JP3233615B2 - Air conditioner dehumidification control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to control of an air conditioner, and more particularly to control of a dehumidifying operation in an air conditioner capable of performing cooling, dehumidifying and heating operations.

[0002]

2. Description of the Related Art Conventionally, in a dehumidifying operation of an air conditioner, dehumidified air is blown into a room through a wind direction changing blade set downward in an indoor unit. However, if the wind direction changing blades are set downward, the cold air directly hits the indoor occupants, causing a problem of causing chills or discomfort, so that the cold air does not hit the indoor occupants,
There has also been proposed one in which the wind direction changing blade is set in the horizontal direction (for example, see Japanese Patent Application Laid-Open No. 10-61999).

Recently, there has been proposed an air conditioner adopting a so-called short circuit system in which cold air blown from an outlet of an indoor unit flows directly into an inlet by setting a wind direction changing blade upward. By preventing the air from directly hitting the occupants of the room, comfortable dehumidification without a feeling of cool air is achieved (see, for example, JP-A-9-72599).

[0004]

However, when the dehumidifying operation is performed, the room temperature gradually decreases. In some cases, the skin feels cold even though the dehumidification is insufficient. Therefore, the dehumidification is performed without further lowering the room temperature. There is also a request to do,
There is still room for improvement in dehumidification control.

The present invention has been made in view of the above-mentioned problems of the prior art, and has improved comfort in which a resident can exhibit a sufficient dehumidifying ability without feeling chills. An object of the present invention is to provide a method for controlling dehumidification of an air conditioner.

[0006]

Means for Solving the Problems In order to achieve the above object, the invention according to claim 1 of the present invention provides an air conditioner capable of cooling, dehumidifying and heating operations, wherein a dehumidifying operation mode is selected. If the suction temperature of the indoor unit and the indoor set temperature are compared, and according to the difference between the suction temperature and the indoor set temperature, one of the cooling operation, the dehumidifying operation, and the heating operation are selected. Between the dehumidifying operation area and the heating operation area in the dehumidifying operation mode.
A heating operation is performed after a predetermined time has elapsed after the FF region is provided and the compressor is shifted from the dehumidifying operation region to the compressor OFF region.

According to a second aspect of the present invention, in the air conditioner capable of cooling, dehumidifying and heating operations, when the dehumidifying operation mode is selected, the suction temperature of the indoor unit is compared with the indoor set temperature. Depending on the difference between the suction temperature and the indoor set temperature, one of the cooling operation, dehumidification operation and heating operation is selected, and between the dehumidification operation region and the heating operation region in the dehumidification operation mode. Compressor O
After the FF area is provided, and the compressor is shifted from the dehumidifying operation area to the compressor OFF area, the compressor O
The heating operation is performed when the ratio of the total time of the FF state to the predetermined time is equal to or more than a predetermined value.

According to a third aspect of the present invention, in the air conditioner capable of cooling, dehumidifying and heating operations, when the dehumidifying operation mode is selected, the suction temperature of the indoor unit is compared with the indoor set temperature. Depending on the difference between the suction temperature and the indoor set temperature, one of the cooling operation, dehumidification operation and heating operation is selected, and between the dehumidification operation region and the heating operation region in the dehumidification operation mode. Compressor O
An FF region is provided, and after shifting from the dehumidifying operation region to the compressor OFF region, the indoor blower is stopped for a predetermined time, and the indoor blower is operated, and then the heating operation is performed.

According to a fourth aspect of the present invention, in the air conditioner capable of cooling, dehumidifying and heating operations, when the dehumidifying operation mode is selected, the suction temperature of the indoor unit is compared with the indoor set temperature. Depending on the difference between the suction temperature and the indoor set temperature, one of the cooling operation, dehumidification operation and heating operation is selected, and between the dehumidification operation region and the heating operation region in the dehumidification operation mode. Compressor O
An FF area is provided, and after shifting from the dehumidifying operation area to the compressor OFF area, the indoor blower is stopped for a predetermined time, and the activation of the compressor is delayed at the start of the heating operation.

