A/C Pro

When You Shouldn’t Use A/C Pro

In most cases, if your car air conditioner is blowing warm air, A/C Pro is the fast, easy way to fix it yourself and save money.

However, there are situations where you’ll probably need to take your car to a professional mechanic instead. A/C Pro won’t fix a broken compressor clutch, for instance, or replace a bad condenser coil.

So how do you know whether you need to go to a mechanic or use something other than A/C Pro? Below is a list of the situations in which you should not use A/C Pro.

Don’t use A/C Pro if:

Your car was built before 1994 and has never been converted from R-12 to R-134a.


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This one’s going to be rare if the car’s been driven much, because if the A/C has broken down at any point in the past 20 years, it would have likely been converted to R-134a in the process of getting it fixed. However, if you do have an old R-12 system, you can’t use A/C Pro until it’s been converted to R-134a. (All cars built since 1994 will have R-134a systems, which is what A/C Pro is designed for.)

You drive a hybrid or electric car.


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This is because most hybrid cars (and all electric vehicles) use an electric A/C compressor, which requires a different type of compressor oil. A/C Pro contains compressor oil, but it’s the type used in regular belt-driven A/C systems.

It took less than two weeks for your A/C to go from cold to hot.


A/C Pro seals small leaks in rubber A/C components, such as o-rings, gaskets, and hoses, which are what usually causes a system to become low on refrigerant. A leak is considered “small” if it takes at least two weeks for the refrigerant to leak out. If your A/C was cold yesterday and today it’s blowing hot air, you have a problem bigger than A/C Pro can fix.

Your compressor is running, but the A/C pressure is too high.


Before adding A/C Pro, one of the first steps is to use the A/C Pro gauge (which can also be bought separately) to check the system pressure. The gauge measures the low-pressure (or suction) side of the A/C system. When the compressor is running, it should create suction and lower the pressure reading. (When the compressor is not running, it’s normal for the gauge to show a high reading.)

If the pressure is too low due to a lack of refrigerant, adding A/C Pro will bring it up to the correct range. However, if the compressor is running and the pressure is too high, that either means that the system has too much refrigerant or that there is a problem with the compressor. Keep in mind that the belt will be constantly moving, even when the compressor is cycled off. To be sure the compressor is running, watch the center pulley.

You’ve already added A/C Pro. 


Here’s the scenario: you recharge your system with A/C Pro and it works, making your air conditioner ice-cold. However, after a few weeks or months, the air from the A/C starts to get warm again. This indicates that you have a slow leak in a metal A/C component, since A/C Pro will have sealed any small leaks in the rubber components (which are more common). At this point, before adding any more refrigerant, you’ll need to seal the metal leak—which you can do using Super Seal.

If one of those five conditions apply, A/C Pro is currently not for you. However, if your car’s air conditioner is blowing hot air because it’s low on R-134a refrigerant, and it’s taken at least two weeks to get that way, A/C Pro can fix your problem and save you time and money.

If you have any questions, please contact us.