Raypack Raytherm Model H3-400 Hot Water Heater / Low Pressure Boiler, 2-stage Hydronic Heating Boiler. Rated for 327 lbs/hr relief valve capacity, 160 PSI, 31 sq. ft. heating surface, 327,000 BTU/HR output, 399,000 BTU/HR input, 200,000 BTU/HR minimum input. Unit is a natural gas-fired boiler with max water temp of 250 deg. F. Includes plate type heat exchanger measuring 7.50" long X 19" wide, and 2" inlet/outlet. Previously used in food operation. Part Number 901613. Serial number 0403218690. ASME code constructed, National Board number 218690. Appears to be unused.