U.S. Department of Energy - Energy Efficiency and Renewable Energy

Federal Energy Management Program

New and Underutilized Technology: Condensing Water Heaters (Gas)

The following information outlines key deployment considerations for condensing water heaters (gas) within the Federal sector.


Condensing water heaters (gas) condense water out of the flue gas to achieve higher efficiencies.


Condensing water heaters are applicable in most building categories with tank type water heaters.

Key Factors for Deployment

FEMP designated purchasing specifications require Federal agencies to purchase commercial gas storage water heaters with an efficiency of 94% or greater when they have an input of 75,000 Btu/h or greater. Effectively, this means that these models must be condensing water heaters.

Ranking Criteria

Federal energy savings, cost-effectiveness, and probability of success are ranked 0-5 with 0 representing the lowest ranking and 5 representing the highest ranking. The weighted score is ranked 0-100 with 0 representing the lowest ranking and 100 representing the highest ranking.

Federal Energy Savings Cost Effectiveness Probability of Success Weighted Score
0.8 5.0 5.0 58