JP3181116B2 - Air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner for distributing and supplying air for air conditioning to a plurality of rooms by a duct.

[0002]

2. Description of the Related Art In a building or the like having a plurality of rooms, an air conditioner of a type that obtains cool air or warm air by operating a refrigeration cycle and a fan and distributes the obtained air to a plurality of rooms by a duct is used.

[0003] In this air conditioner, a duct has a plurality of branch paths, and a damper is provided in each branch path. Then, the air-conditioning load of each room is obtained, the required air volume corresponding to the air-conditioning load is obtained, and the opening degree of each damper is controlled according to the required air volume. Further, the amount of air flowing through each branch passage is detected, and the speed of the fan is controlled by a predetermined value in a direction in which the sum of the amount of air flowing is equal to the sum of the above-mentioned necessary amounts of air.

[0004]

In such an air conditioner, the air supplied from the duct to each room is used for air conditioning and also for obtaining the ventilation action of each room. However, with this ventilation action, the air conditioning progresses and the air conditioning load of each room decreases, and when it comes to a comfortable state (a state where the temperature reaches the set temperature range), the speed of the fan is reduced and the amount of air blown to each room decreases May be insufficient.

[0005] On the other hand, during cooling, the opening of the damper is reduced as the room temperature decreases, the speed of the fan is reduced, and the amount of blown air is reduced. However, there is a limit in reducing the amount of blown air in order to secure the ventilation function of the room. From that point on, the decrease in the room temperature cannot be suppressed, and the room temperature may be lower than the set room temperature. That is, it is too cold.

[0006] In the case of heating, as the room temperature increases, the opening of the damper is reduced, the speed of the fan is reduced, and the amount of blown air is reduced. However, there is a limit in reducing the amount of blown air to secure the ventilation function of the room, and thereafter, the rise in the room temperature cannot be suppressed, and the room temperature may be higher than the set room temperature. That is, it is too warm. The present invention has been made in consideration of the above circumstances, and an object of the air conditioner of claim 1 is to provide a sufficient ventilation effect of each room while maintaining a comfortable state of each room. It is an object of the air conditioner of claim 2 to be able to prevent too cold or too warm.

[0007]

An air conditioner according to a first aspect of the present invention includes a variable capacity compressor, an outdoor heat exchanger, a pressure reducer,
A heat source unit that has a refrigeration cycle connected to an indoor heat exchanger and a variable speed indoor fan, and that blows out air for air conditioning by operating the compressor and the indoor fan; A means for controlling the capacity of the compressor in accordance with the difference between the two, a duct having a branch to a plurality of rooms, a duct for distributing and blowing the blown air of the heat source unit to each room, and a duct provided in each branch of the duct. A damper for adjusting the amount of blown air, a unit for determining a required air volume of each room according to an air conditioning load of each room, a unit for controlling an opening degree of each damper according to the required air volume, and detecting a ventilation volume of each branch road. Means, means for controlling the speed of the indoor fan so that the sum of these ventilation volumes is equal to the sum of the respective required air volumes, and all of the air conditioning loads of each room have reached the set temperature range, and All of the required airflow When not reached the value, and means for correcting the set outlet temperature on the ability decreasing side.

[0008]

2. A refrigeration cycle to which a variable capacity compressor, an outdoor heat exchanger, a decompressor, and an indoor heat exchanger are connected, and a variable-speed indoor fan, and air-conditioning air is blown by operating the compressor and the indoor fan. A heat source unit for discharging, means for controlling the capacity of the compressor in accordance with the difference between the blown air temperature of the heat source unit and the set blown air temperature, and a branch having a branching path leading to a plurality of rooms. A duct for distributing and supplying the wind, a damper for adjusting the amount of blown air provided in each branch of the duct, a means for obtaining a required air volume of each room according to an air conditioning load of each room, and a damper for each of the dampers according to the required air volume. Means for controlling the degree of opening, means for detecting the amount of air flow in each branch, means for controlling the speed of the indoor fan so that the sum of these air flows becomes equal to the sum of the respective required air volumes, and One of the air conditioning loads is the specified value Means are provided for correcting the set blowout temperature to the capacity decreasing side in the following state, and correcting the maximum value to the increasing side when any of the required airflows reaches the maximum value.

