Home » Cars » Why Is My Car Aircon Not Cold

Why Is My Car Aircon Not Cold

By Kathleen Burgess


Published on

Thanks to the invention of air conditioners for automobiles, car owners remain comfortable while driving even in hot days. However, ACs have the tendency to malfunction, too. Luckily for you, we have all the answers in case you ask yourself: “Why is my car aircon not cold?”

The Causes

There are six common problems associated with a malfunctioning car AC. Pay attention to the following issues:

The AC system leaks freon

According to AutoAid, freon is a specific type of refrigerant that can make warm air cool for cars. If the AC system loses a significant amount of this chemical liquid, it goes without saying that nothing will change the temperature of warm air anymore.

The causes of freon leak are:

  • broken hose
  • detached gasket
  • detached connection

However, you can only determine the cause by removing the AC from its location. Here’s what you should do:

  1. Prepare a screwdriver, water hose, spray nozzle, and sealant.
  2. After removing the AC, put it on a hard surface like concrete or wood.
  3. Take off the AC’s cover with a screwdriver.
  4. Connect the water hose and the spray nozzle to completely remove dirt, grime, and debris from the AC.
  5. Take off the filters to find the compressor.
  6. Inspect the compressor’s area to locate the leak.
  7. Apply the sealant on the leak’s specific location while following the product’s instructions.
  8. Reinstall the cover before putting the AC back in place.
  9. Turn on the AC to know if you have solved the problem.

If the AC is still acting up, do the whole thing again. If it’s still not working, hire a professional technician.

The amount of freon is low

Leakage is not the only reason why AC systems run short on freon. Sometimes, it’s all about constant use over the years.

And, that’s okay!

All you have to do is recharge the AC. Remember the following steps if the cause is not leakage:

  1. Prepare the right kind of AC dispenser, meat thermometer, refrigerant (take note of the car’s required amount), safety glasses, and safety gloves.
  2. Find the low side pressure port that has an “L” symbol on top, which is usually on the engine bay’s passenger side.
  3. Securely connect the recharge hose to the port by waiting for that audible click.
  4. Start your car and activate the AC to its maximum settings.
  5. Observe the pressure gauge to ensure that the AC is indeed undercharged (under 40 psi).
  6. Connect the refrigerant can and the recharge hose.
  7. Hold the can in an upright position.
  8. Add refrigerant by squeezing the trigger up to 10 seconds or until the gauge shows 40 psi.
  9. Insert the meat thermometer into the AC vents near the steering wheel.
  10. Check the thermometer if it shows 28 degrees.

Don’t fix this problem on your own if you spot more than 40 psi on the gauge the first time you see it. That’s a serious issue that needs professional repair.

The blend air door is jammed

The first two issues are complicated, don’t you think? Good thing that the next one is easy enough.

What exactly is the purpose of the blend air door? Simple: it closes the ventilation system to block warm air.

To fix this problem, just reach out and adjust the blend air door. The only challenge is its location. It is found deep behind the dashboard.

The compressor is not working

Just as the name suggests, the compressor’s responsibility is to compress freon to allow maximum expansion later on for a much colder temperature.

Check out the process behind compressor repair in a nutshell.

  1. Drain the system to completely remove refrigerant.
  2. Take off the compressor.
  3. After ensuring that the whole AC system has no debris, leaks, and other problems, attach the new compressor.
  4. Install a new throttle valve and O-rings.
  5. Refill the system with fresh refrigerant.

The condenser is clogged or damaged

To minimize refilling the AC system with freon regularly, there’s a condenser that converts refrigerant gases to liquid all over again. Unfortunately, when it is blocked by impurities or has a broken form, freon liquid can’t flow through.

To be honest, replacing the damaged condenser with a new one is quite complicated. It is best to let the pros handle it.

There are electrical problems in the AC system

A common electrical problem happening inside ACs is a damaged fuse. This is easy enough for DIY pros when it comes to electrical issues.

However, for other types of electrical repairs in your car, there are safety risks. Stop being a hero and let a certified mechanic fix it.

How to Maintain Car Aircon

To avoid dealing with a broken AC, try your best to take good care of it even if it’s still working perfectly. Don’t worry; car AC maintenance is pretty easy. Check these out!

Turn on the AC even if it’s already too cold

Common mistakes of car owners usually happen during the winter season. One of which is not using the AC for several weeks just because it’s unnecessary.

Based on the maintenance tips from Medlock Gulf, it’s important to let the AC run for at least 10 minutes every week. For best results, adjust it to its highest settings. You should also activate the defrost for at least five minutes weekly.

What happens when you do this?

You’ll be able to maintain the compressor and the gas pressure as well. Both of them are essential for the AC system.

Let the pros handle your car every two years

You know what they say in the medical world, a second opinion is valuable. The same idea goes for cars. So, even if you’re a good DIY technician or mechanic, you should allow the professionals to inspect your entire automobile from time to time.

Of course, that includes the AC system.

A two-year interval is not that bad for your budget and time. That’s just a small price to pay for the best version of your car.

Clean the filter

Maintaining the car AC filter is not rocket science. Just take it off from the glove box and shake it to remove dust, grime, and debris. You may also wash it with soapy water.

Also, don’t hesitate to replace the filter if it’s already worn out.

Inspect the grills near the windshield

What does this have to do with car AC maintenance?

It turns out that the exterior grills can catch leaves and other larger debris. That leads to the possibility of an AC system sucking every object entering the grills.

Speaking of debris, you may also clean the condenser with a hose. You should open the hood first.

In Conclusion

When you ask yourself “why is my car aircon not cold,” remember to check for leaks, the freon quantity, blend air door, compressor, condenser, and electrical wires. Despite every repair method we’ve discussed, we still think that you should hire a professional to do it. Freon is a toxic liquid that requires careful handling.

What’s even more important than cool air is the quality itself. To improve air quality in your car, learn how often to change cabin air filters. You should also buy a high-quality air freshener.

About Kathleen Burgess

Kathleen started her career in journalism writing about cars during her Journalism degree at CUNY and even though she didn't like it at first, she quickly became an ace, writing news, reviews and comparisons like one of the best car writers out there. Today she writes content focusing on the latest trends in the car industry, looking at sales, policies and green alternatives. Learn more about GCB's Editorial Process.

Leave a Comment