US20160109161A1

US20160109161A1 - Air conditioning apparatus

Info

Publication number: US20160109161A1
Application number: US14/889,258
Authority: US
Inventors: Tohru ARIGA
Original assignee: Sharp Corp
Current assignee: Sharp Corp
Priority date: 2013-06-18
Filing date: 2014-02-18
Publication date: 2016-04-21
Also published as: CA2911492A1; JP2015001354A; JP5676691B2; WO2014203559A1

Abstract

When the outside air temperature is low, an air conditioner 1 performs a heating operation while a heating unit 2 performs a main heating operation. When the outside air temperature is high, the air conditioner 1 performs a main heating operation, and the heating unit 2 performs an auxiliary heating operation. While the air conditioner 1 performs a heating operation, the heating unit 2 is turned off before the room temperature reaches a set temperature. That is, the heating unit 2 is turned on for a longer time as the outside air temperature becomes lower. In this way, the heating unit 2 is operated under the situation to thereby supplement the heating capacity of the air conditioner 1, so that comfortable heating is performed.

Description

TECHNICAL FIELD

The present invention relates to an air conditioning apparatus which performs heating by an air conditioner and a heating device.

BACKGROUND ART

During a heating operation of an air conditioner, when the outside air temperature is low, the heating capacity of the air conditioner is insufficient. In order to supplement the lack of heating capacity, a heater is provided as an auxiliary heating device, as described in Patent Literature 1. When the outside air temperature is low, the heater performs a heating operation at the same time when the air conditioner performs a heating operation by performing a refrigeration cycle. By the operation of the heater, it is possible to supplement the lack of heating capacity of the air conditioner.

CITATION LIST

Patent Literature

Patent Literature 1: Japanese Patent Laid-Open No. 2000-304331

SUMMARY OF INVENTION

Technical Problem

When a heating operation is performed by the air conditioner, the heater is operated simultaneously with the operation of the air conditioner, but the heater is turned on and off so as to prevent the heating capacity from becoming larger than required. That is, in the case where the heating operation is performed by the air conditioner, after the room temperature is increased to reach a set temperature, the compressor of the air conditioner is stopped, and the heater is also turned off. When the room temperature is reduced, the air conditioner and the heater are turned on. The heater is turned on, and thereby the room temperature is increased. For this reason, the compressor of the air conditioner and the heater are frequently turned on and off, as a result of which electric power is unnecessarily consumed, and energy saving cannot be achieved.
In view of the above, it is an object of the present invention to provide an air conditioning apparatus capable of providing comfortable heating in such a manner that the heating capacity of an air conditioner is supplemented by operating a heating device according to the situation.

Solution to Problem

The air conditioning apparatus of the present invention is configured by an air conditioner performing an air conditioning operation by driving a compressor, and a heating device operating in conjunction with the air conditioner, and is configured such that, when an outside air temperature is lower than a first predetermined temperature, the air conditioner performs heating operation while the heating device performs a main heating operation, and such that, when the outside air temperature is not lower than the first predetermined temperature, the air conditioner performs a main heating operation, and the heating device performs an auxiliary heating operation.
When the outside air temperature is lower than the first predetermined temperature (when the outside air temperature is low), the heating capacity of the air conditioner is low, and hence the heating device performs a main heating operation. When the outside air temperature is not lower than the first predetermined temperature (when the outside air temperature is high), the heating capacity of the air conditioner is also high, and hence the heating device performs a heating operation to supplement the heating provided by the air conditioner. In this way, the heating device supplements the heating according to the situation, so that the room temperature is quickly increased. Thereby, the room temperature can reach a set temperature in a short time, so that it is possible to achieve energy saving.
It is preferred that, during the heating operation of the air conditioner, the heating device is turned off before the room temperature reaches the set temperature. Thereby, after the heating device is turned off, only the air conditioner performs the heating operation, so that the room temperature can be prevented from being changed.
It is preferred that a stop temperature, at which the heating device is turned off during a heating operation, is set according to the outside air temperature, and that the difference between the set temperature and the stop temperature decreases as the outside air temperature becomes lower. Thereby, as the outside air temperature decreases, the heating device can more sufficiently supplement the low heating capacity of the air conditioner, so that the room temperature can be quickly increased.
It is preferred that the air conditioner performs a heating operation in a manner that the number of revolutions of the compressor is in a high efficiency range or at a maximum rotational speed. Thereby, the heating capacity of the air conditioner can be maximized, so that the room temperature can be quickly increased.
It is preferred that, when the outside air temperature is lower than a second predetermined temperature, the air conditioner stops a heating operation to perform a blowing operation, and the heating device operates. The second predetermined temperature is lower than the first predetermined temperature. Thereby, when the outside air temperature is lower than the second predetermined temperature, the air conditioner is made not to perform a heating operation in order to protect the air conditioner. In this case, only the heating device performs a heating operation instead of the air conditioner.