[0009]

In the air conditioner of the first aspect, the capacity of the compressor is controlled in accordance with the difference between the temperature of the blown air from the heat source device and the set temperature of the blown air. The air conditioning load of each room is obtained, the required air volume of each room is obtained from these air conditioning loads, and the opening degree of each damper is controlled according to the required air volume. At the same time, the ventilation amount of each branch passage of the duct is detected, and the speed of the indoor fan is changed so that the sum of the ventilation amounts becomes equal to the sum of the respective required ventilation amounts. Further, when all of the air conditioning loads of each room have reached the set temperature range and none of the required airflows has reached the maximum value, the set blowout temperature is corrected to the capacity reduction side. With this correction, the speed of the indoor fan is increased to increase the amount of air blown to each room.

[0010] In the air conditioner of the second aspect, the capacity of the compressor is controlled in accordance with the difference between the blown air temperature of the heat source unit and the set blown air temperature. The air conditioning load of each room is obtained, the required air volume of each room is obtained from these air conditioning loads, and the opening degree of each damper is controlled according to the required air volume. At the same time, the ventilation amount of each branch passage of the duct is detected, and the speed of the indoor fan is changed so that the sum of the ventilation amounts becomes equal to the sum of the respective required ventilation amounts. Also, when any of the air conditioning loads of each room is at or below a predetermined value, the set outlet temperature is corrected to a capacity decreasing side, and when any of the required airflows reaches the maximum value, the maximum value is increased. Correct to the side.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings. As shown in FIG.
There is a building 1 having R ₁ , R ₂ and R _3, and an indoor unit 2 is installed in an empty space in the building 1.

The indoor unit 2 has an air inlet 3 and an air outlet 4, an indoor heat exchanger 5 is provided inside the air inlet 3, and an indoor fan 6 is provided inside the air outlet 4. . That is, by operating the indoor fan 6, indoor air is sucked into the unit from the air inlet 3 and is blown out of the unit from the air outlet 4 through the indoor heat exchanger 5.

The indoor unit 2 further includes an indoor fan 6.
And an inverter 8 for driving the indoor fan 6. The inverter 8 includes a commercial AC power supply (not shown)
Rectified, converted to a voltage having a frequency corresponding to a command from a controller 30 described later, and output. This output is the driving power for the motor of the indoor fan 6. That is, the speed of the indoor fan 6 changes continuously according to the output frequency F of the inverter 8.

The duct 1 is connected to the air outlet 4 of the indoor unit 2.
0 is connected to one end. This duct 10 has an air outlet 4
For distributing and supplying the air for air-conditioning blown out to the rooms R ₁ , R ₂ and R ₃ .
11 and 11. Connecting the branch passage 11, 11, 11 in the room R _1, R _2, air inlet R _3.

An air flow control unit 12 is provided in each of the branch paths 11, 11, 11. These air volume control units 12
Is a damper 13 for adjusting the amount of blown air and an airflow sensor 14
Having.

As shown in FIG. 2, the opening of the damper 13 changes from zero (fully closed) to fully opened by driving the motor. The air volume sensor 14 includes a propeller that rotates upon receiving ventilation, and a detection element that outputs a signal of a voltage level corresponding to the number of rotations of the propeller, and detects the ventilation volume of the branch path 11. An outdoor unit 20 is installed outside the building 1, and the outdoor unit 20 and the indoor unit 2 are connected by a pair of pipes 15.

The outdoor unit 20 includes the variable capacity compressor 2
1, a four-way valve 22, an outdoor heat exchanger 23, a pressure reducer such as an expansion valve 24, an outdoor fan 25, and an inverter 26.
An outdoor heat exchanger 23 is connected to a discharge port of the compressor 21 via a four-way valve 22, and the outdoor heat exchanger 23 is connected to the indoor heat exchanger of the indoor unit 2 via one of the expansion valve 24 and the pipe 15. 5 is connected. The pipe 1 is connected to the indoor heat exchanger 5.
The suction port of the compressor 21 is connected to the other end of the compressor 5 and the four-way valve 22. That is, the outdoor unit 20 and the indoor unit 2 constitute a heat pump refrigeration cycle, and both units function as heat source devices.

The inverter 26 rectifies the voltage of a commercial AC power supply (not shown), and rectifies the rectified voltage.
Is converted into a voltage having a frequency corresponding to the command of the above and output. This output is the driving power of the motor of the compressor 21. on the other hand,
The controller 30 is provided in the indoor unit 2. A controller 40 is provided in each of the air volume control units 12, 12, 12.

