JPH06307720A - Controlling method for air conditioner - Google Patents

Abstract

PURPOSE:To prevent abnormal heating of an electronic component by making clear the cause of an operation of an overload protection function of an air conditioner when it operates and also by suppressing restart of a compressor. CONSTITUTION:When a cooling operation is started, the operating time of a compressor is measured (steps ST1 to ST3). When the measurement of the operating time is ended, it is determined whether the compressor is stopped by an overload protection operation or a normal control operation (step ST4). In the case when it is stopped by the overload protection operation, it is determined whether the operating time measured previously is a prescribed value or above or not. When it is the prescribed value or above, the temperature of an outdoor heat exchanger is read in, an outdoor blower is operated then, the temperature of the outdoor heat exchanger is read in again after a prescribed time passes, and then the operation of the outdoor blower is stopped (steps ST5 to ST10). When a temperature difference of the outdoor heat exchanger based on data read before and after the operation of the outdoor blower is a prescribed value or below, information that the outdoor blower is abnormal is given from an informing part and a flag for preventing restart of the compressor is set up (ST11 to ST13).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control method for an air conditioner, and more particularly to investigation of causes when an overload protection function operates.

[0002]

2. Description of the Related Art An air conditioner is composed of an indoor unit and an outdoor unit. The indoor unit has an indoor unit control unit for controlling an indoor blower, a wind direction control plate, etc., and the outdoor unit has a compressor and a four-way unit. There is an outdoor unit controller that controls valves, throttle means, outdoor blowers, etc.
The outdoor unit controller and the indoor unit controller are connected by a signal line. By the way, when the air conditioner is overloaded, not only the compressor is adversely affected, but also the electronic components of the outdoor unit controller may be abnormally heated and damaged. To prevent such accidents, for example, a temperature switch is provided on a heat sink to which electronic parts such as a transistor module are attached, and the operation of the temperature switch is used to interrupt the electric circuit to overload the compressor and electronic parts. It is designed to protect you.

[0003]

However, even in the air conditioner having the above-mentioned overload protection function,
When the overload function actually operates, there is no means for notifying the cause, and there is a problem that it takes time to investigate the cause. Therefore, it is an object of the present invention to provide an air conditioner control method capable of reducing the above-mentioned problems.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and provides an air conditioner configured to protect a compressor, an outdoor unit controller, etc. from an overload state. When the compressor stops due to overload protection operation, the outdoor blower is driven during the stop, and the abnormality of the outdoor blower is detected by the temperature difference between the outdoor heat exchanger before the operation and after the lapse of a predetermined time after the start of operation, and the compression is performed. In addition to not restarting the machine, the notification unit on the indoor unit side notifies that there is an abnormality in the outdoor blower.

[0005]

With the above control method, when the compressor stops due to the overload protection operation, the outdoor blower is driven to cool the outdoor heat exchanger while the compressor is stopped, but the outdoor blower operates normally. If the operation is performed, the temperature difference between the outdoor heat exchanger before the operation and after a lapse of a predetermined time after the operation starts becomes large, and if there is an abnormality in the outdoor blower, it is difficult to make the temperature difference. An abnormality can be detected, and when the outdoor blower is abnormal, the compressor is not restarted, so that abnormal heat generation of electronic components can be prevented. Further, since the alarm unit on the indoor unit side notifies that there is an abnormality in the outdoor blower, it is possible to know the cause of the overload protection operation.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 is an outdoor unit of an air conditioner including an indoor unit and an outdoor unit, 1 is a base, 2 is a box, and 3 is a base 1.
This is a partition plate that divides the inside of the main body consisting of the box body 2 into a heat exchanger chamber 4 and a machine chamber 5. An outdoor heat exchanger 6 and an outdoor blower (propeller fan) 7 are arranged in the heat exchanger chamber 4, a compressor 8 and others are arranged in the lower part of the machine chamber 5, and an electric parts box 9 is protected in the upper rear part. An outdoor unit controller 10 for controlling the outdoor blower 7, the compressor 8 and the like is arranged.
The one side of the electric component box 9 is slightly more heat-exchanger chamber 4 than the partition plate 3.
The heat sink 11 has a transistor module, a temperature switch, etc., which is projected to the side.
A heat sink cover 12 for introducing air in the electric component box 9 is attached to the heat sink 11.
As for the temperature switch attached to the heat sink 11, the compressor 8 and the like are overloaded, and the outdoor heat exchanger 6 and the heat sink 11 cannot be air-cooled due to the abnormality of the outdoor blower 7, and the temperature of the heat sink 11 abnormally rises. It is sometimes activated and used to protect electronic components such as transistor modules from overload conditions (overcurrent).

