How to Check Freon in a Carrier HVAC System

Freon is no longer used in home or automotive air-conditioning systems because of the damage it causes to the ozone layer.
Prior to that discovery, it was considered a useful refrigerant because it wasn't toxic, flammable or corrosive. But now that it is banned, your system isn't likely to still have it. Replacement refrigerant gases act in a similar fashion to Freon in that they pull heat out of the air and displace it, making your home cooler as a result. The process of checking the coolant level in your Carrier HVAC system, whether it is Freon or an alternative, remains the same.

Step 1

Shut off the air conditioner so it isn't operational while you are checking the refrigerant.

Step 2

Attach the two hoses from the gauge manifold set to the pressure ports on the air-conditioner system. The gauges are designed for specific coolants to give you an accurate reading, so if your system does have Freon, the gauges should be designed for that. The hoses are designed for low and high pressure, with the low-pressure hose usually blue while the high-pressure hose is red. The blue hose connects to the larger port on the AC used for suction, while the red hose attaches to the smaller port used for liquid.

Step 3

Run the system for 15 minutes. This allows it to reach a stable operation state, so you get a more accurate measure of the refrigerant level.

Step 4

Read the gauges and check with your Carrier manual to verify that the levels are in the appropriate range, which varies by the size of your system. The readings are in psi, which are pounds of pressure per square inch.

Things You Will Need

  • Manifold gauge set and hoses

Tip

  • If your Freon levels are low, your system likely has a leak. The law requires you to have a licensed professional make the repair to prevent Freon from leaking into the environment.

Resources

About the Author

Michael Davidson started writing screenplays in 2003 and has had a screenplay professionally produced. He has also studied martial arts since 1990 and has worked as a licensed security specialist. Davidson has written articles for various websites. He is a graduate of Michigan State University and holds a Bachelor of Arts in advertising.