1. What Is Subcool?

Subcool is the difference between the actual liquid temperature and the saturation temperature at a given pressure in a refrigeration system. It indicates how much the liquid has cooled below its saturation point.

2. How To Calculate Subcool?

The formula to calculate subcool is:

Where:

• Condensing Temp — The temperature at which refrigerant condenses at a given pressure
• Liquid Temp — The actual temperature of the liquid refrigerant line

Explanation: Subcooling ensures that only liquid enters the expansion device, preventing flash gas and improving system efficiency.

3. Importance Of Subcool Measurement

Details: Proper subcool is critical for refrigeration and air conditioning system performance. It indicates whether the system has the correct amount of refrigerant and if the metering device is working properly.

4. Using The Calculator

Tips: Enter both temperatures in the same unit (Fahrenheit or Celsius). The condensing temperature should be higher than or equal to the liquid temperature for a valid calculation.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical subcool value for HVAC systems?
A: Most systems operate with 8-12°F (4-7°C) of subcool, but always consult manufacturer specifications for exact values.

Q2: Why is subcool important in refrigeration?
A: Subcool ensures liquid refrigerant enters the expansion device, preventing vapor flash and maintaining system efficiency.

Q3: How do I measure condensing temperature?
A: Use a temperature probe on the condenser outlet or convert pressure reading to temperature using a PT chart.

Q4: What causes low subcool?
A: Low subcool typically indicates undercharge, restricted liquid line, or faulty metering device.

Q5: What causes high subcool?
A: High subcool usually indicates overcharge, condenser problems, or restricted airflow.