JPH05196275A - Abnormal state judgement device for air conditioner - Google Patents

Abstract

PURPOSE:To stop operation of a compressor and display abnormal state of it when an outdoor heat exchanger temperature sensor shows migration phenomenon during defrosting operation at the time of heating in a room and further when the defrosting operation can not be carried out as the sensor fixing state is poor. CONSTITUTION:An abnormal state judgement device is comprised of a comparing and calculation means for use in comparing and calculating the temperature detected by an indoor heat exchanger temperature sensor 7 of an air conditioner and the predetermined temperature, and a time measuring means for measuring time when the comparing and calculation means judges that the temperature of the indoor heat exchanger temperature sensor 7 is lower than the predetermined temperature, and comparing and calculating it with the predetermined time. As the predetermined time is reached to by the time measuring means, a compressor 1 is stopped, and at the same time an abnormal state displaying lamp 9 is illuminated and an emergency stopping means for informing the abnormal state is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an abnormality judging device for judging abnormal frost formation in an air conditioner.

[0002]

2. Description of the Related Art Conventionally, in a defrosting method for an air conditioner, a sensor mounted near an outdoor heat exchanger detects a temperature and defrost control is performed when a predetermined temperature and a predetermined time are reached. An example of the conventional defrosting method for the air conditioner will be described below with reference to the drawings.

FIG. 5 is a refrigeration cycle diagram of a conventional air conditioner. This air conditioner includes a compressor 1, a four-way valve 2,
It is composed of an indoor heat exchanger 3, an expansion valve 4, and an outdoor heat exchanger 5, and a refrigerant circulates in these parts. Further, 6 is an outdoor heat exchanger temperature sensor, 7 is an indoor heat exchanger temperature sensor, and receives signals from the outdoor heat exchanger temperature sensor 6 and the indoor heat exchanger temperature sensor 7, the compressor 1, The indoor / outdoor fan (not shown), the expansion valve 4 and the like are controlled by the controller 8. Here, during the heating operation in which the outside air temperature is low, the evaporation temperature of the outdoor heat exchanger 5 decreases, and the outdoor heat exchanger 5 begins to form frost. When frost starts, the outdoor heat exchanger temperature sensor 6 determines the frosted state, and when a predetermined temperature and a predetermined time are reached, the four-way valve 2 is switched to perform a defrosting operation for removing frost from the outdoor heat exchanger 5.

[0004]

However, in the above method, when the outdoor heat exchanger temperature sensor 6 has a migration phenomenon or a sensor failure such as a sensor mounting failure, the defrosting operation cannot be performed and the heating capacity is deteriorated. In addition to making the user uncomfortable, when the frost grows, the outdoor fan is locked and the fan cracks, and when the frost grows to the charging part of the electrical component, a dead short occurs, which causes a problem in safety.

The present invention has been made in order to solve the above problems, and an object thereof is to provide an abnormality judging device for an air conditioner which judges abnormal frost formation.

[0006]

In order to solve the above problems, the present invention compares and calculates a temperature detected by an indoor heat exchanger temperature sensor of an air conditioner and a predetermined temperature. Means for measuring the temperature of the indoor heat exchanger temperature sensor when the temperature of the indoor heat exchanger is lower than or equal to a predetermined temperature, time measuring means for performing a time calculation and comparing with a predetermined time, and when the time measuring means reaches a predetermined time. It is equipped with an emergency stop means for notifying the contents of the abnormality by turning on the abnormality display while stopping the compressor.

[0007]

According to the present invention, with the above structure, the temperature detected by the indoor heat exchanger temperature sensor is compared and calculated, and the time is measured from the time when it is determined that the temperature is lower than the predetermined temperature. Is to stop.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An abnormality determination device for an air conditioner according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a refrigeration cycle diagram of the air conditioner of the present invention. The same parts as those in the conventional example are designated by the same reference numerals and the description thereof will be omitted. FIG. 2 is a time chart of the indoor heat exchanger temperature sensor when the outdoor heat exchanger temperature sensor is normal, and FIG. 3 is an indoor heat exchanger temperature sensor when the outdoor heat exchanger temperature sensor is in the defrosting operation inoperative state. Is a time chart of.

