Target Superheat/Subcooling Calculator

Determine target superheat and subcooling values based on system type, conditions, and refrigerant.

TXV systems target fixed superheat. Fixed orifice/cap tube targets vary with conditions.
Outdoor wet bulb affects target superheat for fixed orifice systems. Measure with a sling psychrometer.
deg F
Indoor return air dry bulb temperature at the evaporator inlet.
deg F
Different refrigerants may have slightly different optimal targets.

Results

Target Superheat:
Ideal superheat reading at the evaporator outlet or compressor suction.
-deg F
Superheat Range:
Acceptable superheat range. Outside this range indicates a problem.
-deg F
Target Subcooling:
Ideal subcooling at the condenser outlet or liquid line.
-deg F
Subcooling Range:
Acceptable subcooling range for proper system operation.
-deg F
Diagnostic Tips:
Common diagnostic guidance based on system type.
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Reference: ASHRAE Refrigeration Handbook. Carrier, Emerson Climate superheat charging charts.