How To Recharge Car AC After Compressor Replacement

Already paid an amount for replacing the compressor of the car and now looking for a cheap way to recharge the AC? If so, then search no further because you are about to know the best way to restore your car’s AC after a compressor replacement.

If your car is not cooling down properly then maybe the compressor requires replacement. And then, you must recharge the ac after changing the compressor to start blowing the cold air again. People usually hire a mechanic for this procedure. But you will be happy to know that you can also DIY the project without paying for the mechanic.

Today we will tell you how to recharge car ac after compressor replacement. We will provide you an easy and step by step guide of doing the whole procedure below.

Before you start, you need to know how AC works to simplify the procedure.

How The Car’s AC Works

The car’s air conditioning doesn’t produce cold air as like as your home AC. It basically takes the moisture and heat from the air, which leaves the cool air in your car. Your car includes a refrigerant inside the AC which keeps fluid and gas at under pressure inside it. It keeps the gas under low pressure at 70psi when the system is not running. The amount of gas depends on the type of vehicle. The compressor compresses the gas into fluid when you turn on the system.

Then the fluid flow throws the condenser and removes the heat from the air and then come back to its previous gas state. Then it enters in the receiver drier to remove all the moisture. After that, it moves to the passenger compartment and removes the heat. That is how the ac of your car works.

How To Recharge Car Ac After Compressor Replacement

You will require the below components for the procedure.

  • Refrigerant gas.
  • Thermometer.
  • AC dispenser.
  • Safety Kits.


It is important to wear safety kits such as safety gloves, glasses while working on the project. The refrigerant gas sensitive to your skin, and it causes immense pain if it comes in touch to your skin. Also, read the user handbook that comes with the AC recharge kit as well as checks the warnings.


At first, you need to do is turning on the car. Start it and set the AC to high. Check whether your car’s AC compressor is engaging or not. There is a clutch at the end of the compressor. It should be spinning along with the accessory belt as the AC is set on high. If the clutch is indeed engaging then most probably, the system has low refrigerant. If the clutch is not correctly engaging, then the AC system is either has an electrical problem or little gas. You can be assured by adding new refrigerant.


It this step you will need to check the remaining. For this, turn off the car and locate the pressure port on the low side. It is usually situated on the passenger side of the engine bay. There will be an L letter on its cap. If you are struggling to find it, then you can try to find the two aluminum pipes. They should come out from the metal wall behind the engine. Amongst the two pipes, the larger one will lead you to the service port.


Put the quick connecting fit from the end of the recharge hose and push down gently until you hear a click sound. Make sure that you are not pressing the trigger before it is connected.


Now turn on the car and put the AC at high. Attach the gauge on the clutch and monitor the measurement. The pressure should be around 40 psi, which verifies that the air conditioning is undercharged.


Now thread the refrigerant on the recharge hose and top off the liquid refrigerant. After the installation, squash the trigger for a few seconds to add the liquid. Check the gauge to know you are done or not.

Now check the temperature. It should be okay. Else, your car’s AC has a different problem. Hopefully, the above guide will be helpful for you.

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