The Refrigeration Cycle

The compression cycle and its four core processes, what each component does, the P-T relationship, superheat, subcooling and flash gas.

5 guides

• Flash Gas — What It Is, Where It Belongs, and Where It Doesn't
  What flash gas is, why a normal amount forms at the metering device, and why flash gas in the liquid line before the metering device is a problem that kills capacity.
• The Four Core Processes of the Vapor-Compression Cycle
  A plain-language walkthrough of the four core processes in every air conditioner and heat pump — compression, condensing, metering, and evaporating — and what each major component does to move heat.
• The Pressure-Temperature Relationship and What Saturation Means
  Why pressure and temperature are locked together for a boiling/condensing refrigerant, what saturation means, and how to use that relationship to read your gauges and find superheat and subcooling.
• What Subcooling Is and What It Tells You About the System
  What subcooling measures, how to calculate it from liquid-line pressure and temperature, and how it reveals condenser performance and refrigerant charge on a TXV system.
• What Superheat Is and Why It Protects the Compressor
  What superheat actually measures, how to calculate it from suction pressure and line temperature, and why a healthy superheat keeps liquid refrigerant out of the compressor.

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