Superheat & Subcooling Calculator — HVAC Charging
Do I charge by superheat or subcooling?
Charge by superheat on fixed-orifice (piston) systems and by subcooling on TXV/EEV systems. The metering device decides the method: a TXV actively controls superheat at the evaporator, so superheat will not track charge — subcooling at the condenser does. On a piston system there is no active control, so superheat is the reliable charging target.
Run the numbers for your project
Use the Superheat & Subcooling Calculator — HVAC Charging to get an exact answer for your inputs.
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