The controller 8 compares the indoor pipe temperature Ta detected by the indoor heat exchanger temperature sensor 7 of the air conditioner with a predetermined temperature Tb, and a comparison operation means for comparing the indoor heat. Exchanger temperature sensor 7
When the temperature is determined to be equal to or lower than the predetermined temperature Tb, the time is measured, and the time measurement means compares and calculates with a predetermined time Hm. When the time measurement means reaches the predetermined time Hm, the compressor 1 is stopped and an abnormality occurs. It is equipped with an emergency stop means that lights up the display and notifies the user of the details of the abnormality.
Reference numeral 9 is an abnormality indicator lamp for displaying abnormal frost formation.

The controller 8 is set with a predetermined temperature Tb for comparison calculation with the indoor pipe temperature Ta measured by the indoor heat exchanger temperature sensor 7 in advance, and a predetermined calculation for comparison calculation of how much the predetermined temperature Tb has elapsed. Time Hm
To set. The predetermined time Hm is longer than the rising time Hb from the start of the heating operation until the temperature reaches the predetermined temperature Tb, and the predetermined temperature Tb after the defrosting is completed after the defrosting is started and falls below the predetermined temperature Tb. It is set to be longer than the time Hc until it exceeds.

When the outdoor heat exchanger temperature sensor 6 of the air conditioner is operating normally during the heating operation in which the outdoor air temperature is low, the evaporation temperature of the outdoor heat exchanger 5 decreases as in the conventional example. Even if frost starts on the outdoor heat exchanger 5, the outdoor heat exchanger temperature sensor 6 determines the frosted state, and when the predetermined temperature and the predetermined time are reached, the four-way valve 2 is switched to the outdoor heat exchanger 5
Perform defrosting operation to remove the frost. The time chart of the indoor heat exchanger temperature sensor when the outdoor heat exchanger temperature sensor 6 operates normally and the defrosting operation is occurring is as shown in FIG. 2, and the indoor piping temperature Ta is determined in advance. The temperature lower than the predetermined temperature Tb does not become longer than the time Hc. When the outdoor heat exchanger temperature sensor 6 causes a migration phenomenon or a sensor failure and frost starts on the outdoor heat exchanger 5, the temperature of the indoor heat exchanger temperature sensor 7 gradually decreases even if the compressor 1 is operating. come.

Next, the operation of the abnormality judging device for the air conditioner in the embodiment of the present invention will be explained based on the flowchart of FIG. When the heating operation is started, the indoor heat exchanger temperature sensor 7 detects the indoor piping temperature Ta, and the detected temperature T
A and the predetermined temperature Tb are compared and calculated (step 1). Then, if the detected temperature Ta is equal to or lower than the predetermined temperature Tb,
Next, the time is measured, and the measured time Ha and the predetermined time Hm are compared and calculated (step 2). The long time after the indoor piping temperature Ta has dropped below the predetermined temperature Tb indicates that the outdoor heat exchanger temperature sensor 6 is defective. Therefore, when the predetermined time Hm is reached, the compressor 1 is stopped (step 3), and the abnormality display is lit on the abnormality display lamp 9 to notify the details of the abnormality (step 4).

[0014]

The abnormality determination device for the air conditioner of the present invention is
With the above configuration, it is possible to prevent the deterioration of the heating capacity and the cracking of the outdoor fan that occur when the temperature sensor of the outdoor heat exchanger is abnormal, and to prevent the growth of frost on the electrical components and improve the safety.

[Brief description of drawings]

FIG. 1 is a refrigeration cycle diagram of an air conditioner of the present invention.

FIG. 2 is a time chart showing the contents of normal operation of the air conditioner.

FIG. 3 is a time chart showing an abnormal operation due to frost formation in the air conditioner.

FIG. 4 is a flowchart of an abnormality determination control device of the present invention.

FIG. 5 is a conventional refrigeration cycle diagram.

[Explanation of symbols]

 1 Compressor 2 Four-way valve 3 Indoor heat exchanger 4 Expansion valve 5 Outdoor heat exchanger 6 Outdoor heat exchanger temperature sensor 7 Indoor heat exchanger temperature sensor 8 Controller 9 Abnormality indicator lamp Ta Indoor piping temperature Tb Specified temperature Hm Specified time

Claims (1)

[Claims] 1. A comparison calculation unit for comparing and calculating a temperature detected by an indoor heat exchanger temperature sensor of an air conditioner and a predetermined temperature, and the comparison calculation unit sets a temperature of the indoor heat exchanger temperature sensor to a predetermined value. When it is determined that the temperature is lower than the temperature, the time is measured, and the time measurement means compares and calculates with a predetermined time. When the time measurement means reaches the predetermined time, the compressor is stopped and the abnormality display is lit to notify the content of the abnormality. An abnormality determination device for an air conditioner, which is provided with an emergency stop means.