According to a fifth aspect of the present invention, in the air conditioner capable of cooling, dehumidifying and heating operations, when the dehumidifying operation mode is selected, the suction temperature of the indoor unit is compared with the indoor set temperature. Depending on the difference between the suction temperature and the indoor set temperature, one of the cooling operation, dehumidification operation and heating operation is selected, and between the dehumidification operation region and the heating operation region in the dehumidification operation mode. Compressor O
After providing the FF region, and after shifting from the dehumidifying operation region to the compressor OFF region, stop the indoor blower for a predetermined time, and further repeat the operation and stop of the indoor blower,
A heating operation is performed.

[0011]

[0012]

[0013]

[0014]

[0015]

[0016]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an example of a refrigeration cycle diagram of an air conditioner employing dehumidification operation control according to the present invention. An outdoor unit 2 has an inverter-driven variable capacity (frequency) variable compressor 6 (hereinafter simply referred to as a compressor). ), An outdoor heat exchanger 8, and a four-way valve 10 for switching between air conditioning and heating.
On the other hand, the indoor unit 4 is provided with the indoor heat exchanger 12. The outdoor unit 2 and the indoor unit 4 are connected by a liquid-side pipe 14 and a gas-side pipe 16, and the liquid-side pipe 14 has an electric expansion that can pulse-control the valve opening degree by, for example, a stepping motor. A valve 18 is mounted.

The indoor unit 4 includes an indoor temperature sensor 22 for detecting the room temperature of the room in which the indoor unit 4 is installed, an operation mode (cooling or heating) desired by the occupant, and the room temperature and operation or stop. Operation setting circuit 24 that can set
Is provided. In the figure, 21, 23, 25 and 26 are:
A humidity sensor, an indoor pipe temperature sensor, an outside air temperature sensor, and an auxiliary throttle are shown, respectively.

In the refrigeration cycle having the above structure, during cooling, the refrigerant discharged from the compressor 6 flows from the four-way valve 10 to the outdoor heat exchanger 8, where it exchanges heat with outdoor air to condense and liquefy. Next, the refrigerant is reduced in pressure by passing through the auxiliary throttle 26, and the refrigerant is in a state of being easily evaporated.
Through the electric expansion valve 18. Since the valve opening of the electric expansion valve 18 is controlled by a predetermined control method so as to have an opening corresponding to the required load of the room, the refrigerant also has a low pressure at a flow rate corresponding to the load, and the indoor heat exchanger 12 After passing through and evaporating, the gas passes through the gas side pipe 16 and the four-way valve 10 and is sucked into the compressor 6 again through the accumulator 20. Further, the compressor frequency is determined by a predetermined control method according to the load level.

On the other hand, when the heating operation is started, the high-temperature and high-pressure refrigerant discharged from the compressor 6 passes through the four-way valve 10 and flows to the indoor heat exchanger 12 via the gas side pipe 16 to be condensed and liquefied. Then, the pressure is reduced by the electric expansion valve 18 on the liquid side pipe 14 to an intermediate pressure. The opening degree of the electric expansion valve 18 is controlled by a predetermined control method so that the opening degree matches the load of the room to be heated in the same manner as during cooling, so that the refrigerant also generates indoor heat at a flow rate corresponding to the load. It flows through the exchanger 12. The intermediate pressure refrigerant is reduced in pressure by passing through the auxiliary throttle 26 via the liquid side pipe 14 and easily evaporated, and further flows to the outdoor heat exchanger 8, where it exchanges heat with outdoor air. The refrigerant evaporated and gasified is sucked into the compressor 6 again through the accumulator 20.

Next, a method of controlling the compressor frequency and the electric expansion valve opening will be described. FIG. 2 is a block diagram showing a flow of control of the compressor frequency and the electric expansion valve opening, and FIG. 3 is a temperature zone division diagram of a temperature difference ΔT between the room temperature Tr and the set temperature Ts.

