DOE Finalizes Energy Conservation Standards for Consumer Gas-Fired Instantaneous Water Heaters

On December 26, 2024, the Department of Energy (DOE) issued a final rule amending energy conservation standards for consumer gas-fired instantaneous water heaters (GFIWH). Earlier this year, DOE finalized a new energy efficiency standard for other consumer water heaters but did not finalize the proposal for GFIWH.

Key Highlights of the Final GFIWH Rule

1. Scope of Coverage:

   1. Applies to gas-fired instantaneous water heaters with less than 2 gallons of effective storage volume and input ratings greater than 50,000 Btu/h.

   2. Standards are expressed using the Uniform Energy Factor (UEF), transitioning from the older energy factor (EF) metric.

2. New Standards:

   1. UEF levels are established based on draw patterns (Very Small, Low, Medium, High). For example:

      1. Very Small draw pattern: UEF = 0.89

      2. High draw pattern: UEF = 0.93

3. Compliance Date:

   1. Compliance is based on the date of manufacture, and this new requirement will apply to all GFIWH manufactured after December 26, 2029.