... user investmentpayback period, and dramatically reduces the amount of greenhouse gasses produced.2. EASY TO INSTALL. ... .No fuel required, best protection from the danger of oil leakage, fire, explosion etc.4. ALL ... durable vitreous enameled /stainless steel tank6. Full range of HPWH products covers Hosehold type,Commercial type, and ... ,school,hospital,etc Air Source Swimming Pool Heat Pump for commercial