First, in the indoor unit 4, the output of the indoor temperature sensor (indoor temperature) is sent from the indoor temperature detecting circuit 28 to the temperature difference calculating circuit 30 as a temperature signal. The set temperature and operation mode that have been set are discriminated and sent to the differential temperature calculating circuit 30, where the differential temperature ΔT (= Tr−Ts) is calculated, and the frequency No. shown in FIG. Into a differential temperature signal.

The ON / OFF determination circuit 34 determines whether the indoor unit 4 is operated (ON) or stopped (OFF) set by the operation setting circuit 24. Further, the rated capacity of the indoor unit 4 is stored in the rated capacity storage circuit 36, and the rated capacity signal, the differential temperature signal, the operation mode signal, the ON-O
The FF determination signal is sent from the signal sending circuit 38 to the signal receiving circuit 40 of the outdoor unit 2. The signal received by the signal receiving circuit 40 is sent to a compressor frequency calculating circuit 42 and an expansion valve opening calculating circuit 44.

In the compressor frequency calculation circuit 42, the rated capacity signal of the indoor unit 4, the differential temperature signal, the operation mode signal, the ON-OF
The load level coefficient is read from the load coefficient table 46 shown in Table 1 below from the F discrimination signal, the load level coefficient is multiplied by a constant, and a correction value is added to determine the frequency of the compressor 6. Perform initial settings.

[Table 1]

Similarly, in the expansion valve opening calculating circuit 44, the load level is obtained from the load coefficient table 46 shown in Table 2 below based on the rated capacity signal, the differential temperature signal, the operation mode signal, and the ON / OFF discrimination signal of the indoor unit 4. The coefficient is selected, and the coefficient is read from the valve initial opening table 50 for each rated capacity shown in Table 3 below from the rated capacity of the indoor unit 4.

[Table 2]

[Table 3]

The valve opening of the electric expansion valve 18 is obtained by multiplying the load level coefficient by the initial valve opening. Expansion valve opening = P0 (load level coefficient) x initial pulse

The calculation result is sent to an expansion valve driving circuit (not shown) as an expansion valve opening signal, and at every predetermined cycle, the electric expansion valve 18 is obtained from a temperature difference signal, an operation mode signal, and an ON-OFF discrimination signal. Is calculated, the result of this calculation is corrected as necessary, and then sent to the expansion valve drive circuit as an expansion valve opening signal.

The dehumidification control method according to the present invention in the air conditioner having the above configuration will be described below with reference to the flowcharts of FIGS. When the dehumidifying operation mode is set by the operation setting circuit 24, first, in step S1, the indoor temperature Tr, the outdoor air temperature To, and the indoor piping temperature are determined by the indoor temperature sensor 22, the outdoor air temperature sensor 25, the indoor piping temperature sensor 23, and the humidity sensor 21. Te and the indoor relative humidity Hr are respectively detected.

In the next step S2, the room temperature Tr
Is different from a predetermined value t1 (for example, 0.5 K). If the difference temperature is larger than the predetermined value t1, the cooling operation is performed in step S3, while the cooling operation is performed. In this case, a dehumidifying operation is performed in step S4.

When the dehumidifying operation is started, in step S5, the temperature difference between the room temperature Tr and the set temperature Ts (Tr-Ts).
Is compared with a predetermined value t2 (for example, 1.5K) larger than t1, and if larger than the predetermined value t2, step S3
When the cooling operation is performed while returning to step S3, the process proceeds to step S6 when the cooling operation is smaller than the predetermined value t2.

In step S6, the difference between the room temperature Tr and the set temperature Ts (Tr-Ts) is compared with a predetermined value t3 (for example, -2.5K) smaller than t1, and the predetermined value t
If it is larger than 3, the process returns to step S4 to continue the dehumidifying operation, while if it is smaller than the predetermined value S3 (that is, if the room is too cold), the compressor 6 is stopped in step S7.

