Updated at: 08-07-2022 - By: Lucas

Has the cool air from your AC stopped coming out? If so, the freon might need to be checked and refilled.

How do you know? Also, how do you check the level of freon and, if necessary, recharge the AC?

A freon gauge can be used to check how much freon is in a car. Under normal conditions, the gauge should read between 25 and 45 psi. If the freon level is below this range, it’s likely that the freon needs to be refilled.

Here are the most common signs that your freon level is low that you should look out for.

Signs That Your Freon May Be Low

How To Check Freon Levels In Car

If your car needs more freon, there are a few signs that will let you know. Here are some of the most common signs:

1. The AC Isn’t as Cold as It Once Was

You may still feel cold air coming out of the vents, but if it’s not as cold as it used to be, freon may have leaked out of the unit.

2. The AC Doesn’t Produce Any Cold Air

If your car doesn’t make any cold air, that means all the freon has leaked out. This could happen all at once or over a period of time.

3. You Cannot Hear the AC Clutch When the Unit Is Turned On

When you turn on your air conditioner, if you hear a clicking sound, that means it is working correctly. If you don’t hear this sound anymore, it could mean that your unit is out of freon.

If there isn’t enough freon in the unit, the clutch won’t work. By adding more freon, the AC clutch will work again.

4. Visible Freon Leakage Under the Hood

If you see greasy liquid around the AC lines, compressor, or even inside your car, you may have a leak.

5. Visible Ice on AC Compressor

If there is no more freon, there is only water left. If there is no freon in the water, it will start to freeze. The water will start to freeze first around or on the compressor.

How to Check Your Freon Level

How To Check Freon Levels In Car-3

If you notice any of the above, it’s time to check the level of freon in your air conditioner.

Follow this step-by-step guide to do it right and safely.

Step 1: Open the Hood and Find the Low-Pressure Port

Your car’s air conditioner compressor only squeezes the gas. Since it can’t compress liquids, you need to make sure that the compressor only gets freon.

Between the evaporator and the compressor is where you can find the low-pressure service port. The valve on the low-pressure service port of the bigger AC line is smaller than the valve on the high-pressure port of the smaller AC line.

You might see a “L” on the low-pressure service port, though not all cars have this.

Step 2: Turn on Your Vehicle and AC

To start the engine, turn the key. Turn the fans all the way up and turn on the air conditioner. Turn on Max-AC and recirculation, if they are available.

Step 3: Run a Low-Pressure Service Port AC Diagnostic

Keep the car running and connect the coupler that came with your refill kit to the low-pressure service port. Just take off the cap and push the coupler into the port until it fits.

When you check the levels, make sure the freon can is not connected.

You can take a reading once the pressure is on. It will tell you how much freon is in the AC unit of your car.

If the gauge shows a red number, there is too much freon in the system. This needs a different service, and a mechanic is usually the best person to take care of it.

If you were right when you thought your car had low freon, the gauge will show that the system has no freon or very little freon. Now you can start the process of recharging.

How to Recharge Your Car’s AC

Once you know that the problem is caused by low freon, it is time to recharge the system.

The first thing to do is get ready to add freon. This means that the coupler needs to be taken off the low-pressure service port.

Shake your R-134A freon can for a few seconds, then connect it to your gauge.

The coupler can then be put back on the port.

Make sure to keep the port facing up and never point the can in the wrong direction.

This could lead to liquid freon getting into your body. You need to make sure that the freon stays as a gas.

While the can is standing straight up, squeeze the trigger to let the freon out.

While the can is standing, you can keep shaking it.

After shaking the can, turn your wrist 90 degrees and move the can several times from a standing to a sideways position.

Just make sure that the can never faces down.

Take your finger off the trigger after about 10 seconds and look at the gauge. The needle should move from the “Low” zone to the “Green” zone.

Follow the steps from above, but make sure the freon gauge doesn’t reach the red area.

The AC compressor can be badly hurt by too much freon.

Why Freon Needs to be Replaced

It’s important to know that it’s normal for your car’s air conditioner to leak freon. Over time, the system will lose so much that the AC won’t work as well as it used to.

In some cases, the whole thing will stop working.

The good news is that if freon is the problem, it’s easy to fix, as the guide above shows.

But if you don’t think you can fix the problem yourself, you should take your car to a mechanic.

They will be able to figure out what’s wrong and add freon for you.

Remember that you can probably do this yourself and save a lot of money.

For many people, this is the best choice if their AC only has low or no freon.