Main Reasons Causing The AC System Not Working

It is not very uncommon to see faults with your car’s HVAC system, especially when it is old cars we’re talking about. It is not rocket science to learn about reasons car AC not working. The reasons are pretty simple and understandable, and sometimes, you can even fix them at home. However, even if you cannot fix it yourself, learning about the reasons, can at least make you more aware of the symptoms. This, in turn, makes you more prepared.

Usually, when your car’s cooling or heating breaks down, it is accompanied by weird sounds or smells. However, it is not always that any conspicuous symptoms may manifest themselves. This is why, it is important to know the reasons for HVAC failure, so you can take due care of it.

Common Damages That Show Reasons Car AC Not Working

1. Air conditioning shows the wind, not the cold

If the heating not working in car, the first cause is must be a lack of gas. In the system, the gas is compressed into the compressor and then transferred to the liquid in the outdoor unit. As the pressure drops dramatically, the throttle valve moves to the gas. When it is moved to the cooler, it is taken to the ambient temperature and there will be cold air blowing out from the fan. If the gas is not enough then the machine will only wind, not cold or very weak.

Reasons car AC not working
Reasons car AC not working: Show the wind, not the cold

In addition, the cause may arise from the air conditioning filter. When used for a long time, dust and dirt on the screen are unavoidable. The filter is dirty so the wind can’t enter the cab but only in the indoor unit.

2. AC closed continuously

The car’s on / off switch is controlled by sensors and switches. At this point, the gas pressure in the system is higher than the manufacturer’s recommended level is the main cause. When the system automatically detects abnormal pressure, the system will disengage the throttle clutch to protect other parts of the system.

To be limit the reasons car AC not working, users will not be able to process the device without a dedicated device. To find the right cause and the most effective way to overcome the above phenomenon, take your car to a reputable service center for advice and repair.

3. Cooling system in automotive air conditioning system

Many drivers argue that cold sticking in the pipes surrounding the condenser is a good sign that the air conditioning system is working well. However, that is the most basic mistake that leads to many unfortunate failures.

However, when the air conditioning system is seriously deficient in cold gas, the pressure in the reservoir drops sharply, leading to a marked decrease in the boiling point of the gas. Refrigeration will evaporate at a lower temperature, causing the temperature of the array to be much lower than the condensation temperature of the water. From there, the water vapor in the air blows from the stretcher to freeze on the surface of the tube and the openings, the sheath of the rig.

4. The air conditioning system works normally but not cool or very weak

At this time two situations occur. First of all, with the new car, most of these cases are due to the air conditioning filter being blocked. In the process of using the vehicle, depending on terrain conditions, the dirt gradually sticks to the screen, too much will thicken the wind in the indoor unit without access to the car cabin. The solution is to clean the screen mesh.

Reasons car AC not working
Reasons car AC not working: Works normally but not cool or very weak (Photo: Brand X Pictures)

For vehicles that have been used for many years, the cause can be more complicated than that. Caused by the rope crab-roa cold air coincide and slip. Or the system may be damaged due to aging pipes, leaks, or openings. The car should be brought to professional repair centers to be processed by specialized machinery.

5. The air conditioning system works normally but has an unpleasant odor

This is probably the highest percentage of car owners who have problems with car air conditioners and this is one of some reasons car AC not working. The causes of this condition include both subjective and subjective. The objective reason is that the ventilation system cooled into the cab (including the cooler, air filter, fan, air outlet and temperature sensor) was dirty or malfunctioning.

Reasons car AC not working
Reasons car AC not working: Works normally but has an unpleasant odor (Photo:

Caused by the car to long-term passenger dust with impurities such as sweat, garbage, cigarette smell, fragrance, food smell … in the corners of the car interior. When the air conditioner is running and the wind blows into the cabin, the impurities will rise.

Top 5 Reasons Car AC Not Working

There could be many reasons for it, but here are the top 5 reasons why all the heating or cooling systems of your car may go out of tune. Whether it’s manual cars or automatic, these 5 are most often the culprit.

