Subcooling Calculator
Subcooling is how far the liquid refrigerant has been cooled below its condensing saturation temperature.
HVAC Pro calculator — inputs, formula and example are open to everyone.
Result
Results for this calculator are part of HVAC Pro
You can see the inputs, formula and worked example. Unlock results for every Pro calculator.
Unlock with HVAC ProAlready a member? Sign in
Enter saturation temperature from your gauges or the refrigerant's P-T chart.
Formula
- Subcooling = saturated condensing temperature − liquid line temperature
Example calculation
Saturation 105 °F, liquid line 95 °F → 10 °F subcooling.
Practical HVAC use
Charge TXV/EEV systems to the manufacturer's subcooling target and diagnose overcharge or restrictions.
Common mistakes
- Measuring liquid temperature far from the pressure tap.
- Charging in very low ambient without manufacturer guidance.
Related lessons
Related calculators
Superheat
ProCalculate refrigerant superheat from suction line temperature and saturated suction temperature, in °F and K.
Condenser Split
ProCalculate condenser split: saturated condensing temperature minus outdoor ambient temperature.
Compression Ratio
ProCalculate compressor compression ratio from suction and discharge gauge pressures converted to absolute pressure.
Educational tool. Results are estimates from the stated formulas; always confirm with manufacturer data and the code adopted in your jurisdiction. All calculators