Description Overview 400 hp steam boiler National board no. 2271 Year built: 1994 Specifications Mawp 300 psi (can easily be rated as 150 psi by using 150 psi safety relief valves) Heating surface: 2,730 sq ft Steam output: 13,800 pph (divided by 34.5 = 400 hp) Included Items No control panels included