hot sales KFXY-036UCII pool water heater heat pump for school 1) PVC Titanium heat exchanger with full resistance against corrosion, more durable. 2) Compact structure, easy demountable for access. 3) High efficiency compressor, saving energy. 4) Flow switch for water flow protection. 5) Intelligent controller and adjustment by quick mind microprocessor. 6) Intelligent LCD display wired controller. 7) Air exchanger (fins-coil )with hydrophilic coating. 8) Automatic defrosting function included. Optional: R410a, R22, R407c refrigerant is available.