external air cooled or heated by the direct expansion coil 51 and return air from the room. Then, a mixing mechanism including a damper 52, pipes 53, 54, and the like for generating mixed air, and the generated mixed air is cooled or heated with cold water or hot water to adjust the supply air temperature into the room. A cold / hot water coil 55 is provided. 56 is a condenser, 57 is a compressor, 58 is a damper, 59 is a valve, and 60 is an air supply fan (Patent Document 1).
JP 2006-292300 A (see FIG. 1)

  By the way, the air conditioning control device for an air conditioner shown in the above-mentioned patent document performs temperature control by changing the flow rate of cold water or hot water introduced into the cold / hot water coil 55, and also controls the flow rate of refrigerant introduced into the direct expansion coil 51. Since variable humidity control is performed, energy control is independently performed for temperature control and humidity control.

  However, in the air conditioning control device for an air conditioner described in the patent document, the temperature control system and the humidity control system are not completely independent, and the temperature control system and the humidity control system have a relationship of mutual interference as described below. . For example, as shown in FIG. 7, when the room temperature / humidity is well controlled based on the room temperature set value of 26.0 ° C and the humidity set value of 50.0 (%), the room temperature is set by the disturbance. When the humidity drops slightly, the absolute humidity does not change, but the saturated water vapor amount decreases, so the relative humidity is set based on the formula of relative humidity (%) = absolute humidity (g) / saturated water vapor amount (g). Higher than the value.

  FIG. 8 is also a diagram for explaining the interference between the temperature control system and the humidity control system. The room temperature falls by −0.5 ° C. with respect to the room temperature set value of 26.0 ° C. and the humidity set value of 40.0 (%). In this case, the relative humidity is increased by 1.2 (%).

  Accordingly, as described above, when the room temperature falls below the room temperature setting value due to disturbance as described above, the relative humidity becomes higher than the humidity setting value, so that the humidity is reduced, that is, the refrigerant to the direct expansion coil 51 is used. Air flow is dehumidified (supercooled) by controlling the flow rate. As a result, the supply air temperature decreases, and the indoor temperature further decreases accordingly. Conversely, when the room temperature rises due to disturbance, the relative humidity decreases as shown in FIGS.

  Therefore, conventionally, as a technique for preventing interference between control systems, means for canceling the interference characteristic by interposing a non-interference element between the controller and the process having the interference characteristic has been taken. Such a control system is called a non-interacting control system.

  FIG. 9 is a configuration diagram of a non-interference control system to which a compensation element is added in order to remove mutual interference between the temperature control system and the humidity control system.

  That is, the non-interference control system includes a compensation element between the room temperature / indoor humidity controllers 61 and 62 and the room temperature process 64 including the process 63 having interference characteristics and the humidity process 66 including the process 65 having interference characteristics. The interference compensation element 67 is inserted, and the interference characteristics of the processes 63 and 65 are changed by the non-interference compensation element 67 on the output side of the room temperature / indoor humidity controller 61 and 62 with respect to the input temperature setting value and humidity setting value. It acts to counteract.

  The room temperature process 64 corresponds to a cold / hot water coil or the like. The humidity process 66 corresponds to a direct expansion coil or the like.

  FIG. 10 is a diagram equivalently representing the non-interference control system shown in FIG. 9 by a process transfer function. In the figure, Gc12 (s) and Gc21 (s) are decoupling compensation elements, and G11 (s), G21 (s), G12 (s) and G22 (s) are represented by process transfer functions.

In this non-interference control system, in order to cancel the influence of mutual interference caused by the process transfer functions G11 (s), G21 (s), G12 (s), G22 (s), the non-interference compensation element Gc12 (s), For Gc21 (s), the following condition is essential.
Gc12 (s) = G12 (s) / G22 (s)
Gc21 (s) = G21 (s) / G11 (s)
However, as is apparent from the above equation, in order to determine the compensation elements Gc12 (s) and Gc21 (s), the process transfer functions G11 (s), G21 (s) and G12 (s ), G22 (s) must be accurately identified. For this purpose, it is necessary to identify the process transfer function by applying a test signal over a long period of time and analyzing the input / output waveform of the process, but it is very difficult to accurately identify the process transfer function.