Advantageous Effects of Invention

According to the present invention, the heating by the heating device can be effectively used in addition to the heating by the air conditioner, so that the room temperature can be quickly increased. Thereby, the power consumption at the time of heating can be reduced.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a figure showing a configuration of an air conditioning apparatus of the present invention.

FIG. 2 is a schematic representation of a refrigeration cycle of an air conditioner.

FIG. 3 is a control block diagram of the air conditioning apparatus.

FIG. 4 is a figure showing a temperature at which a heating device is stopped at each outside air temperature.

FIG. 5 is a flow chart showing an operation of the air conditioning apparatus at the time of heating.

FIG. 6 shows timings at which the heating device is turned on and off.

DESCRIPTION OF EMBODIMENTS

FIG. 1 shows an air conditioning apparatus of a first embodiment. The air conditioning apparatus is configured by an air conditioner 1 and a heating device 2. As shown in FIG. 2, the air conditioner 1 is configured in such a manner that an indoor unit is connected to an outdoor unit by piping and wiring. The outdoor unit is provided with a compressor 3, a four way valve 4, an outdoor heat exchanger 5, a restriction apparatus 6, and an outdoor fan 7. The indoor unit is provided with an indoor heat exchanger 8 and an indoor fan 9. A refrigeration cycle is formed by the compressor 3, the four way valve 4, the outdoor heat exchanger 5, the restriction apparatus 6, and the indoor heat exchanger 8. It should be noted that an expansion valve is used as the restriction apparatus 6, but a capillary tube, or the like, may also be used.
The heating device 2 is installed in the same room as the indoor unit. It should be noted that the heating device 2 may also be provided in the inside of the air conditioner 1. For example, the heating device 2 is provided in an air supply passage extending from a suction port to a blow-out port in the air conditioner 1.
The air conditioner 1 and the heating device 2 are made communicable with each other, and the heating device 2 is operated by a command of the air conditioner 1. As shown in FIG. 1(a), a repeater 10 is provided between the air conditioner 1 and the heating device 2. The repeater 10 is connected to the air conditioner 1 and the heating device 2. The repeater 10 has a communication function, and the air conditioner 1 and the heating device 2 perform indirect communication via the repeater 10. Alternatively, FIG. 1(b) shows a configuration in which the repeater 10 is connected to the air conditioner 1, and a repeater 10 a is connected to the heating device 2, and in which each of the repeater 10 and the repeater 10 a has a radio communication function or an infrared-ray communication function. It should be noted that the air conditioner 1 and the heating device 2 may directly communicate with each other wirelessly or via a wire without using the repeater 10.
As shown in FIG. 3, the air conditioner 1 is provided with a control apparatus 20 which performs air conditioning operations, such as cooling, heating, and dehumidifying operations, by controlling the refrigeration cycle. The outdoor unit is provided with an outdoor temperature detector 21, such as a thermistor, and the indoor unit is provided with a room temperature detector 22, such as a thermistor. According to a specified air conditioning operation, the control apparatus 20 respectively controls the rotation of the compressor 3, the opening degree of the restriction apparatus 6, the rotation of the outdoor fan 7, and the rotation of the indoor fan 9 on the basis of a temperature detected by each of the temperature detectors 21 and 22.
On the basis of a set temperature set by a user, or a set temperature set beforehand in an automatic operation mode, and on the basis of the detected room temperature and the detected outside temperature, the control apparatus 20 determines the number of revolutions of the compressor 3 to increase the Coefficient Of Performance (COP). Then, the number of revolutions of the indoor fan 9 is determined according to the number of revolutions of the compressor 3. The control apparatus 20 controls the compressor 3 on the basis of the determined number of revolutions, and changes the number of revolutions of the compressor 3 according to the room temperature. Further, the control apparatus 20 controls the indoor fan 9 on the basis of the number of revolutions according to the number of revolutions of the compressor 3.
The heating device 2 is provided with a heater 23 which generates heat by supply of power, and a drive section 24 which switches power supply to the heater 23. The drive section 24 switches power supply to the heater 23, and thereby the heating device 2 is turned on and off. Further, in the heating operation mode of the air conditioning apparatus, the air conditioner 1 controls the operation of the heating device 2 at the time of heating operation. In the case where the repeater 10 is provided between the air conditioner 1 and the heating device 2, when the control apparatus 20 of the air conditioner 1 outputs a drive signal to the heating device 2, the drive signal is transmitted to the heating device 2 via the repeater 10. When receiving the drive signal, the drive section 24 of the heating device 2 turns on and off the power supply according to the drive signal. In the case where a heating operation is performed by the air conditioning apparatus, the control apparatus 20 of the air conditioner 1 turns on the heating device 2 simultaneously with the heating operation. When the room temperature reaches a stop temperature, the control apparatus 20 turns off the heating device 2. The heating device 2 is turned off before the compressor 3 is turned off.
