Superheat Calculator
Superheat is how many degrees the suction vapour is above its saturation (boiling) temperature at the measured pressure.
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 the saturation temperature from your gauge set or the refrigerant's P-T chart for the measured pressure.
Formula
- Superheat = suction line temperature − saturated suction temperature
Example calculation
Suction line 52 °F, saturation 40 °F → 12 °F superheat.
Practical HVAC use
Check evaporator feed and charge on fixed-orifice systems (against the manufacturer's chart) or TXV performance.
Common mistakes
- Reading saturation from the wrong refrigerant P-T chart.
- Measuring line temperature with a poorly insulated clamp.
- Using a single target for every system — targets come from the manufacturer.
Related lessons
Related calculators
Subcooling
ProCalculate liquid-line subcooling from saturated condensing temperature and liquid line temperature.
Evaporator TD
ProCalculate evaporator TD — the difference between entering air temperature and saturated evaporator 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