  The present invention has been made in view of the above circumstances, and by eliminating mutual interference between the temperature control system and the humidity control system, unnecessary energy consumption due to mutual interference is eliminated, and reliable independent control of temperature and humidity is realized. An object of the present invention is to provide an air conditioning control device.

In order to solve the above problems, the present invention provides a temperature control system that controls the room temperature by controlling the flow rate of cold water or hot water introduced into the cold / hot water coil so that the room temperature becomes a temperature set value, and the room humidity is An air conditioning control device having a humidity control system that controls indoor humidity by controlling the flow rate of a refrigerant introduced into a direct expansion coil so that a humidity setting value is obtained, and a calculation program for obtaining a state value of humid air used, the temperature set value, and humidity tolerance value determining means for determining the allowable value β for the humidity set value from the allowable value α for the humidity set point and the temperature set value, tolerance α and the humidity on the temperature set value When the allowable value β for the set value is set, the room temperature is within the room temperature set value ± α, and the indoor humidity is within the humidity set value ± β, a humidity control stop command is sent to the humidity control system. Size When the room temperature deviates from the room temperature set value ± α or when the room humidity deviates from the humidity set value ± β, a humidity control stop release command is sent to the humidity control system to control the humidity. And a humidity control stop canceling means for restarting.

  According to the present invention, by eliminating the mutual interference between the temperature control system and the humidity control system, it is possible to eliminate the consumption of extra energy due to the mutual interference, and to realize complete independent control of temperature and humidity. .

  Prior to describing an embodiment of an air conditioning control device according to the present invention, an example of an air conditioner to which the air conditioning control device is applied will be described with reference to FIG.

  This air conditioner has a direct expansion coil 2 that cools or heats external air introduced from the outside by a refrigerant whose flow rate is adjusted by an expansion valve 1, and return air that passes from a room (air conditioning zone) 3 through a damper 4. A chilled / hot water coil 6 for controlling a supply air temperature to the room 3 by cooling or heating a part of the chilled / hot water flow rate adjusting valve 5 with a chilled water or a hot water from a central heat source whose flow rate is adjusted. Air whose temperature and humidity are controlled by the expansion coil 2 and the cold / hot water coil 6 is supplied to the room 3 by the supply fan 7.

The direct expansion coil 2 is connected in series with a compressor 8 that compresses the refrigerant, a condenser 9 that condenses the condensed refrigerant, and an expansion valve 1 that adjusts the flow rate so as to expand the condensed refrigerant.
It is configured as a so-called refrigerant cycle.

  In the refrigerant cycle, the refrigerant introduced from the direct expansion coil 2 is compressed by the compressor 8 to become a high-temperature and high-pressure gas state, and is introduced into the condenser 9. In the condenser 9, the refrigerant gas in a high temperature and high pressure state is cooled by the return cold water from the cold / hot water coil 6 and introduced into the direct expansion coil 2. An expansion valve 1 is provided between the condenser 9 and the direct expansion coil 2, and the cooled refrigerant is led to the direct expansion coil 2 in an expanded state while adjusting the flow rate. As a result, the refrigerant gas introduced in the direct expansion coil 2 is rapidly lowered to a low pressure and a low temperature, and the outside air introduced from the outside is cooled. Reference numeral 10 denotes a damper.

  A temperature sensor 11 and a humidity sensor 12 are installed in the room 3, and the room temperature and humidity measured by the sensors 11 and 12 are used for room temperature control and room humidity control described later.

  Hereinafter, an embodiment of an air-conditioning control apparatus according to the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 2 is a block diagram showing Embodiment 1 of the air conditioning control device according to the present invention.
The air conditioning control device 20 according to the present invention includes a temperature setting unit 21 and a humidity setting unit 22 that store a preset room temperature setting value and a humidity setting value, a room temperature control block unit 23, and an indoor humidity control block unit 24, The room 3 includes a room temperature determination unit 25 and a humidity determination unit 26 that determine a room temperature state and a humidity state, and a humidity control stop cancellation unit 27.