By the way, in this air conditioner, when the compressor 8 is stopped during the cooling operation, it is possible to determine whether the compressor 8 is stopped by the overload protection operation or the normal control operation. When the outdoor blower 7 is stopped due to the overload protection operation, it is determined whether the cause is the outdoor blower 7, and when the outdoor blower 7 is abnormal, the compressor 8 is not restarted and is not shown. An alarm unit provided on the indoor unit side notifies that the outdoor blower 7 is abnormal. FIG. 2 is a flowchart showing this control operation. When the cooling operation is started, a timer for measuring the operation time of the compressor 8 is started in step ST1. When the stop of the compressor 8 is confirmed in step ST2, the process proceeds to step ST3 and the timer is stopped. In step ST4, it is determined whether the compressor 8 is stopped by the overload protection operation, and if it is found that the compressor 8 is stopped by the normal control operation, the process proceeds to step ST14, and the normal control operation is repeated.

If it is found in step ST4 that the compressor 8 has been stopped due to the overload protection operation, the process proceeds to step ST5, but here, the operating time of the compressor 8 measured previously becomes a predetermined value or more. If it is less than or equal to a predetermined value, the work after step ST6 may become uncertain, so the process proceeds to step ST14, but when the operating time of the compressor 8 is more than the predetermined value Then, the process proceeds to step ST6. In step ST6, the temperature of the outdoor heat exchanger 6 is read, and in the next step ST7, the operation of the outdoor blower 7 is started. This outdoor blower 7 is operated for a predetermined time,
When it is found in step ST8 that the operating time has elapsed, the process proceeds to step ST9, the temperature of the outdoor heat exchanger 6 is read, and the operation of the outdoor blower 7 is stopped in step ST10. In step ST11, it is determined whether or not the temperature difference of the outdoor heat exchanger 6 obtained from the data read before and after the operation of the outdoor blower 7 is less than or equal to a predetermined value. If the temperature difference is equal to or less than the predetermined value, the outdoor blower 7 is abnormal and the outdoor heat exchanger 6 cannot be air-cooled, and the process proceeds to step ST12. In step ST12, the notification unit on the indoor unit side notifies that the outdoor blower 7 is abnormal, and in step ST13, a flag for stopping the restart of the compressor 8 is set.

[0009]

In the air conditioner having the control function as described above, whether the operation stop of the compressor is due to the overload protection operation or the normal control operation, Furthermore, if it is due to the overload protection operation, it is accurately judged whether the cause is due to the abnormality of the outdoor blower, and if there is an abnormality in the outdoor blower, the notification unit will notify. This helps to know the cause of the load protection operation, and also prevents the compressor from being restarted, preventing abnormal heat generation of electronic parts such as a transistor module and improving safety.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an outdoor unit according to the present invention.

FIG. 2 is a flowchart showing an example of a control operation of the present invention.

[Explanation of symbols]

 1 Base 2 Box Body 3 Partition Plate 4 Heat Exchanger Room 5 Machine Room 6 Outdoor Heat Exchanger 7 Outdoor Blower 8 Compressor 9 Electrical Parts Box 10 Outdoor Unit Control Unit 11 Heat Sink 12 Heat Sink Cover

Claims (2)

[Claims] 1. An air conditioner configured to protect a compressor, an outdoor unit control unit, etc. from a normal overload state, and when the compressor is stopped due to an overload protection operation, an outdoor blower is driven during the stop. A method for controlling an air conditioner, characterized in that an abnormality of an outdoor blower is detected based on a temperature difference between an outdoor heat exchanger before operation and after a lapse of a predetermined time after the operation is started, and a compressor is not restarted. 2. When the temperature difference of the outdoor heat exchanger obtained after the overload protection operation is less than or equal to a predetermined value, the informing unit on the indoor unit side informs that the outdoor blower has an abnormality. Item 2. A control method for an air conditioner according to Item 1.