How to Charge a PTAC Unit

Written By
Charles Poole
Charles Poole
Published: Aug 26, 2011
Updated: Nov 20, 2021
2 minute read

You don’t have to be an HVAC technician to charge your PTAC unit. You can do it yourself with little hassle.

Things You Will Need

  • Towel
  • Screwdriver
  • Canned refrigerant
  1. Unplug the PTAC unit from the power outlet in the room and then remove it from the window. Put a towel down and then place the unit on the towel to soak up any water leaks that may occur.

  2. Use a screwdriver to remove the screws on the back panel of the unit casing. Remove the back panel of the unit casing to gain access to the inner components of the unit. Look for the compressor inside the unit; this is a metal cylinder that has two hoses coming off of it.

  3. Connect your can of refrigerant to the service valve coming off of the compressor. The service valve is the larger of the two valves. The service valve is the larger valve on the end of the can’s hose.

  4. Connect the other hose to the smaller valve on the compressor. Turn on the AC unit and allow the unit to charge. The unit will automatically fill with the amount of refrigerant needed. When you feel cold air coming out of the unit, it is done charging.

  5. Remove the can of refrigerant. Replace the metal casing on the back of the unit and replace the screws keeping it in place. Put the PTAC unit back into the window.

The Drip Cap

  • PTAC units are more widely known as window units.
  • If the PTAC unit is not cooling the room, you may need to charge it with more refrigerant.
  • This refrigerant is what allows the air to cool inside the unit.
  • Use a screwdriver to remove the screws on the back panel of the unit casing.
  • The service valve is the larger of the two valves.
Charles Poole

Charles Poole holds a Bachelor of Arts in creative writing from Appalachian State University. He started freelancing in college for local publications in Boone, N.C. and is continuing his career through online freelancing with a…

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