Approach Temperature Calculator
Calculate condenser or evaporator approach temperature from refrigerant saturation pressure and measured air temperature for faster HVAC field diagnostics.
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Frequently asked questions
What is condenser approach temperature?
Condenser approach is the difference between condensing saturation temperature and outdoor air temperature at the condenser. It is commonly used as a quick field check of heat rejection performance.
What is evaporator approach temperature?
Evaporator approach is the difference between return air temperature and evaporating saturation temperature. It can help a technician quickly evaluate evaporator coil performance and airflow-related issues.
How does this calculator find saturation temperature?
The calculator uses the selected refrigerant and the entered gauge pressure to estimate saturation temperature, then compares that temperature to the measured air-side reference temperature.
Does approach temperature replace superheat or subcooling?
No. Approach temperature is a fast diagnostic helper, not a replacement for manufacturer charging procedures. Final charging and system evaluation should still use the proper superheat, subcooling, airflow, and installation checks.
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