This report presents accomplishments in the area of pulse combustion based, high efficiency commercial/industrial water heaters with targeted inputs of 500, 750, and 1,000 MBtu/h (146,438; 219,656; 292,875 W).

Two engineering models were completed, one for a single 500,000 Btu/h (146,438 W) input and one capable of firing all three targeted inputs with only minor adjustments. Both models have efficiencies exceeding the target of 90%. Acoustic work, cost reduction efforts, and development of accessories are planned prior to field testing.

Units: Dual