Leakage from seals or hoses

Coolants and refrigerants that are present in the heating/cooling systems within sealed hoses are prone to leakage due to lack of maintenance. This is the most common cause of such failure. Though it is difficult to find leakage without taking a full view from beneath the car, you can check it during regular servicing. Checking your gas charge is also a good time for such a diagnosis.

Maintenance Tip: Ask your service provider to check for such leaks during your scheduled car service. And, don’t skip it because there is a score of good reasons why you should not skip car service.

Fault in thermostat

There’s a very thin chance that your car came with a manufacturing fault in the thermostat. The usual reason for such a fault is fluctuating cabin temperatures. In case your car is fitted with a manual cooling/heating control, there could be a problem with the switch, compressor clutch, sensor, or even pressure cut-out.

Read more:

Fault in compressor

Reasons car AC not working
How to avoid AC Not Working problems in your car (Photo: ChrisFix/Youtube)

This reason is rather conspicuous. In case you hear loud, weird noises while you switch the AC on, it indicates a faulty AC compressor. Besides, it could also indicate a problem with the pressure of the refrigerant. Also, chances are that you have been using the wrong kind of compressor lubricant. Make sure that the noise isn’t issuing from the engine. Make sure that the noise isn’t coming from the engine. Else, it’s not a compressor issue. In either case, get it checked ASAP.

Electronic fault

Automatic cars and manual cars with advanced electronic features most often suffer from this problem. The more complex your car, the higher the chances for electronic faults. When more electronic features are added to your cooling/heating system, it increases the chances of things going out of order. It may increase the ease of use and comfort, but it also increases the scope of repairs. Electronic faults could be one of the major reasons why heating or AC stop working.

Presence of bacteria

Reasons car AC not working
Too many bacteria build-up is one of the reasons car AC not working (Photo:

Loss of cooling or heat could also be because of bacteria buildup. There is a possibility that mold, bacteria, or mildew may have accumulated on the evaporator coils. The clear symptom if this problem is a weird smell in the cabin.

It is important to cater to the problems right when you start noticing the minutest of the symptoms. In cases where no symptoms are manifest, it can be a bummer. To avoid this, make sure that you do the suggested checks at the time of service.

Watch the video to learn how to fix a faulty car AC by yourself:

Tips to Check Your AC While It Doesn’t Work

1. Check the gas pipe temperature

If there are abnormal signs you can check quickly by touching the gas pipe, finding warm in the high-pressure line, and cool in the low-pressure line is okay. Manufacturers of high-pressure tubes have a smaller diameter than low-pressure tubes. If the temperature between the two tubes does not differ much, then your air conditioning may be a problem.

2. Check the compressed air system

The second one is due to the crankshaft connecting the engine to the compressed air, resulting in loss of power and the compressor can’t compress the refrigerant to the required pressure. You can open the bonnet and check the compressed air system. The end of this system is cues, we can see whether it runs at a higher speed or slower than normal, this section requires you to check regularly to be able to recognize the difference.

Reasons car AC not working
Re-check the air-compressed system if you have any problems with the car AC (Photo: Getty Images)

3. Check the wind speed of the AC

Besides, there are also reasons such as the cold soiled dirt that causes the wind to be blocked, and the heat dissipation around, resulting in a reduced cooling effect. You can check whether the wind speed is strong or weak. If the high-voltage and low-pressure wires are normal, it may be necessary to clean the chillers. To measure the cooling effect, keep the engine at 1,500 rpm, and air conditioning at the highest level. After 5 minutes, you can measure the temperature of the cabin and the temperature of the wind blowing out of the cooler. If the temperature is high, you should check the entire air conditioning system.

So there is full information you may want to know while having problems with your car’s air conditioner. And It also answers all of you about reasons car AC not working. If you like this kind of information about car maintenance, follow us for more daily updated articles to satisfy your demands.