Westcool PT Chart

Pressure and temperature

Fill either box

Refrigerant Pressure units

Pressure, kPa gauge

or

Temperature, degrees C

Superheat and subcooling

Same refrigerant as above

Superheat, at the suction

Suction pressure Suction line temp, C

Subcooling, at the liquid line

Liquid pressure Liquid line temp, C

Superheat is measured from the dew point, subcooling from the bubble point. On a blend with glide the tool uses the correct end for you, which is where most hand worked numbers go wrong.

Full chart

Bubble is the liquid saturation point, used for subcooling. Dew is the vapour saturation point, used for superheat. Greyed rows are below atmospheric, a vacuum on a gauge. Psig is shown alongside whatever unit you pick, unless you pick psi.