The controller 30 comprises a microcomputer and its peripheral circuits. The controller 30 includes an outlet air temperature sensor 7, an inverter 8, a remote control type operating device (hereinafter, abbreviated as a remote controller) 31, and a four-way valve 2.
2. Connect the motor of the outdoor fan 25, the inverter 26, and the controllers 40, 40, 40. The remote controller 31 is used to set operation conditions such as an operation mode (cooling / heating), blown air temperature, and start / stop of operation.

The controllers 40, 40, 40 are composed of a microcomputer and its peripheral circuits. This controller 4
The damper 13, the air volume sensor 14, and the remote controller 41 are connected to 0, 40, and 40, respectively. These remote controllers 4
1 includes an indoor temperature sensor 42 for detecting an indoor temperature, in addition to a function of instructing start / stop of operation and a function of setting an indoor temperature. The controller 40 has the following functional means.

[1] Means for finding the difference ΔT (= Ta−Ts) between the detected temperature (indoor temperature) Ta of the indoor temperature sensor 42 of the remote controller 41 and the set temperature Ts of the remote controller 41 as the air conditioning load of the corresponding room. .

[2] The obtained air conditioning load ΔT is equal to the set value T ₁ ,
T comfort conditions between _{2 (T 1 ≦ ΔT ≦ T} 2) that is judged whether the state has reached the set temperature range, means for sending a comfort signal to controller 30 if the comfortable state.

[3] Based on the detected air conditioning load, a required air volume Wn of the room is obtained. Note that the required airflow Wn has a predetermined maximum value, and the maximum value is expressed as a percentage with 100 being the maximum value. [4] Means for obtaining the damper opening Q corresponding to the obtained required air flow Wn, and driving the damper 13 to have the damper opening Q. [5] Based on the output of the air flow sensor 14, the corresponding branch 1
Means for detecting the amount of ventilation Wa. [6] Means for informing the controller 30 of the required air volume Wn and the ventilation volume Wa. The controller 30 has the following functional means.

[1] Operation of the compressor 21 (drive of the inverter 26) in accordance with the operation of the remote controller 31,
For controlling the operation of the air conditioner, the switching of the four-way valve 22, and the operation of the indoor fan 6 (the driving of the inverter 8). [2] The difference between the detected temperature Tao of the outlet air temperature sensor 7 and the set outlet air temperature Tso of the remote controller 31 is calculated as the total air conditioning load ΔTo.
(= Tao-Tso). [3] Means for controlling the capacity of the compressor 21 (that is, the output frequency of the inverter 26) according to the obtained total air conditioning load ΔTo. [4] Means for calculating the respective sums Wno and Wao of the respective required air volumes Wn and the respective ventilation volumes Wa notified from the respective controllers 40.

[5] The total airflow amount Wao is equal to the required airflow total Wno
The speed of the indoor fan 6 (that is, the output frequency F of the inverter 8) is set to a predetermined value (for example, ΔF = 0.1
Hz).

[6] A comfortable signal is received from all of the controllers 40 (all of the air conditioning loads ΔT in each room are in a comfortable state), and the required air volume Wn notified from each of the controllers 40 is obtained.
Means for correcting the set blowout temperature Tso by a predetermined value to the capacity decreasing side when none of them has reached 100% of the maximum value. The capacity reduction side is a high temperature side during cooling and a low temperature side during heating. Next, the operation of the above configuration will be described. It is assumed that the cooling or heating operation mode is selected by the remote controller 31, a desired blown air temperature is set, and an operation start operation is performed.

Then, the operation of the outdoor unit 20 and the indoor unit 2 is started, and cool air or warm air is blown from the air outlet 4 of the indoor unit 2. The blown air is distributed and supplied to the rooms R ₁ , R ₂ and R ₃ by the duct 10.

At this time, the air temperature Tao from the indoor unit 2 is detected by the air temperature sensor 7, and the detected temperature Tao
ΔTo between the set air temperature Tso of the remote controller 31 and the total air-conditioning load is obtained.

The capacity of the compressor 21, that is, the output frequency of the inverter 26 is controlled in accordance with the obtained total air conditioning load ΔTo, and the outlet air temperature Tao changes toward the set outlet air temperature Tso. The controllers 40, 40, and 40 execute the control shown in FIG.

