Hot watersteam type for central heating plants casing : powder coated g.i.sheet.Element : seamless copper pipe(1-38 and 0.04 thick) aluminium fins(4-14*4-14 and 0.02 thick) . capacity hot water : 4000 btuhr(1000 kcalhr) to 16000 btuhr(4000 kcalhr) steam : 5600 btuhr(1400kcalhr)to 22400 btuhr(5600 kcalhr)