In the next step S8, the room temperature Tr
Whether the temperature difference between Tr and the set temperature Ts (Tr-Ts) is the same as t3,
Alternatively, it is compared with a predetermined value t4 which is larger than the predetermined value t4. If the predetermined value t4 is larger than the predetermined value t4, the process returns to step S4 to perform the dehumidifying operation.
The state of F is continued, and the process proceeds to step S9.

In step S9, the difference (Tr-Ts) between the room temperature Tr and the set temperature Ts is compared with a predetermined value t5 (for example, -3.0K). If the difference is larger than the predetermined value t5, the process proceeds to step S10. I do.

In step S10, it is determined whether or not the indoor relative humidity Hr is within a predetermined range (for example, 40% ≦ Hr <70%). If the indoor humidity Hr is within the predetermined range, the outside air temperature To is compared with a predetermined value t6 (for example, 1 ° C.) in the next step S11. Te is compared with a predetermined value t7 (for example, 15 ° C.), and the continuous duration T _OFF1 in the OFF region of the compressor 6 is compared with a predetermined value T1 (for example, 10 minutes). If the indoor pipe temperature Te is equal to or higher than the predetermined value t7 and the continuous duration T _OFF is equal to or higher than the predetermined value T1, in step S13, the set temperature Ts is changed to the predetermined value t8 (for example,
28 ° C.), and when it is equal to or less than the predetermined value t8, the process proceeds to step S14.

It should be noted that if YES is determined in the step S9, or from the steps S10 to S1
If NO is determined in any of Steps 3, the process returns to Step S7, and the OFF state of the compressor 6 is continued.

In step S14, the O
The continuous duration time T _{OF F2} in the FF region is compared with a predetermined value T2 (for example, 30 minutes), and if it is equal to or greater than the predetermined value T2, the weak heating operation is performed in step S16.

If the determination in step S14 is NO, in step S15, a predetermined time T
3 (for example, 60 minutes), the ratio of the total time T _SUM of the OFF state of the compressor 6 to the predetermined time T3 is compared with a predetermined value α (for example, 0.7). While performing the weak heating operation in step S16, the predetermined value α
If it is smaller, the process returns to step S7, and the OFF state of the compressor 6 is continued.

The determination in step S15 will be described in more detail with reference to FIG. As shown in FIG.
When the N / OFF operation is repeated, the total time T _SUM of the OFF state of the compressor 6 at the predetermined time T3 up to the present time is (a + b + c). Is determined. When the compressor 6 is started, it is assumed that the compressor 6 is all ON for a predetermined time T3, and
The ON / OFF determination of the compressor 6 is monitored at one-minute intervals from the start.

When the weak heating operation is started in step S16, it is determined in step S17 whether the condition for releasing the control of the weak heating operation is satisfied. If so, the process returns to step S3 to perform the cooling operation. If not, the process returns to step S16 to continue the weak heating operation.

In steps S1 to S16, the determinations in steps S2 to S9 are based on the room temperature T
This is for dividing the operation region in the dehumidification operation mode as shown in FIG. 7 according to the difference temperature (Tr−Ts) between r and the set temperature Ts.

The determinations in steps S9 to S15 indicate conditions for establishing the control of the weak heating operation in the dehumidifying operation mode. In summary, all of the following conditions (1) to (5) are satisfied, and , (6) or (7), the weak heating operation is performed. (1) In the dehumidifying operation mode, the indoor set temperature is higher than the suction temperature by a predetermined value (for example, 3K) or more. (2) The relative humidity in the room is within a predetermined range (for example, 40% or more and less than 70%). (3) The outside air temperature is equal to or higher than a predetermined value (for example, 1 ° C.). (4) In the OFF region of the compressor, the indoor pipe temperature continuously exceeds a predetermined value (for example, 15 ° C.) for a predetermined time (for example, 1 ° C.).
0 minutes). (5) The indoor set temperature by the remote control is a predetermined value (for example,
28 ° C) or less. (6) The continuous continuation time of the compressor 6 in the OFF region is equal to or longer than a predetermined value (for example, 30 minutes). (7) The total time of the OFF state of the compressor 6 for a predetermined time (for example, 60 minutes) up to the present is equal to or more than a predetermined ratio (for example, 70%) of the predetermined time.

