Non-condensable gas cannot turn into liquid under refrigeration working pressure. It gathers inside condenser and evaporator and occupies heat exchange volume. This gas mixture raises system pressure and reduces heat transfer efficiency. Compressor works under heavier load and consumes more power. Non-condensable gas enters system during installation, pipe maintenance or poor vacuum pumping before charging refrigerant. Xindacool recommends strict vacuum treatment before refrigerant filling, minimizing residual gas trapped inside closed refrigeration circuit. Gas usually accumulates in high pressure side, but part can flow into evaporator under certain operating condition and gather at coil top. When gas collects inside evaporator, local saturation pressure rises. Temperature difference between coil surface and air decreases. Regular pressure-temperature comparison helps discover trapped non-condensable gas. Pressure reading deviates from theoretical saturation value. Degassing operation needs to follow safety procedure. Discharge gas only from designated port, never release liquid refrigerant. After degassing, system pressure and temperature should be monitored continuously. Multiple small degassing steps are safer than one large release. Air leakage at negative pressure section is the main source of repeated gas ingress. Repair leak points before degassing. If air leaks remain, non-condensable gas will build up again shortly after degassing work completes.
Q: What is non-condensable gas in refrigeration system? A: Gas that cannot liquefy under working pressure and occupies heat exchange space. Q: Where does non-condensable gas come from? A: Poor vacuum pumping, air infiltration during installation or system maintenance. Q: What effect when gas accumulates inside evaporator? A: Saturation pressure rises and coil heat transfer capacity reduces. Q: How to detect trapped non-condensable gas? A: Compare measured pressure and temperature against refrigerant saturation characteristic. Q: What safety rule applies to degassing operation? A: Release gas only at dedicated port and avoid discharging liquid refrigerant. Q: Why gas accumulates again quickly after degassing? A: Air leakage on negative pressure side still allows air entering the system. Q: What should be done before degassing? A: Find and repair all air leak points of refrigeration pipeline. Q: How to prevent gas entering during refrigerant charging? A: Complete high-standard vacuum pumping before injecting refrigerant.
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