The detected temperature (indoor temperature) Ta of the indoor temperature sensor 42 provided on the remote controller 41 and the remote controller 41
Is determined as the air-conditioning load (step 101), and it is determined whether or not the air-conditioning load ΔT is in the comfortable state between the set values T ₁ and T ₂ (T ₁ ≦ ΔT ≦ T ₂ ) (step 101). Step 102). If so, a comfort signal is sent to the controller 30 (step 103).

Based on the air-conditioning load ΔT, the required air volume Wn of the corresponding room is obtained (step 104). Required air volume Wn
Is larger when the air conditioning load ΔT is larger, and becomes smaller as the air conditioning load ΔT becomes smaller. The required air volume Wn is notified to the controller 30 (step 105).

The damper opening Q corresponding to the required airflow Wn is determined (step 106), and the damper 13 is driven to the damper opening Q (step 107). The damper opening Q is expressed in percentage as in the case of the required airflow Wn.
%, It directly matches the value of the required airflow Wn. Based on the output of the air flow sensor 14, the corresponding branch 11
Is detected (step 108). This ventilation amount Wa is notified to the controller 30 (step 109). on the other hand,
The controller 30 performs the control shown in FIG.

First, the set air temperature T of the remote controller 31 is set.
The difference between so and the detected temperature Tao of the outlet air temperature sensor 7 is determined as the total air conditioning load ΔTo (= Tao−Tso) (step
201). The capacity of the compressor 21 (that is, the output frequency of the inverter 26) is controlled according to the obtained total air conditioning load ΔTo (step 202).

The required air volume Wn notified from each controller 40
Is obtained (step 203), and the total sum Wao of the ventilation amount Wa notified from each controller 40 is obtained (step 204).

It is determined whether the total airflow amount Wao is equal to or greater than the required airflow total Wno (step 205). If the total airflow amount Wao has not reached the required airflow total Wno,
The output frequency F of the inverter 8 is changed by ΔF (=
0.1 Hz) (step 206). That is, the speed of the indoor fan 6 is increased, and the amount of blown air from the indoor unit 2 is increased. Even if the total airflow amount Wao reaches the required airflow total Wno, if the total airflow amount Wao does not fall within a stable range within a certain range (NO in step 207), the output frequency F at that time is changed by one step ΔF ( = 0.1 Hz) (step 208).

During operation, the reception of a comfort signal from each controller 40 is confirmed (step 209). Here, when the comfort signals are received from all the controllers 40, it is determined whether or not each required airflow Wn has a maximum value of 100% (step 210).
).

When there is no maximum value of 100% (step 210)
NO), the set outlet temperature Tso is corrected by a predetermined value toward the capacity decreasing side. That is, during cooling, the set outlet temperature Tso is set to the predetermined value X.
(Steps 211 and 212), and lowers the set outlet temperature Tso by a predetermined value Y during heating (steps 211 and 213).

When the set outlet temperature Tso increases during cooling,
The total air conditioning load Tso decreases, and the capacity of the compressor 21 decreases. When the capacity decreases, the room temperature (detection temperature of the room temperature sensor 42) Ta of each room rises and the air conditioning load ΔT increases, so that the required airflow Wn of each room increases to compensate for this. When the required airflow Wn increases, the opening degree of the damper 13 changes in the increasing direction, and the speed of the indoor fan 6 changes in the increasing direction, so that the airflow to each room increases. Therefore, sufficient ventilation of each room is ensured.

When the set outlet temperature Tso decreases during heating,
The total air conditioning load Tso decreases, and the capacity of the compressor 21 decreases. When the capacity decreases, the room temperature (detection temperature of the room temperature sensor 42) Ta of each room decreases, and the air conditioning load ΔT increases, so that the required airflow Wn of each room increases to compensate for this. When the required airflow Wn increases, the opening degree of the damper 13 changes in the increasing direction, and the speed of the indoor fan 6 changes in the increasing direction, so that the airflow to each room increases. Therefore, sufficient ventilation of each room is ensured.

Thereafter, when any one of the required airflows Wn reaches the maximum value of 100%, the correction is canceled and returns to the original set blowout temperature Tso (step 214), and the increase in the airflow is terminated. If no comfort signal is received from any of the controllers 40 (NO in step 209), the original set outlet temperature Tso is used (step 214). A second embodiment of the present invention will be described. First, the controller 40 has the following functional means.

