Is there overheating protection for automotive air conditioners?

Overheating protection is present, normal.

The temperature protection and compressor overheating protection of automobile air conditioner are both to protect the refrigeration circulation system of the air conditioner so that it can work normally.

The two types of protection are as follows:

1) Temperature protection of the air conditionerIn order to prevent frost on the surface of the evaporator, the air conditioning control system uses an evaporator temperature sensor with negative temperature characteristics to detect the surface temperature of the evaporator. When the temperature of the evaporator is lower than 2, the air conditioning control system will automatically cut off the compressor, and when the temperature of the evaporator is higher than 5, the compressor will be automatically started.

2) Compressor overheating protection When the temperature of the compressor housing is abnormally high, such as at 150, the thermal protection switch on the compressor is disconnected, so that the compressor stops working. When the temperature of the compressor casing drops to 130, the thermal protection switch closes and the compressor starts working again.

Introduction to Automotive Air Conditioning:

Automotive air conditioning device (air conditioning device) is referred to as automobile air conditioner. It is used to adjust and control the temperature, humidity, air cleanliness and air flow in the car compartment in the best state, provide a comfortable riding environment for the occupants, and reduce the fatigue of the journey; Ventilation devices that create good working conditions for drivers and play an important role in ensuring safe driving.

It generally includes refrigeration units, heating units and ventilation units. This kind of combined device makes full use of the limited space inside the car, has a simple structure and is easy to operate, and is an internationally popular modern automobile air conditioning system.

Not air conditioner overheating protection. Abnormal.

The air conditioning pump of the automobile air conditioner is driven by the engine, not directly driven by the motor, so the air conditioning pump itself does not have the problem of overheating protection.

However, it is definitely abnormal that the car air conditioner can be used normally in the morning, but it cannot operate normally in the afternoon. And most of them are caused by the abnormality of the air conditioning system, such as high pressure protection, exhaust temperature protection and so on.

It is recommended to go to a local regular maintenance shop for maintenance personnel to check and confirm the operation of the entire refrigeration system, and if necessary, the refrigerant in the system pipeline should be completely replaced.

There is no automatic protection, either there is no oil, or it is aging.

The overheating protection of the air conditioning compressor is because the air conditioning compression pump will encounter a variety of protection measures imposed by the inevitable harsh conditions under working conditions. Typical states that will be encountered in the work of air conditioning (refrigerator freezer) compression pump are: 1. There is a large deviation from the rated working voltage; This causes the overload heating of the compression motor of the air conditioner.

2. The air conditioning compression pump is shut down and restarted for a short time; Because the high-pressure end of the refrigerant in the zhidao pipeline has not been fully released, the compressor motor is energized and under heavy load, resulting in the motor being overstressed and unable to spin normally. 3. Refrigerant leakage in the air-conditioning compressor; As a result, the heat generated by the idling of the compression pump motor cannot be diffused on the diffuser of the air conditioner through the refrigerant flowing out during normal operation. from the heat generated by the compression pump of the air conditioner.

4. Aging of air conditioning compression pump: aging of air conditioning compression pump for a long time, power decline, internal friction resistance rise, and other factors. It causes the heat generation of the compressor pump of the air conditioner to increase.

In view of the above reasons, the design of the traditional air conditioning compression pump adopts the following answer: in the air conditioning compression pump circuit, a bimetal sheet is installed on the pump body to disconnect the power supply by heating deformation, and the bimetal sheet automatically returns to the position after the temperature returns to normal. Such a simple and practical device for the purpose of overheating and overcurrent power-off protection of the compression pump - "thermal protector". Figures.

As you described, a different thermal protector of the same model should solve the problem. Fig; Typical air conditioner thermal protector.

There are generally several situations of air conditioner overheating protection, and there are different categories according to the size of the air conditioner, mainly in several aspects:

1. Built-in protector for air conditioning electrical parts. Mainly supply air motors and compressors. The compressor is generally built on top and is recoverable. When the temperature is too high, it will be disconnected, and the temperature will be restored after normal.

2. There are generally several kinds of protection on air conditioning control

1) Current protection, if there is a detection press current on the air conditioning control board, it will be protected if it exceeds the set value.

2) Pressure protection, many air conditioners have high and low pressure switches, which are protected by more than the protection value.

3) Overheating protection, the air conditioner is generally equipped with a temperature sensor to protect the compressor, and generally detect the exhaust temperature of the compressor or the top temperature of the compressor. Exceeds protection value protection.

There are many situations that cause overheating protection, mainly divided into normal and abnormal, normal is when the air conditioner works in very harsh conditions, such as very high ambient temperature refrigeration, press load too much protection. The abnormality is mainly due to the problem of the system, such as the lack of freon, the pipeline is blocked, the fan does not rotate, etc., which should be judged according to the specific situation.

1. The filter screen of the internal unit and the condenser of the external unit are too dirty.

2. The system pressure is too high (the pressure under normal conditions is fine, and if it is too high, put some fluorine).

3. If there is a deflated connecting pipe, it is recommended to check the connecting pipe, and if the deflated pipe is too serious, replace it.

4. The compressor itself is faulty, so the compressor can only be replaced.

5. If it is more than 5p, you should also consider the pressure protector.

I opened the top cover of the outer unit and flushed the compressor. Fix the problem temporarily.

The built-in protectors of the electrical parts of the air conditioner are mainly the air supply motor and compressor. The compressor is generally built on top and is recoverable. When the temperature is too high, it will be disconnected, and the temperature will be restored after normal.

The main thing to solve this is to see if the fan is rotating, if the fan is rotating, then there is too much dust in the heat sink of the external machine, blocking the air outlet, as long as the dust on the heat sink is cleaned.

