Definition: Cooling liquid refrigerant below its condensing temperature while maintaining high pressure. Typically 3-10°C of subcooling at condenser outlet.
Why It Matters:
- Ensures liquid refrigerant reaches expansion device (prevents flash gas)
- Improves system efficiency and capacity
- Too little subcooling indicates low refrigerant charge
- Too much subcooling may indicate restricted condenser
Measurement: Temperature difference between actual liquid refrigerant temperature and saturation temperature at measured pressure.
Related Terms: Superheat, Condenser, Refrigerant Charge