[1] Means for obtaining the difference ΔT (= Ta−Ts) between the detected temperature (indoor temperature) Ta of the indoor temperature sensor 42 of the remote controller 41 and the set temperature Ts of the remote controller 41 as the air conditioning load of the corresponding room. .

[2] It is determined whether the obtained air conditioning load ΔT is in a state of being less than a predetermined value (ΔT <T ₀ ), that is, in a so-called excessively reduced state. means. [3] Based on the detected air conditioning load, the required air volume Wn of the room
Ask for. [4] When the air volume up signal is received from the controller 30, the required air volume Wn obtained above is increased by α% (= Wn · α / 100).
) Means to correct only. [5] Means for determining the damper opening Q corresponding to the determined required airflow Wn and driving the damper 13 to achieve the damper opening Q. [6] Based on the output of the air flow sensor 14, the corresponding branch 1
Means for detecting the amount of ventilation Wa. [7] Means for informing the controller 30 of the required air volume Wn and the ventilation volume Wa. The controller 30 has the following functional means.

[1] Operation of the compressor 21 (drive of the inverter 26) in accordance with the operation of the remote controller 31,
For controlling the operation of the air conditioner, the switching of the four-way valve 22, and the operation of the indoor fan 6 (the driving of the inverter 8). [2] The difference between the detected temperature Tao of the outlet air temperature sensor 7 and the set outlet air temperature Tso of the remote controller 31 is calculated as the total air conditioning load ΔTo.
(= Tao-Tso). [3] Means for controlling the capacity of the compressor 21 (that is, the output frequency of the inverter 26) according to the obtained total air conditioning load ΔTo. [4] Means for calculating the respective sums Wno and Wao of the respective required air volumes Wn and the respective ventilation volumes Wa notified from the respective controllers 40.

[5] The total airflow amount Wao is the required airflow total amount Wno
The speed of the indoor fan 6 (that is, the output frequency F of the inverter 8) is set to a predetermined value (for example, ΔF = 0.1
Hz).

[6] When an excess capacity signal is received from at least one of the controllers 40 (at least one air conditioning load ΔT in each room is below a predetermined value), the set outlet temperature Tso is shifted to the capacity decreasing side. Means for correcting by a predetermined value. The capacity reduction side is a high temperature side during cooling and a low temperature side during heating.

[7] When correcting the set outlet temperature Tso, the required airflow Wn of any of the controllers 40 is set to the maximum value 1
Means for sending an air volume up signal to the controller 40 when it reaches 00%. The operation of the above configuration will be described.

First, as shown in the flowchart of FIG. 4, the controllers 40, 40, and 40 determine the air-conditioning load ΔT in step 101, and then the air-conditioning load ΔT is equal to or less than a predetermined value (ΔT <T ₀ ). (Step 301)
). If not, an overcapacity signal is sent to the controller 30 (step 302). That is, the steps of the first embodiment
Steps 301 and 302 are provided in place of 102 and 103.

After obtaining the required airflow Wn based on the air conditioning load ΔT in step 104, it is determined whether or not an airflow up signal has been received from the controller 30 (step 303). Upon receiving the air volume up signal, the obtained required air volume Wn is corrected by α% (= Wn · α / 100) in the increasing direction. That is, steps 303 and 304 are newly provided between steps 104 and 105 of the first embodiment.

After the fan control in steps 207, 208, and 209, the controller 30 confirms whether or not an excessive capacity signal has been received from each controller 40 as shown in the flowchart of FIG. 5 (step 401). Here, when the excess capacity signal is received from at least one of the controllers 40, the set blowing temperature Tso is corrected by a predetermined value to the capacity decreasing side. That is, the set outlet temperature Tso is increased by a predetermined value X during cooling (steps 402 and 403), and the set outlet temperature Ts is set during heating.
o is reduced by a predetermined value Y (steps 402 and 404).

In this way, by correcting the set outlet temperature Tso to the capacity decreasing side, the total air-conditioning load Tso decreases and the capacity of the compressor 21 decreases. Therefore, excessive cooling is prevented during cooling, and excessive heating is prevented during heating.