Here, in the weak heating operation, the compressor 6
Is set to the minimum value (frequency No. in FIG. 3 is 1), and the air volume of the indoor blower is also set to the minimum value. In addition, the vertical wind direction changing blades provided below the suction grille of the indoor unit 4 are set substantially horizontally.

FIGS. 8 to 10 show the operating states of the compressor 6 and the indoor blower after shifting from the dehumidifying operation region to the compressor OFF region.

As shown in FIG. 8, when the operation is shifted to the compressor OFF region, the indoor blower is stopped for a predetermined time, the indoor blower is operated, and after a predetermined time, the heating operation is performed.
Condensed water adhering to the indoor heat exchanger after the dehumidifying operation can be naturally evaporated or drained, and the dehumidifying operation with less re-evaporation can be performed.

FIG. 9 shows a comparative example, in which the compressor OF
In region F, the indoor blower is stopped together with the compressor, and the compressor and the indoor blower are operated simultaneously with the heating operation. In this case, the condensed water adhering to the indoor heat exchanger is re-evaporated at the same time as the heating operation, and may cause occupants to feel uncomfortable.

FIG. 10 shows a modification of the operating state of FIG. 8, and as shown in FIG.
After shifting to the area and stopping the indoor blower for a predetermined time, when starting the heating operation, the activation of the compressor may be delayed for a predetermined time.

Further, as shown in FIG. 10 (b), the operation is shifted to the compressor OFF region, and after stopping the indoor blower for a predetermined time, the indoor blower is turned on / off (intermittent operation).
Heating operation can also be performed.

In the control release determination of the weak heating operation in step S17, if any one of the following conditions (1) to (7) is satisfied, it is determined that the release condition is satisfied. (1) When the OFF point of the compressor 6 is exceeded. (2) When entering a region other than the weak heating region due to temperature change by the remote controller. (3) The indoor set temperature by the remote control is a predetermined value (for example,
29 ° C) or higher. (4) The relative humidity in the room is less than a predetermined value (for example, 40%). (5) The outside air temperature is lower than a predetermined value (for example, 0 ° C.). (6) The weak heating operation is continuously performed for a predetermined time (for example, 30
Min) If you continue. (7) When the relative humidity in the room continues for more than a predetermined value (for example, 70%) for a predetermined time (for example, 1 minute) during the weak heating operation.

In the above embodiment, when the automatic operation mode is selected, as shown in FIG. 11, if the heating, dehumidification and cooling operations are automatically set in accordance with the outside air temperature, the operability and the comfort are further improved. improves. That is, in the automatic operation mode, when the outside air temperature is lower than the first set temperature (for example, 15 ° C.), the heating operation is performed, and on the other hand, the second set temperature (for example, 35 ° C.) in which the outside air temperature exceeds the first set temperature. C)), the cooling operation is performed, and when the outside air temperature is between the first and second set temperatures, the dehumidifying operation is performed. Comfortable air conditioning can be achieved.

[0049]

Since the present invention is configured as described above, it has the following effects. According to the first to fifth aspects of the present invention, when the dehumidifying operation mode is selected, the cooling operation, the dehumidifying operation, and the heating operation are performed in accordance with the temperature difference between the suction temperature and the indoor set temperature. Since one of them is selected, it is possible to provide an air conditioner with improved comfort that can exhibit sufficient dehumidifying ability while maintaining the room temperature set by the occupant.

