Air to Water and Air Heatpumps. Full capacity heating and cooling on forced air system or hydronic and domestic hot water production in 3 to 6T. 3TR – Air to Air and Water Heatpump – ATF-45-HACW-1T-C-Combo $20,775.00 4TR – Air to Air and Water Heatpump – ATF-55-HACW-1T-C-Combo $23,312.00 5TR – Air to Air and Water Heatpump – ATF-65-HACW-1T-C-Combo $26,125.00 6TR – Air to Air and Water Heatpump – ATF-75-HACW-1T-C-Combo $26,793.00