Here, the timing when the heating device 2 is turned off is different according to the outside air temperature. When the outside air temperature is high, the timing of turn off of the heating device 2 is short. On the other hand, when the outside air temperature is low, the timing of turning off of the heating device 2 is long. That is, when the outside air temperature is low, the air conditioner 1 performs heating operation while the heating device 2 performs a main heating operation. When the outside air temperature is high, the air conditioner 1 performs a main heating operation while the heating device 2 performs an auxiliary heating operation. It should be noted that, when the outside air temperature is lower than, for example, −15° C., the air conditioner 1 does not perform a heating operation in order to protect devices such as the compressor 3, but the air conditioner 1 performs a blowing operation and turns on only the heating device 2.
The timing when the heating device 2 is turned off is determined according to the outside air temperature. As shown in FIG. 4, the stop temperature, at which the heating device 2 is turned off, is set to a temperature before the room temperature increased by the heating to reach a set temperature. Specifically, the stop temperature is set lower by a predetermined temperature than the set temperature. As the outside air temperature is lower, the predetermined temperature is set to a smaller value. Therefore, the difference between the set temperature and the stop temperature is more reduced as the outside air temperature is lower.
For example, when the outside air temperature is not lower than 10° C., the stop temperature is set to a set temperature of −4° C. When the outside air temperature is not lower than 5° C. and is lower than 10° C., the stop temperature is set to a set temperature of −3° C. When the outside air temperature is not lower than −5° C. and is lower than 5° C., the stop temperature is set to a set temperature of −2° C. When the outside air temperature is not lower than −15° C. and lower than −5° C. (lower than a first predetermined temperature), the stop temperature is set to a set temperature of −1° C. It should be noted that, when the outside air temperature is lower than −15° C. (lower than a second predetermined temperature), only the heating device 2 is turned on, and the stop temperature is set to the set temperature. Therefore, since, when the outside air temperature is lower than −5° C. which is regarded as a low temperature, the heating capacity of the air conditioner 1 is small, the heating device 2 performs a main heating operation, and the air conditioner 1 performs an auxiliary heating operation. When the outside air temperature is not lower than −5° C. which is regarded as a high temperature, the air conditioner 1 performs a main heating operation while the heating device 2 performs an auxiliary heating operation. Here, an example of how to determine the first predetermined temperature is described. The heating capacity of the air conditioner is lowered as the outside air temperature is lower. The outside air temperature, at which the heating capacity of the air conditioner is lowered to about 60%, is set as the first predetermined temperature. A rough estimate of the outside air temperature is about −8° C., but in the present embodiment, it is set at −5° C. to provide a margin. The first predetermined temperature can be changed according to the performance of the air conditioning apparatus and states of the region where the air conditioning apparatus is used.
It should be noted that the stop temperature may be set beforehand, but the stop temperature may also be changeable. The stop temperature is changed by the user operating a remote controller of the air conditioner 1. Alternatively, the repeater 10 is provided with a temperature switching button, and the user operates the temperature switching button to change the stop temperature.
Further, in the heating operation mode in which the air conditioner 1 performs a heating operation and, at the same time, the heating device 2 is turned on to perform a heating operation, the control apparatus 20 of the air conditioner 1 controls the compressor 3 so that the number of revolutions of the compressor 3 is in a high efficiency range. The number of revolutions in the high efficiency range is a number of revolutions in a predetermined range including the number of revolutions at which COP is a maximum efficiency. When the number of revolutions of the compressor 3 is in this range, the air conditioner 1 can perform a highly efficient operation.
FIG. 5 shows an operation when the above-described air conditioning apparatus performs a heating operation. When the user starts a heating operation mode of the air conditioner 1 by using the remote controller, or the like, the control apparatus 20 detects an outside air temperature by the outside temperature detector 21 (S1).