When the capacity of the compressor 21 decreases, in a room that has not been too cold or too warm, insufficient cooling capacity and insufficient heating capacity will occur. When the cooling capacity or the heating capacity is insufficient, the required air volume Wn is increased by increasing the air conditioning load ΔT, whereby the opening degree of the damper 13 and the speed of the indoor fan 6 are each increased, and the air volume to each room is reduced. Will be up. However, when the required airflow Wn of each room reaches the maximum value of 100%, the damper 13 corresponding to the room is already fully opened, and the increase in the airflow to that room is limited.

Then, it is determined whether or not the required air volume Wn has reached the maximum value 100% (step 405), and if it has been reached, an air volume up signal is sent to the controller 40 which determines the required air volume Wn (step 406). . As described above, the controller 40 that has received the air volume increase signal outputs the required air volume Wn.
Is corrected to α on the increasing side.

When the required air volume Wn is corrected to the increasing side, the total required air volume Wno increases and the speed of the indoor fan 6 increases.
Therefore, even if the damper 13 is fully opened, the air volume to the room is increased, and the lack of ability such as not to cool and not to warm is solved.

[0054]

As described above, according to the present invention,

In the air conditioner of the first aspect, when all of the air conditioning loads in each room have reached the set temperature range and none of the required airflows has reached the maximum value, the set blowout temperature is adjusted to the capacity. Since the speed of the indoor fan is increased by compensating for the decreasing side, the sufficient ventilation action of each room can be obtained while maintaining the comfortable state of each room.

In the air conditioner according to the second aspect, when any of the air conditioning loads in each room is at or below a predetermined value, the set blowout temperature is corrected to the capacity decreasing side, and any of the required air flows is set to the maximum. When the maximum value is reached, the maximum value is corrected to the increasing side, so that it is possible to prevent overcooling or overheating, and also prevent problems such as uncooled and unwarmed.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of each embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation of each controller 40 in the first embodiment.

FIG. 3 is a flowchart for explaining the operation of the controller 30 in the first embodiment.

FIG. 4 is a flowchart for explaining the operation of each controller 40 in the second embodiment.

FIG. 5 is a flowchart for explaining the operation of a controller 30 in the second embodiment.

[Explanation of symbols]

R _1, R _2, R ₃ ... rooms, 2 ... indoor unit, 5 ... indoor heat exchanger, 6 ... indoor fan, 12 ... air volume control unit,
13 damper, 14 air flow sensor, 21 variable capacity compressor, 23 outdoor heat exchanger, 30 controller, 40 controller.

Claims (2)

(57) [Claims] 1. A refrigeration cycle to which a variable capacity compressor, an outdoor heat exchanger, a decompressor, and an indoor heat exchanger are connected, and a variable-speed indoor fan, and air conditioning air is blown by operating the compressor and the indoor fan. A heat source device for discharging, means for controlling the capacity of the compressor in accordance with the difference between the blown air temperature of the heat source device and the set blown air temperature; A duct for distributing and supplying the blow-off air, a damper for adjusting the blow-off air flow provided in each branch of the duct, a means for obtaining a required air flow for each room according to the air conditioning load of each room, Means for controlling the opening degree of each damper, means for detecting the amount of air flow in each of the branch paths, and controlling the speed of the indoor fan so that the sum of these air flows becomes equal to the sum of each of the necessary air volumes. Means and each said room Means for correcting the set blowout temperature to a capacity decreasing side when all of the air conditioning loads of the air conditioner have reached the set temperature range and none of the required airflows has reached the maximum value. An air conditioner characterized by increasing the speed of the indoor fan to increase the amount of air blown to each room. 2. A refrigeration cycle to which a variable capacity compressor, an outdoor heat exchanger, a decompressor, and an indoor heat exchanger are connected, and a variable-speed indoor fan, and air-conditioning air is blown by operating the compressor and the indoor fan. A heat source device for discharging, means for controlling the capacity of the compressor in accordance with the difference between the blown air temperature of the heat source device and the set blown air temperature; A duct for distributing and supplying the blow-off air, a damper for adjusting the blow-off air flow provided in each branch of the duct, a means for obtaining a required air flow for each room according to the air conditioning load of each room, Means for controlling the opening degree of each damper, means for detecting the amount of air flow in each of the branch paths, and controlling the speed of the indoor fan so that the sum of these air flows becomes equal to the sum of each of the necessary air volumes. Means and each said room When any of the air conditioning loads is below a predetermined value, the set outlet temperature is corrected to the capacity decreasing side, and when any of the required airflows reaches the maximum value, the maximum value is corrected to the increasing side. And an air conditioner.