  For example, the temperature setting unit 21 and the humidity setting unit 22 may be configured to divide into regions and set a room temperature setting value and a room humidity setting value in one data setting unit.

  The room temperature control block 23 is based on a deviation value between the room temperature set value stored in the temperature setting unit 21 and the room temperature measured by the temperature sensor 11, PI (P: proportional, I: integral) or PID (D: derivative). ) The flow rate of cold water or hot water introduced into the cold / hot water coil 6 constituting the room temperature process 28 from the central heat source via the flow rate adjustment valve 5 using a control algorithm for performing calculations and the like so that the room temperature becomes a room temperature set value. Have the ability to control. Here, the room temperature process 28 is a generic term for a process including the cold / hot water coil 6 for controlling the room temperature and the components related to the temperature control, for example, the flow rate adjusting valve 5.

  The indoor humidity control block unit 24 is based on a deviation value between the humidity set value stored in the humidity setting unit 22 and the room humidity measured by the humidity sensor 12, PI (P: proportional, I: integral) or PID (D : Control of the flow rate of the refrigerant introduced into the direct expansion coil 2 constituting the indoor humidity process 29 through the expansion valve 1 using a control algorithm for performing a calculation or the like so that the indoor humidity becomes a humidity set value. Have the ability to Here, the indoor humidity process 29 is a process that collectively refers to the components of the refrigerant cycle including the direct expansion coil 2 that controls the indoor humidity.

  The room temperature determination unit 25 sets ± α (allowable value) in advance, compares the room temperature measured by the temperature sensor 11 with the room temperature setting value ± α stored in the temperature setting unit 21, and measures the temperature sensor 11. When the room temperature is within the room temperature set value ± α, the humidity determination unit 26 is notified of determination data for determining that the room temperature is good. Further, when the room temperature deviates from the room temperature set value ± α, it has a function of notifying the humidity control stop canceling unit 27 of determination data for determining a room temperature failure state.

  The humidity determination unit 26 sets ± β (allowable value) in advance, compares the indoor humidity measured by the humidity sensor 12 with the humidity set value ± β, and the indoor humidity measured by the humidity sensor 12 is the humidity set value. When it is within ± β and the determination data indicating that the room temperature is good is received from the room temperature determination unit 25, a humidity control stop command is sent to the indoor humidity control block unit 24.

  When the indoor humidity control block unit 24 receives a humidity control stop command from the humidity determination unit 26, the indoor humidity control block unit 24 stops humidity control.

  When the room temperature / room humidity is in a good state, the humidity control stop canceling unit 27 stops the humidity control according to the humidity control stop command described above, but from the room temperature determining unit 25 or the humidity determining unit 26. When receiving determination data indicating that the room temperature and the room humidity are not in a good state, a humidity control stop release command is sent to the room humidity control block unit 24.

  Next, the operation of the air conditioning control device configured as described above will be described.

  The room temperature control block unit 23 captures the room temperature measured by the temperature sensor 11 every predetermined period, and based on the deviation value between the captured room temperature and the room temperature setting value stored in the temperature setting unit 21, PI or PID calculation, etc. To obtain an operation signal such that the room temperature approaches the room temperature set value. And the flow control valve 5 is operated using this acquired operation signal, the flow volume of the cold water or warm water introduced into the cold / hot water coil 6 from a central heat source is adjusted, and it controls so that room temperature will be in an optimal state. .

  On the other hand, the indoor humidity control block unit 24 executes the original humidity control accompanying the stop of the humidity control or the release of the stop of the humidity control selectively and appropriately according to the determination results of the room temperature determination unit 25 and the humidity determination unit 26.

That is, the room temperature determination unit 25 takes in the room temperature measured by the temperature sensor 11 for each predetermined period,
When there is a relationship of room temperature set value−α ≦ room temperature ≦ room temperature set value + α, (1)
It is determined that the room temperature in the room 3 is in a good state, and determination data for setting the room temperature in a good state is sent to the humidity determination unit 26.

