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Superheat and subcooling calculator
Diagnose the refrigerant charge of any system in seconds. Free, for HVAC-R technicians.
Superheat
Low side · suction line
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Enter the values
Subcooling
High side · liquid line
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Enter the values
Target and tolerance are expressed in degrees of the selected unit. The default target values are for reference only (systems with a thermostatic expansion valve): always prioritize the data on the nameplate or the equipment manufacturer's spec sheet. The pressure → saturation temperature conversion is a PT-chart estimate; for maximum accuracy, use the saturation temperature read directly from your digital manifold.
Save these diagnostics to the equipment's service record
With Lissi, every measurement is saved to the asset's history. Stop writing on paper that gets lost.
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