R22 Pressure Chart Low Side

Epa certified, added some refrigerant. High side reads about 250 give or take at 90 degrees ambient temperature. Using an hvac refrigerant pressure temperature chart is necessary to be sure a unit is operating correctly. Below are three free pressure temperature charts that can be used to troubleshoot an hvac unit. Other sources give the low side.

At the low side, the r22 pressure can fall below 10. Pressure that is too much lower or higher shows there is a problem. The low pressure side is the larger of the 2 pipes coming out of or going into the outside compressor unit. The high pressure side is the small diameter line. The low pressure side carries r22 gas while the high pressure line carries r22 in a liquid state.