Here, the humidity determination unit 26 receives the determination data for determining that the room temperature is good from the room temperature determination unit 25 and takes in the indoor humidity measured by the humidity sensor 12.
If there is a relationship of humidity setting value -β ≤ humidity ≤ humidity setting value + β, (2)
It is determined that the temperature and humidity of the room 3 are good, and a humidity control stop command is sent from the humidity determination unit 26 to the indoor humidity control block unit 24.

  Upon receiving the humidity control stop command, the indoor humidity control block unit 24 sets, for example, a flag “0” and stops control of the indoor humidity.

  However, when the room temperature is not in the relationship of room temperature set value−α ≦ room temperature ≦ room temperature set value + α in the room temperature determination unit 25, or in the humidity determination unit 26, the room humidity is humidity set value−β ≦ humidity ≦ humidity setting. When there is no relationship of the value + β, it is determined that the room temperature and the room humidity of the room 3 are not in a good state, and the humidity control stop release unit 27 sends a humidity control stop release command to the room humidity control block unit 24.

  Upon receiving the humidity control stop cancellation command, the indoor humidity control block unit 24 clears, for example, the flag “0”, sets the flag “1”, cancels the humidity control stop, and executes humidity control.

  That is, when the humidity control stop cancellation command is received from the humidity control stop cancellation unit 27, the indoor humidity control block unit 24 captures the indoor humidity measured by the humidity sensor 12 at predetermined intervals, and the captured indoor humidity and humidity. Based on the deviation value from the humidity setting value stored in the setting unit 22, PI or PID calculation or the like is executed to obtain an operation signal that causes the room humidity to approach the humidity temperature setting value. Then, the expansion valve 1 is operated using the acquired operation signal, the flow rate of the refrigerant introduced into the direct expansion coil 2 is adjusted, and the indoor humidity is controlled.

  Therefore, according to the embodiment as described above, based on the comparison result between the measured value and the set value ± allowable values α and β, when the room temperature and the indoor humidity are both in a good state, only the indoor humidity control is performed. This eliminates the need to identify the process transfer function, eliminates mutual interference between the temperature control system and the humidity control system, and maintains good temperature and humidity without consuming excess energy. .

  Further, when either one of the room temperature and the room humidity is not in a good state, the control of the room humidity is resumed and the operation of the refrigerant introduced into the direct expansion coil 2 is started, so that the room temperature and the room humidity are shifted to a good state. be able to.

  In the above-described embodiment, the room temperature determination unit 25 and the humidity determination unit 26 determine whether the room temperature and the room humidity are good or bad according to the above formulas (1) and (2), and are particularly determined to be bad. When it does, output a humidity control stop release command.

  However, when releasing the humidity control stop, a hunting phenomenon may occur.

  Therefore, it is possible to take a hunting prevention measure for the temperature setting value ± α and the humidity setting value ± β that are the determination threshold values. Specifically, the humidity control stop release command may be output only when the room temperature is not within the room temperature set value ± (α + Δα) or when the humidity is not within the humidity set value ± (β + Δβ).

(Embodiment 2)
FIG. 3 is a block diagram showing Embodiment 2 of the air conditioning control device according to the present invention. Since this air conditioning control device is substantially the same as that of the first embodiment, the same or equivalent parts are denoted by the same reference numerals as those in FIG. 2, and the detailed description thereof will be given in the description of FIG.

  In this air-conditioning control device, the difference is that the temperature set value, the humidity set value, and the allowable value α can be obtained without providing a predetermined fixed allowable value β by newly providing a humidity allowable value β determining unit 30. Accordingly, the β value is arbitrarily determined and set in the humidity determination unit 26.

