It is absolutely fine for your car when its AC compressor cycles to keep a check on the internal pressure. However, if your AC compressor is indeed cycling on and off rapidly, that is something you should be worried about. People usually keep their car AC systems at an idle state in winter months, not knowing how harmful it can be to the car AC health.
The main causes behind your car AC compressor running non-stop are low refrigerant level, leaking refrigerant, or a dirty condenser. A point to note is that all these conditions can arise when you don’t use your car AC for a long time.
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Top 3 Reasons Why Your Car’s AC Compressor Cycles On And Off At Idle (With Solutions)
Your AC compressor cycling on and off simply indicates that the AC unit is working fine to cool your car’s temperature. Normally, it should cycle around 2 to 3 times per hour, but you can expect a higher running time if the temperature is hotter than usual.
If the AC compressor is going on and off non-stop, that should be a concern to you. Your car AC compressor short cycling non-stop can overwork the AC system and can escalate to more serious issues.
Here are the top 3 reasons why a car AC compressor can cycle on and off non-stop while idling along with ways to fix the issue:
#1 Not Enough Refrigerant (Freon)
Some of the refrigerant can be lost over time due to your car compressor AC being idle or due to some leaks. This can cause the pressure to drop when the AC compressor gets engaged. Now, triggering the low pressure can turn off the compressor. The pressure will stabilize in one or two seconds and the compressor will get engaged once again and the cycle repeats. This is called the low-pressure cutout.
The reverse of this situation is called high-pressure cutout which can be caused due to too much refrigerant in your system. That too can lead to your car AC compressor rapidly cycling on and off at idle.
A lack of refrigerant indicates that less oil is circulating through your AC system. It will be harder for your car AC to cool down the car’s temperature. This can even lead to a catastrophic compressor failure which would require you to replace the entire system. Fortunately, that is not the case here!
Keeping your car idle for long durations at a stretch can lead to a lot of refrigerant loss. This happens quite frequently in times of winter when you probably wouldn’t be using your AC much.
Solution: This is also called a low charge problem and the best thing about this is that your compressor isn’t broken. It is pretty common and the good news is that you can fix it yourself. There are a couple of steps that you need to follow to fix this condition:
- Check for and repair leaks (if any) that could result in loss of refrigerant.
- Check the pressure to confirm that low refrigerant is the problem
- Test the AC system
- Add refrigerant
Once your car AC system is properly charged, the issue will be solved. Here’s a YouTube tutorial to help you recharge your car AC:
Note: You will need to buy an AC recharge kit to refill refrigerant into your car AC system.
Another thing to take away from here is that keeping your car AC system idle for too long isn’t a good idea. As a precautionary measure, you should keep the car AC on for at least 30 mins per week. This will trigger fluid supply through the AC system and keep all the AC parts active and in good health.
#2 Condenser is Extremely Dirty
Condensers are bound to get dirty with regular usage. However, if your condenser is way too dirty, it can prevent the refrigerant from cooling. Even the subcooled liquid will come out at a higher temperature. This triggers the high-pressure cutout to prevent any further damage to your compressor. Hence, the pressure cutout leads to your compressor cycling on and off at idle.
To summarize, when the condenser coils (especially the evaporator coil) are too dirty with dirt, debris, and dust, the compressor can cycle on and off too quickly. The reason behind it is that now the drying process gets delayed and your AC compressor has to work harder to cool down your car. This issue can happen anytime although keeping your car AC system idle can escalate the situation.
Solution: All you need to do to get rid of this problem is clean your car AC’s condenser coils, especially the No products found.. Here’s a video tutorial to help you out:
To avoid this problem from now on, make it a habit to clean your car condenser periodically.
#3 Auto Climate Setting
If you have the auto-climate setting turned on, that too could cause your compressor to keep cycling on and off. Regardless of whichever season you are in, be it summer or winter, the AC compressor will keep running non-stop.
Solution: Do check if your car’s auto-climate feature is on. If not, then the aforementioned factors could be the cause.
Final Words
We hope you now have understood why your car AC compressor can run non-stop. As mentioned in the above points, you shouldn’t keep your car AC system idle for a lengthy period. Use it frequently even in the winter months to ensure keeping it in a healthy state. Otherwise, the car AC system might become faulty, and replacing it can be quite expensive. We are not asking you to keep your car AC running all day long in the winter. Turn it on for at least 30 minutes every week and you are good to go. Another point to remember is do clean your car’s AC system, including all its parts, regularly.