1. WOTAC air to water heat pump has been tested and designed in accordance with European standard EN14511. 2. Strong automatic defrost function. 3. Water flow switch inside for water flow protection 4. Can be used both heating and cooling 5. With the famous water pump inside 6. Uses World famous brand compressor. 7. Uses eco-friendly refrigerant R407c or R410a. 8. Stainless steel cabinet (Powder coated steel cabinet optional). 9. Air side fins heat exchanger with hydrophilic coating 10. LCD, Carel controller are both available. 11. Energy recovery exchanger inside for sanitary hot water is option. 12.With Kind of function such as: High Pressure, Low pressure, Over heating, Phase testing, Discharge Temp. etc. Heating Capacity 25.0KW~38.0KW. COP 3.7-3.9. Certificates CE,CCC, ISO9001. Carton box or plywood.