  The allowable humidity value β determination unit 30 stores a humid air state value calculation program used in creating an air diagram in the CPU. Incidentally, as an example of an air diagram, FIG. 4 shows a wet air h-x diagram, which is one of the most basic data on air conditioning equipment. Based on the room temperature setting value, the humidity setting value, and the above-described allowable value α, the allowable value β related to the indoor humidity is determined using the wet air state value calculation program.

  Incidentally, if the allowable value α of the room temperature set value α = 0.5 ° C., the room temperature set value = 26 ° C., and the humidity set value (relative humidity) = 50%, the state value β becomes β = 1.5 from FIG. .

  Further, the state value β becomes β = 1.2 from FIG. 8 when the room temperature set value allowable value α = 0.5 ° C., the room temperature set value = 26 ° C., and the humidity set value (relative humidity) = 40%. .

  7 and 8 are obtained by using the wet air state value calculation program used for obtaining the air state value described above. That is, in the middle row of each figure, the absolute humidity was calculated from the room temperature setting value and the humidity setting value (relative humidity) using the humid air state value calculation program. The upper and lower lines of each figure are calculated by calculating the relative humidity from the absolute humidity (the absolute humidity of the room 3 does not change in a short time) and the room temperature set value ± α using the humid air condition value calculation program. This is an example.

  Therefore, according to the above-described embodiment, the humidity allowable value β determination unit 30 is newly provided in the configuration of the first embodiment, and the wetness based on the original physical calculation formula used when drawing the air diagram. Using the air condition value calculation program, the room temperature set value, the humidity set value, and the allowable value α are taken in and the allowable value β is determined at any time and set in the humidity determination unit 26. Therefore, the room temperature set value, the humidity set value, and the allowable value α Accordingly, it is possible to accurately determine whether or not the room 3 is in a good state using the optimum allowable value β.

(Embodiment 3)
FIG. 5 is a block diagram showing Embodiment 3 of the air conditioning control device according to the present invention. Since this air conditioning control device is substantially the same as that of the first embodiment, the same or equivalent parts are denoted by the same reference numerals as those in FIG. 2, and the detailed description thereof will be given in the description of FIG.

  In this air conditioning control device, the difference is that a set value change presence / absence determining unit 31 is newly provided. The air conditioning control device sends a humidity control stop release command to the indoor humidity control block unit 24 according to the determination data that the room temperature determination unit 25 and the humidity determination unit 26 always indicate that the room temperature and the room humidity are not good. In this configuration, the control is resumed.

  However, in this embodiment, the set value change presence / absence determining unit 31 takes in the room temperature set value, and when the room temperature set value changes, the room is forcibly set in the room for N1 hours (for example, 10 minutes). A humidity control command is sent to the humidity control block unit 24. The indoor humidity control block unit 24 performs humidity control based on the humidity control command.

  At this time, when the humidity control command is received, the indoor humidity control block unit 24 continues the humidity control for a predetermined time N1 from the time of change, and has already stopped the indoor humidity control if the humidity control is already in progress. If so, the indoor humidity control is restarted and the humidity control is executed for a predetermined time N1 from the time of change.

  The set value change presence / absence determination unit 31 determines whether or not the room temperature set value has changed, and sends a humidity control command when there is a change in the room temperature set value. However, for example, the humidity set value is captured and the humidity set value changes. In this case, the configuration may be such that the humidity control command is forcibly sent to the indoor humidity control block unit 24 for N2 hours (for example, N1> N2) from this change time point to execute the humidity control.

  According to this embodiment, when the room temperature set value or the humidity set value changes, the humidity control is executed until the state of the room 3 settles, thereby quickly shifting to the optimum room state when the set value changes. Can be made.

  In addition, although this Embodiment demonstrated the example applied to Embodiment 1, it cannot be overemphasized that it can apply similarly to Embodiment 2. FIG.

  In addition, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention.

  For example, a temperature setting value and a humidity setting value are determined using a comfort index (PMV, standard effective temperature, etc.) of human thermal sensation, which is a well-known technique, and each room satisfying these temperature setting value and humidity setting value is determined. Means for obtaining a set of room temperature and room humidity, and means for selecting a temperature and humidity value for energy saving in consideration of the outside air temperature and the air conditioning load at regular intervals from these sets. The humidity value may be used as the temperature setting value and the humidity setting value.

