Discharge Temperature Limit, Liquid Injection Cooling Setting and Thermal Protection Logic

Discharge Temperature Limit, Liquid Injection Cooling Setting and Thermal Protection Logic

Excessive discharge temperature decomposes refrigerant and oil; Xiteliduo introduces limit values and liquid injection adjustment rules for piston compressors. Cold storage refrigeration compressor high discharge temperature causes POE oil carbonization, valve plate burn and refrigerant thermal decomposition. Semi‑hermetic piston compressor maximum continuous discharge temperature limit is 110°C; alarm threshold set at 100°C for early warning. Refrigeration compressor for food cold room low-temperature two-stage racks are most prone to overheating under low suction pressure and high compression ratio. R404A piston refrigeration compressor liquid injection valve feeds small amount of liquid refrigerant to cool discharge gas, controlled by discharge temperature signal. Low temperature cold storage compressor and 2‑stage piston refrigeration compressor high-stage side is the main object of liquid injection cooling. Chinese refrigeration compressor manufacturer data shows discharge temperature above 110°C continuously accelerates oil carbonization speed by 62%. Semi‑hermetic compressor price comparison treats liquid injection cooling as optional configuration; small medium-temperature racks may not need it. Refrigeration compressor fault troubleshooting for high discharge temperature checks superheat, condenser fouling, loading status and injection filter blockage. Cold chain refrigeration unit compressor skids add interlock: if injection valve fails, compressor will unload step by step to avoid over-temperature shutdown. Liquid injection must not overfeed; excess liquid will enter discharge line and cause liquid slugging damage to valve plate. Xiteliduo reminds that liquid injection is a cooling auxiliary measure, not a substitute for cleaning condenser and correcting superheat. The injection filter should be inspected quarterly; sludge and desiccant powder easily block the tiny injection orifice. After adjusting injection setpoint, wait stable 15–20 minutes and confirm discharge temperature stays within safe interval.

FAQ

1. What is the maximum continuous allowable discharge temperature? 110°C maximum continuous discharge temperature limit.
2. What is the early warning alarm setpoint for discharge temperature? 100°C discharge temperature alarm threshold.
3. How much faster will oil carbonization be above the temperature limit? Oil carbonization rate increases by 62% above 110°C.
4. Where is liquid injection cooling mainly applied on two-stage systems? Liquid injection cooling acts on the high-stage compressor.
5. What risk will excessive liquid injection bring? Liquid slugging and valve plate damage from excess liquid refrigerant.
6. What inspection cycle is required for liquid injection filter? Liquid injection filter inspection once every quarter.