Further, since the compressor OFF area is provided between the dehumidifying operation area and the heating operation area in the dehumidifying operation mode, frequent repetition of the cooling cycle and the heating cycle can be eliminated, and the dead area can be secured. By doing so, air conditioning with stable control can be performed. Further, it is possible to reduce the generation of unpleasant noise when the refrigeration cycle changes, and it is possible to suppress a rapid change in room temperature.

Further, according to the first aspect of the present invention,
Since the heating operation is performed after a lapse of a predetermined time after the shift from the dehumidifying operation region to the compressor OFF region, the re-evaporation of the dew condensation water adhered to the indoor heat exchanger after the dehumidifying operation can be suppressed, which is comfortable. The performance is improved.

According to the second aspect of the present invention, after shifting from the dehumidifying operation region to the compressor OFF region, the heating operation is performed when the ratio of the total time of the compressor OFF state is equal to or more than a predetermined value. As a result, the dew water adhering to the indoor heat exchanger after the dehumidifying operation can be naturally evaporated or drained, and the re-evaporation of the dew water can be suppressed.

According to the third aspect of the present invention, after shifting from the dehumidifying operation region to the compressor OFF region, the indoor blower is stopped, and after the indoor blower is operated, the heating operation is performed. , The condensation water adhering to the indoor heat exchanger after the dehumidifying operation can be naturally evaporated or drained,
Re-evaporation of dew condensation water can be suppressed.

According to the fourth aspect of the present invention, the indoor blower is stopped for a predetermined time after shifting from the dehumidifying operation region to the compressor OFF region, and the start of the compressor is delayed at the start of the heating operation. In addition, the wind speed of the indoor blower changes according to the pipe temperature, so that the re-evaporation of dew condensation water can be suppressed as much as possible, and the occupant's discomfort of switching from the dehumidifying operation to the heating operation can be eliminated.

According to the fifth aspect of the present invention, after shifting from the dehumidifying operation region to the compressor OFF region, the indoor blower is stopped, and after the operation and stop of the indoor blower are repeated, the heating operation is performed. Since this operation is performed, the dew water adhering to the indoor heat exchanger can be naturally evaporated or drained, and the odor component adhering to the indoor heat exchanger can be prevented from entering the room.

[0056]

[0057]

[0058]

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a refrigeration cycle of an air conditioner employing dehumidification operation control according to the present invention.

FIG. 2 is a control block diagram of a compressor frequency and an electric expansion valve opening in the air conditioner of FIG. 1;

FIG. 3 is a temperature zone division diagram of a temperature difference between a room temperature and a set temperature.

FIG. 4 is a flowchart showing a part of dehumidifying operation control according to the present invention.

FIG. 5 is a flowchart showing another part of the dehumidifying operation control according to the present invention.

FIG. 6 is a time chart showing an ON / OFF state of the compressor.

FIG. 7 is an operation area division diagram showing each operation area in the dehumidification operation mode.

FIG. 8 is a time chart showing the relationship between the operating state of the compressor and the indoor blower and the indoor humidity after shifting from the dehumidifying operation area to the compressor OFF area.

9 is a time chart showing the relationship between the operating state of the compressor and the indoor blower and the indoor humidity as a comparative example of FIG.

FIG. 10 is a time chart showing a modification of FIG. 8, in which (a) shows a case where the start of the compressor is delayed for a predetermined time when starting the heating operation, and (b) shows a start of the heating operation. Each case shows the case where the ON / OFF operation of the indoor blower is performed before the operation.

FIG. 11 is an operation area division diagram when heating, dehumidification, and cooling operations are automatically set in accordance with the outside air temperature in the automatic operation mode.