When the outside air temperature is lower than the second predetermined temperature (−15° C.), the control apparatus 20 of the air conditioner 1 performs a blowing operation while stopping the compressor 3, and turns on the heating unit 2. The air conditioner 1 outputs an on signal to the heating device 2, and then the heating device 2 receives the on signal and is turned on (S2). The heating device 2 performs a heating operation, so that the room temperature is increased. When the air conditioner 1 performs the blowing operation, the control apparatus 20 controls the indoor fan 9 according to the wind velocity set by the user. When the wind velocity is set automatically, the control apparatus 20 controls the indoor fan 9 so that the air is gently blown.
When the outside air temperature is not lower than −15° C., the control apparatus 20 turns on the compressor 3 to start a heating operation, and at the same time, turns on the heating device 2 (S3). In this case, the heating device 2 performs a heating operation, and the air conditioner 1 performs a highly efficient heating operation. The control apparatus 20 confirms the stop temperature of the heating device 2 on the basis of the detected outside air temperature, and checks the room temperature. When the room temperature at the time of starting the heating operation is higher than the stop temperature, the control apparatus 20 does not turn on the heating device 2, so that only the air conditioner 1 performs a heating operation.
When the room temperature is increased to reach the stop temperature (S4), the control apparatus 20 turns off the heating device 2. When the air conditioner outputs an off signal to the heating device 2, the heating device 2 is turned off (S5). The air conditioner 1 continues the heating operation. When the room temperature reaches the set temperature (S6), the control apparatus 20 stops the compressor 3 and performs a blowing operation (S7).
When the room temperature is lower than the set temperature, the control apparatus 20 of the air conditioner 1 turns on the compressor 3 and resumes the heating operation. When the room temperature is lower than the stop temperature, the control apparatus 20 turns on the heating device 2. As shown in FIG. 6, the room temperature, at which the heating device 2 is turned on, is set to a temperature which is lower than the stop temperature by a fixed temperature, for example, 0.5° C.
It should be noted that, when the outside air temperature is changed during the heating operation of the air conditioner 1, the control apparatus 20 changes the stop temperature according to the outside air temperature. On the basis of the changed stop temperature, the control apparatus 20 turns on and off the heating device 2. When the outside air temperature is lower than −15° C., the control apparatus 20 turns off the compressor 3 and stops the heating operation. At this time, when the heating device 2 is turned off, the heating device 2 is turned on.
Further, when the air conditioner 1 performs a heating operation, frost build-up occurs on the outdoor heat exchanger 5. For this reason, the heating operation is stopped and a defrosting operation is performed. At the time of the defrosting operation, the control apparatus 20 repeatedly turns on and off the heating unit 2 to intermittently operate the heating device 2. When the defrosting operation is started, the heating device 2 is turned on. When a fixed time, for example, 3 minutes elapsed, the heating device 2 is turned off. Further, when a fixed time is elapsed, the heating device 2 is turned on. Until the defrosting operation is completed, the control apparatus 20 repeatedly turns on and off the heating device 2. Thereby, the room temperature under the defrosting operation can be prevented from being lowered. Further, by turning on and off the heating device 2, it is prevented that the room temperature becomes too high.
As described above, when the outside air temperature is low, the room temperature is also low, and hence the on-time of the heating device 2 becomes long. In this way, when the heating device 2 performs a main heating operation, and in the situation where the heating capacity of the air conditioner 1 is low, the heating by the heating device 2 is largely used, so that the room temperature can be quickly increased. On the other hand, when the outside air temperature is high, and in the situation where the room temperature is low, heating by the heating device 2 is added to the heating capacity of the air conditioner 1, so that the room temperature can be quickly increased. For this reason, the heating device 2 is turned off sooner, and thereby the on-time of the heating device 2 is turned on is reduced. In addition, the air conditioner 1 can perform a highly efficient heating operation, so that energy saving is achieved. Further, when the room temperature is about the set temperature, the heating device 2 is turned off, and hence the room temperature becomes not too high. For this reason, the compressor 3 can be prevented from being frequently turned on and off, so that stable temperature control can be performed.
When the air conditioner 1 turns on the heating device 2 and performs a heating operation, the air conditioner 1 may drive the compressor 3 at its maximum rotational speed. When the compressor 3 is driven at its maximum rotational speed, the compressor 3 can exhibit a maximum capacity to quickly realize the state where the compressor 3 operates at a high efficiency. As a result, the timing of turning off of the heating unit 2 is reduced, so that energy saving is achieved.
