AC gas refill

Refilling AC gas ( recharging refrigerant) is an important maintenance task for air conditioners (both split and window types). As an AC technician, you likely know the safety protocols, but here’s a detailed, step-by-step guide on how to properly refill AC gas in a split or window AC unit. This guide assumes the use of R-22 or.R-410A . R32 refrigerants, which are the most common types.

What we use when we work!

• Manifold gauge set (with low, high, and center hoses)
• Vacuum pump
• Refrigerant cylinder (R-22, R-410A, R32 or others depending on the system)
• Clamp meter or digital thermometer (to check superheat/subcooling)
• Leak detector or soap solution
• Safety gear (gloves, goggles)

Diagnose the System

Check for symptoms like poor cooling, ice on coils, or hissing noise.

Measure the pressure with a manifold gauge.

If pressure is low, there could be a leak — do not refill until leaks are fixed.

Identify the Refrigerant Type

Check the nameplate or manual of the AC unit.

Ensure the cylinder contains the correct refrigerant ( R-22 or R-410A or R32)

Vacuum the System

• If it’s empty or after repairs)
  Connect the yellow hose to the vacuum pump.Turn on the pump and vacuum for 15–30 minutes to remove moisture and air.

  Check vacuum level (should reach 500 microns if using a micron gauge).

  Once done, close all valves on the manifold and turn off the pump.