Indoor Design Conditions

By default CoolCalc Manual J uses the ACCA specified indoor design conditions of 70F (heating) and 75F (cooling). Cooling indoor relative humidity (RH) defaults to 50% in most climates. In dry climates - typically characterized by dry coil cooling operation - cooling indoor RH defaults to 45%. 55% RH should only be selected in very humid climates and when infiltration is an issue in the home due to a poor or leaky thermal envelope.

Indoor Design Conditions- CoolCalc Documentation