Meanwhile, in order that the air conditioner 1 operates the heating device 2, the air conditioner 1 needs to recognize that the heating device 2 is provided. In the case where the heating device 2 is connected to the air conditioner 1 via the repeater 10, when the control apparatus 20 of the air conditioner 1 detects that a connection terminal is connected to the repeater 10, the control apparatus 20 determines that the heating device 2 is provided. When the control apparatus 20 recognizes the heating device 2, the control apparatus 20 outputs a drive signal to the heating device 2.
As shown in FIG. 1(b), when wireless communication is performed between the two repeaters 10 and 10 a, the air conditioner 1 intermittently outputs a drive signal to the heating device 2. When the heating device 2 is turned on, the control apparatus 20 of the air conditioner 1 outputs an on signal at fixed intervals. For example, the control apparatus 20 outputs the on signal every minute. When the heating device 2 is turned off, the control apparatus 20 outputs an off signal at fixed intervals. For example, the control apparatus 20 outputs the off signal every 10 minutes. When the heating device 2 receives the drive signal from the air conditioner 1, the heating device 2 operates under the command of the finally received drive signal until receiving the next drive signal. Further, even when the air conditioner 1 performs direct wireless communication with the heating device 2, drive signals are outputted periodically in the same manner.
Even when the heating device 2 cannot normally receive a drive signal due to a noise, and the like, the air conditioner 1 continuously communicates with the heating device 2, and thereby the heating device 2 can receive the next drive signal. Therefore, according to the heating operation of the air conditioner 1, the heating device 2 can be surely controlled. Further, the output interval of the drive signal at the time when the heating device 2 is turned off is set longer than the output interval of the drive signal at the time when the heating device 2 is turned on. Thereby, power consumption can be reduced.
As described above, the air conditioning apparatus of the present invention is configured by the air conditioner 1 performing an air conditioning operation by driving the compressor 3, and also configured by the heating device 2 operating in conjunction with the air conditioner 1. When the outside air temperature is lower than the first predetermined temperature, the air conditioner 1 performs a heating operation while the heating device 2 performs a main heating operation, and when the outside air temperature is not lower than the first predetermined temperature, the air conditioner 1 performs a main heating operation as the main heating unit, and the heating device 2 performs an auxiliary heating operation.
When the outside air temperature is low, and when the heating capacity of the air conditioner 1 is low, the heating device 2 performs a main heating operation so that the room temperature is increased to approach the set temperature. When the outside air temperature is high, and when the heating capacity of the air conditioner 1 is high, the air conditioner 1 performs a main heating operation. In this case, when the room temperature is low at the start of operation, and the like, the room temperature can be quickly increased by turning on the heating device 2.
During the heating operation of the air conditioner 1, the heating device 2 is turned off before the room temperature reaches the set temperature. Therefore, in the process in which the room temperature is increased, the heating device 2 is turned off before the compressor is turned off.
That is, when a heating operation is started, the air conditioner 1 and the heating device 2 are simultaneously started, and the heating device 2 is turned off before the room temperature reaches the set temperature. Further, when the outside air temperature is high, the timing of turning off of the heating device 2 is short, while when the outside air temperature is low, the timing of turning off of the heating device 2 is long.
The stop temperature, at which the heating device 2 is turned off during a heating operation, is set according to the outside air temperature. The difference between the set temperature and the stop temperature is reduced as the outside air temperature is lower. Therefore, the heating device 2 is turned on for a longer time as the outside air temperature is lower. When the outside air temperature is low, the room temperature is also low. Therefore, it takes time until the room temperature is increased to the stop temperature. For this reason, the time, during which the heating device 2 is turned on, becomes long. When the outside air temperature is high, the room temperature is also high, and hence the room temperature is increased to reach the stop temperature in a short time. For this reason, the time, during which the heating device 2 is turned on, becomes short.
The air conditioner 1 performs a heating operation in such a manner that the number of revolutions of the compressor 3 is in a high efficiency range, or in such a manner that the compressor 3 is operated at a maximum rotational speed. Thereby, the heating capacity of the air conditioner 1 can be maximized, so that the room temperature can be quickly increased.
