... .R134a refrigerant 3.Combo Type Electricity-assisant Combo type air source heat pump KR15/150DW-A Model number: KR15/150DW-A ... dry cellar, duple use way with one appliance.Energy is from inexhaustible resource of air. Easy installation by Combo Type, safe ... , high efficiency and green for environment. Wide environmental temperature use from -15°C to +43°C with heating element, multiple protections ...