[Explanation of symbols]

 2 outdoor unit 4 indoor unit 6 compressor 8 outdoor heat exchanger 10 four-way valve 12 indoor heat exchanger 14 liquid side pipe 16 gas side pipe 18 electric expansion valve 21 humidity sensor 22 indoor temperature sensor 23 indoor pipe temperature sensor 24 operation setting circuit 25 outside air temperature sensor 28 room temperature detection circuit 30 differential temperature calculation circuit 32 setting determination circuit 34 ON-OFF determination circuit 36 rated capacity storage circuit 42 compressor frequency calculation circuit 44 expansion valve opening calculation circuit 46 load coefficient table 50 valve initial opening Degree table

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tokuya Asada 1006 Kadoma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Inventor Kenji Shirai 1006 Odaka Kadoma Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. (56) References JP-A-10-103739 (JP, A) JP-A-7-324841 (JP, A) JP-A-63-150550 (JP, A) (58) Fields investigated (Int. ⁷ , DB name) F24F 11/02 102 F24F 11/02

Claims (5)

(57) [Claims] In an air conditioner capable of cooling, dehumidifying, and heating operations, when a dehumidifying operation mode is selected, a suction temperature of an indoor unit is compared with an indoor set temperature, and a comparison is made between the suction temperature and the indoor set temperature. Depending on the temperature difference, while selecting one of the cooling operation, the dehumidifying operation, and the heating operation, providing a compressor OFF region between the dehumidifying operation region and the heating operation region in the dehumidification operation mode, and, A dehumidification control method for an air conditioner, wherein a heating operation is performed after a lapse of a predetermined time after a transition from the dehumidification operation region to the compressor OFF region. 2. An air conditioner capable of cooling, dehumidifying, and heating operations, when a dehumidifying operation mode is selected, compares the suction temperature of an indoor unit with an indoor set temperature and compares the suction temperature with the indoor set temperature. Depending on the temperature difference, while selecting one of the cooling operation, the dehumidifying operation, and the heating operation, providing a compressor OFF region between the dehumidifying operation region and the heating operation region in the dehumidification operation mode, and, After shifting from the dehumidifying operation region to the compressor OFF region, an air conditioner that performs a heating operation when a ratio of the total time of the compressor OFF state in a predetermined time and the predetermined time is equal to or more than a predetermined value. Dehumidification control method. 3. An air conditioner capable of cooling, dehumidifying, and heating operations, when a dehumidifying operation mode is selected, compares the suction temperature of an indoor unit with an indoor set temperature, and compares the suction temperature with the indoor set temperature. Depending on the temperature difference, while selecting one of the cooling operation, the dehumidifying operation, and the heating operation, providing a compressor OFF region between the dehumidifying operation region and the heating operation region in the dehumidification operation mode, and, A dehumidification control method for an air conditioner, wherein the indoor blower is stopped for a predetermined time after the compressor is shifted from the dehumidification operation region to the compressor OFF region, and the indoor blower is operated to perform a heating operation. 4. An air conditioner capable of cooling, dehumidifying, and heating operations, when a dehumidifying operation mode is selected, compares the suction temperature of an indoor unit with an indoor set temperature, and compares the suction temperature with the indoor set temperature. Depending on the temperature difference, while selecting one of the cooling operation, the dehumidifying operation, and the heating operation, providing a compressor OFF region between the dehumidifying operation region and the heating operation region in the dehumidification operation mode, and, A dehumidification control method for an air conditioner in which an indoor blower is stopped for a predetermined time after a shift from the dehumidification operation region to the compressor OFF region, and activation of the compressor is delayed at the start of a heating operation. 5. An air conditioner capable of cooling, dehumidifying, and heating operations, when a dehumidifying operation mode is selected, compares the suction temperature of an indoor unit with an indoor set temperature, and compares the suction temperature with the indoor set temperature. Depending on the temperature difference, while selecting one of the cooling operation, the dehumidifying operation, and the heating operation, providing a compressor OFF region between the dehumidifying operation region and the heating operation region in the dehumidification operation mode, and, A dehumidification control method for an air conditioner, wherein the indoor blower is stopped for a predetermined time after the compressor is shifted from the dehumidification operation region to the compressor OFF region, and the operation and stop of the indoor blower are repeated, and then the heating operation is performed.