When the outside air temperature is lower than the second predetermined temperature, the heating operation of the air conditioner 1 is stopped. That is, the air conditioner 1 stops the compressor 3 to perform a blowing operation, and starts the heating device 2. A failure is caused when the air conditioner 1 performs a heating operation while the outside air temperature is lower than the second predetermined temperature. In this case, a blowing operation can be performed by the air conditioner 1, and hence the air warmed by the heating device 2 can be stirred. As the blowing operation here, a state is assumed in which, while the heating operation mode is continued, the compressor 3 is stopped, and the indoor fan 9 is driven to blow air. It should be noted that the heating operation mode may be stopped so that the blowing operation mode is performed.
When the air conditioner 1 performs a defrosting operation, the heating device 2 intermittently operates. That is, when the defrosting operation is started, the heating device 2 is repeatedly turned on and off at fixed time intervals. When the heating device 2 is turned on, the room temperature can be prevented from being lowered. Further, when the heating device 2 is turned off, the room temperature is also prevented from being increased too high.
The air conditioner 1 and the heating device 2 can communicate with each other indirectly or directly, and the heating device 2 operates according to a command of the air conditioner 1. The air conditioner 1 controls the turning on and off of the heating device 2 according to the room temperature. When the air conditioner 1 starts a heating operation, the heating device 2 is turned on by a command of the air conditioner 1. When the room temperature reaches the stop temperature, the heating device 2 is turned off by a command of the air conditioner 1. In this case, a commercial apparatus can be used without adding a special function to the heating unit 2.
A second embodiment will be described. In the first embodiment, a heating operation by a heat pump in the air conditioner 1, and a heating operation by the heating device 2 are used in combination with each other. However, when the outside air temperature is low, the heating capacity of the air conditioner 1 is low, and hence only the heating device 2 may be operated. Then, when the room temperature has been increased by the heating by the heating device 2, the heating device 2 is turned off, and the air conditioner 1 starts a heating operation. In this case, it is only necessary that the room temperature is slightly increased to reach the set temperature by the air conditioner 1. Therefore, even when the heating capacity of the air conditioner 1 is low, the heating can be efficiently performed.
A third embodiment will be described. In the first and the second embodiments, the one heating device 2 is used, but the number of the heating devices 2 is not limited to one. In the third embodiment, a plurality of the heating devices 2 are provided. At this time, the number of the heating devices 2, which are operated, is determined according to the outside air temperature. When the outside air temperature is low, many numbers of the heating devices 2 are operated. Further, when, during a heating operation, a plurality of the heating devices 2 are turned on, the number of the heating devices 2 which are turned on is reduced as the room temperature is increased. For example, the heating devices 2 are turned off in order as the room temperature approaches the stop temperature. Further, the heating device 2 capable of changing heat generation amounts may also be used. In this case, the amount of heat generated by the heating device 2 is reduced as the room temperature is increased.
A fourth embodiment will be described. In the first to third embodiments, the heating device 2 is controlled by the air conditioner 1, but in the fourth embodiment, the heating device 2 controls turning on and off thereof. When the air conditioner 1 starts a heating operation, the air conditioner 1 outputs, to the heating device 2, information on the start of operation and information on the outside air temperature. The heating device 2 is provided with a room temperature detector, and the heating device 2 turns on itself when receiving these pieces of information. The heating device 2 detects the room temperature. When detecting that the room temperature reaches the stop temperature, the heating device 2 turns off itself.
It should be noted that the present invention is not limited to the above-described embodiments, but numerous modifications and changes can be obviously made therein without departing from the scope of the present invention. As the heating device 2, a heating device using the combustion of gas, kerosene, or the like, may also be used. In each of the embodiments, when the room temperature reaches the set temperature, the air conditioner 1 performs a blowing operation, but the blowing operation may not be performed. Further, the outdoor unit may also be provided with the heating device 2. In this case, the heating device 2 can warm the refrigerant discharged from the compressor 3 and supply the hot refrigerant to the indoor heat exchanger, so that the room temperature can be quickly increased.
At the time of defrosting operation, the on/off timing of the heating device 2 may be changed according to the room temperature. For example, when the room temperature is high, the time during which the heating device 2 is turned off is set to be long, while when the room temperature is low, the time during which the heating device 2 is turned on is set to be long.