  Further, the embodiments can be implemented in combination as much as possible, and in that case, an effect can be obtained by the combination.

The block diagram which shows an example of the air conditioning machine to which the air-conditioning control apparatus which concerns on this invention is applied. The block diagram explaining Embodiment 1 of the air-conditioning control apparatus which concerns on this invention. The block diagram explaining Embodiment 2 of the air-conditioning control apparatus which concerns on this invention. The damp air hx diagram used as basic data about air conditioning equipment. The block diagram explaining Embodiment 3 of the air-conditioning control apparatus which concerns on this invention. The block diagram which shows an example of the conventional air conditioner. The calculation result figure which calculated | required absolute humidity etc. from room temperature setting value and humidity setting value (relative humidity) using the humid air state value calculation program. Another calculation result figure which calculated | required absolute humidity etc. from room temperature setting value and humidity setting value (relative humidity) using the humid air state value calculation program. The block diagram of the non-interference control system which added the compensation element in order to remove the mutual interference between a temperature control system and a humidity control system. FIG. 10 is a diagram equivalently representing the non-interference control system shown in FIG. 9 by a process transfer function.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Expansion valve, 2 ... Direct expansion coil, 3 ... Indoor (air-conditioning zone), 5 ... Cold / hot water flow control valve, 6 ... Cold / hot water coil, 7 ... Supply air fan, 11 ... Temperature sensor, 12 ... Humidity sensor, 20 Air conditioning controller, 21 Temperature setting unit, 22 Humidity setting unit, 23 Room temperature control block unit, 24 Indoor humidity control block unit, 25 Room temperature determination unit, 26 Humidity determination unit, 27 Humidity control stop release Part, 28 ... room temperature process, 29 ... indoor humidity process, 30 ... humidity allowable value β determination part, 31 ... set value change presence / absence judgment part.

Claims (4)

A temperature control system that controls the room temperature by controlling the flow rate of cold water or hot water introduced into the cold / hot water coil so that the room temperature becomes the temperature set value, and the direct expansion coil so that the room humidity becomes the humidity set value In the air conditioning control device having a humidity control system for controlling the indoor humidity by controlling the flow rate of the refrigerant ,
Using a calculation program for calculating a humid air state value, a humidity allowable value determining means for determining an allowable value β for the humidity set value from the temperature set value, the humidity set value and the allowable value α for the temperature set value;
When the allowable value α for the temperature set value and the allowable value β for the humidity set value are set, the room temperature is within the room temperature set value ± α, and the room humidity is within the humidity set value ± β, the humidity control Determination means for sending a humidity control stop command to the system;
When the room temperature deviates from the room temperature set value ± α, or when the room humidity deviates from the humidity set value ± β, a humidity is sent to the humidity control system to release a humidity control stop and restart the humidity control. An air conditioning control device comprising a control stop canceling means. In the air-conditioning control device according to claim 1,
In order to prevent a hunting phenomenon when releasing the humidity control stop, the determination means is used when the room temperature deviates from the room temperature set value ± (α + Δα) or the room humidity deviates from the humidity set value ± (β + Δβ). Then, an air conditioning control device that sends a humidity control stop release command to the humidity control system via the humidity control stop release means. In the air conditioning control device according to claim 1 or 2,
A setting value change presence / absence judging means for judging whether or not the temperature set value has changed is provided;
When the set value change presence / absence determining means determines that there is a change in the temperature set value, a humidity control command is sent to the humidity control system for a predetermined time N1 from the time of change to forcibly execute the humidity control. An air conditioning control device. In the air-conditioning control device according to any one of claims 1 to 3,
A setting value change presence / absence judging means for judging whether or not the humidity set value has changed,
When the set value change presence / absence determining means determines that there is a change in the humidity set value , a humidity control command is sent to the humidity control system for a predetermined time N2 from the time of change to forcibly execute the humidity control. An air conditioning control device.

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