Super Heating Performance at Low Ambient Temperature Standard heat pump delivers best performance at 7°C ambient. Its efficiency drops significantly when the ambient temperature goes below 0°C, and when the ambient temperature goes below -5°C the heat pump generally will stop operation. DC inverter heat pump though has an enhanced heating ability at low ambient generated from a bigger output of compressor, its limited ambient temperature is only down to -10°C. EVI heat pump however has a super heating performance at even -15°C, which is realized through extra suction of compressor to increase the operating refrigerant. Specifications Model: HLRE-8 HLRE-25 Heating capacity: 10kw-28.2kw Cooling capacity: 8kw-24.5kw Rated power: 3.3-9.3kw Hot water inlet temperature: 55degree C Power supply: 220V/50hz, 380V/50hz For more detailed information, please feel free to contact us.