REFERENCE SIGNS LIST

- 1 Air conditioner
- 2 Heating device
- 3 Compressor
- 4 Four way valve
- 5 Outdoor heat exchanger
- 6 Restriction apparatus
- 7 Outdoor fan
- 8 Indoor heat exchanger
- 9 Indoor fan
- 10 Repeater
- 20 Control apparatus
- 21 Outside air temperature detector
- 22 Room temperature detector
- 23 Heater
- 24 Drive section

Claims

1-5. (canceled)

6. An air conditioning apparatus configured by an air conditioner performing an air conditioning operation by driving a compressor, and a heating device operating in conjunction with the air conditioner, wherein: when an outside air temperature is lower than a first predetermined temperature, the air conditioner performs a heating operation while the heating device performs a main heating operation; and when the outside air temperature is not lower than the first predetermined temperature, the air conditioner performs a main heating operation, and the heating device performs an auxiliary heating operation.

7. The air conditioning apparatus according to claim 6, wherein, during the heating operation of the air conditioner, the heating device is turned off before the room temperature reaches a set temperature.

8. The air conditioning apparatus according to claim 7, wherein a stop temperature, at which the heating device is turned off during a heating operation, is set according to the outside air temperature, and a difference between the set temperature and the stop temperature decreases as the outside air temperature decreases.

9. The air conditioning apparatus according to claim 6, wherein the air conditioner performs a heating operation so that a number of revolutions of the compressor is in a high efficiency range or at a maximum rotational speed.

10. The air conditioning apparatus according to claim 7, wherein the air conditioner performs a heating operation so that a number of revolutions of the compressor is in a high efficiency range or at a maximum rotational speed.

11. The air conditioning apparatus according to claim 8, wherein the air conditioner performs a heating operation so that a number of revolutions of the compressor is in a high efficiency range or at a maximum rotational speed.

12. The air conditioning apparatus according to claim 6, wherein, when the outside air temperature is lower than a second predetermined temperature, the air conditioner stops a heating operation to perform a blowing operation, and the heating device operates.

13. The air conditioning apparatus according to claim 7, wherein, when the outside air temperature is lower than a second predetermined temperature, the air conditioner stops a heating operation to perform a blowing operation, and the heating device operates.

14. The air conditioning apparatus according to claim 8, wherein, when the outside air temperature is lower than a second predetermined temperature, the air conditioner stops a heating operation to perform a blowing operation, and the heating device operates.

15. The air conditioning apparatus according to claim 9, wherein, when the outside air temperature is lower than a second predetermined temperature, the air conditioner stops a heating operation to perform a blowing operation, and the heating device operates.

16. The air conditioning apparatus according to claim 10, wherein, when the outside air temperature is lower than a second predetermined temperature, the air conditioner stops a heating operation to perform a blowing operation, and the heating device operates.

17. The air conditioning apparatus according to claim 11, wherein, when the outside air temperature is lower than a second predetermined temperature, the air conditioner stops a heating operation to perform a blowing operation, and the heating device operates.