Superheat Subcooling PT Chart

The HVAC tech's superheat & subcooling calculator — charge diagnosis and PT chart in one honest tool.

Pick the refrigerant, enter your gauge pressure and line temperature, and read superheat, subcooling and saturation temperatures live. Choose the charging method — TXV/EEV (subcooling) or fixed orifice (superheat) — and get a clear verdict against the target: on target, check, or off target, with the direction: add charge or recover charge. A built-in PT quick-look table shows saturation temperatures around your reading, with separate dew/bubble columns for zeotropic blends.

Works in °F/psi or °C/bar — one global toggle.

FREE
• R-410A with full superheat, subcooling and TXV charge diagnosis
• PT chart around your gauge reading
• Share results as text

PRO
• All 7 refrigerants: R-410A, R-32, R-454B, R-22, R-134a, R-407C, R-404A
• Fixed-orifice target superheat table (indoor wet-bulb × outdoor dry-bulb)
• Save readings to history
• Share clean PDF reports

Built for gloves and rooftop sun: big keypad, huge results, Outdoor Bright mode.

Everything stays on your phone — fully offline, no account, no tracking.

Results are a field aid; always verify targets with the manufacturer's data.

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