Solutions for compressor overheating protection: 1. The heat sink of the outdoor unit is too dirty, and the heat sink is cleaned;

2. When the fan speed drops, rinse the radiator of the outdoor unit with a tap water pipe;

3. The filter screen of the indoor unit is too dirty, clean it in time;

4. If there are too many freons, find a professional maintenance personnel to check the pressure measurement, then vacuum, and then add fluoride after fluoride.

Causes and solutions for thermal protection of air conditioners:

1.Poor heat dissipation due to environmental factors of the outdoor unit. Solution: Relocate the machine.

2.The outdoor unit is facing the wrong direction and has been exposed to sunlight for a long time. Solution: Reinstall it in a suitable place or add an awning.

3.The outdoor condenser is too dusty and dirty. Solution: Clean the condenser with a special air conditioner fin cleaner.

4.Poor heat dissipation of the outdoor unit, damage to the fan that does not rotate or slow speed, insufficient capacity of the fan capacitor or damage. Solution: Replace the fan and capacitor.

5.The compressor starting capacitor is invalid or the capacity is insufficient, and the compressor starts fails. Solution: Replace the compressor starting capacitor.

6.Compressor overheat protection device is damaged. Solution: Replace the compressor overheat protector.

7.Problems with the compressor itself, jamming, coil burnout, etc. Solution: Replace the compressor.

8.Refrigerant problems, too much or too much or too little compressor overheating protection during long periods of operation. Solution: Check the pressure value of the refrigerant and control it to the normal range.

9.System blockage, ice blockage, dirty blockage, etc. Solution: Clean the refrigeration system and vacuum to replace the refrigerant.

The overheat switch protection of the air conditioner should be in a normally open state, and the main dust roller should be fully lubricated by the compressor.

Automobile air conditioning units have become one of the indicators to measure whether the car is fully functional. Generally comprises refrigeration device, heating device and ventilation device, this combined device makes full use of the limited space inside the car, the structure is simple, easy to operate, is the internationally popular modern automobile air conditioning system.

Car Air Conditioning Function:

1.The air conditioner controls the air temperature in the cabin, heating and cooling the air to a comfortable level.

2.Air conditioners are capable of expelling moisture from the air. Dry air absorbs human sweat to create a more comfortable environment.

3.The air conditioner can draw in fresh air and has a ventilation function.

4.Air conditioners filter the air and remove dust and pollen from the air. (Photo by Xu Shuanghe) @2019

Overheating protection is due to the aging of the compressor, the reason for low voltage, and the reason for serious dust in the external unit. What you can do is to thoroughly clean the dust of the external machine, and buy a special detergent to spray the evaporator of the external machine, and the effect is very good.

Be careful with short circuits in watering.

The front cover is not safe without cover, and it has little impact on heat dissipation.

Is there any harm to not covering the air conditioner when it is on? Written with rewards.

Is there any harm to not covering the air conditioner when it is on?

When the family turns on the air conditioner, they keep the lid open, that is, the lid that opens the lid and takes the filter, and says that it is more powerful, is it really useful, and why do I feel that it is a confusing behavior in the world.

Write a reward for a total of 1 crack leak.

Quite a little trick.

From a theoretical point of view, if the return air panel of the indoor unit is not covered during the use of the household split wall-mounted air conditioner, it can reduce the circulating wind resistance of the indoor unit to a certain extent, that is, the refrigeration capacity of the air conditioning unit can be increased.

However, this search is only theoretical.

If you want to achieve this purpose, you can cover the return air panel of the indoor unit, and pull out the return air filter directly, so that the circulating air volume can become larger and the cooling capacity will be larger.

This unconventional method of use is not normally recommended.

Some auto-no-air overheat protection switches are located on the cylinder head of the compressor and some at the outlet of the evaporator. Its purpose is to protect the air-conditioning refrigeration circulation system and make it work properly.

The temperature protection of the empty car and the overheating protection of the compressor are both to protect the empty refrigeration circulation system so that it can work properly. The two types of protection are as follows: (1) Air temperature protection In order to prevent frost on the surface of the evaporator, the air control system uses an evaporator temperature sensor with negative temperature characteristics to detect the surface temperature of the evaporator.

When the evaporator temperature is lower than 2, the air control system will automatically cut off the compressor, and when the evaporator temperature is higher than 5, the compressor will be automatically started. (2) Compressor overheating protectionWhen the temperature of the compressor shell is abnormally high, such as 150, the thermal protection switch on the compressor is turned off, so that the compressor stops working. When the temperature of the compressor casing drops to 130, the thermal protection switch is closed, and the compressor starts working again.

The overheating switch mounted on the cylinder head of the compressor is a temperature-pressure excitation induction switch. Normally, this switch is in the off position. When the system is in a state of high temperature and high pressure or low temperature and low pressure, the switch remains normally open; This switch closes when the system is in a state of high temperature and low pressure.

When the refrigerant is lacking, it is common for the system to finish at high temperature and low pressure. At this point, if the compressor continues to operate, it will be damaged due to lack of lubrication and overheating. The overheat switch stops the compressor from spinning until the fault is eliminated and then resumes operation, acting as an automatic fail-safe operation.

In the case of Nissan, the overheating switch of its air regulator is placed on the outlet pipe of the evaporator. When the temperature of the refrigerant rises to a certain value, the evaporation pressure under the diaphragm makes the diaphragm rise, and the screw drives the moving contact to contact the fixed contact, and the overheating switch is turned on, and the overheating time relay is connected in series behind the overheating switch. When the overheating condition is persistent rather than instantaneous, the leak warning light is illuminated.

Millions of car purchase subsidies.