Commercial Water Heaters


Commercial water heating equipment includes a wide range of equipment that heats potable water for purposes other than space heating. Businesses with commercial water heaters range from office buildings, which typically use very little hot water, to restaurants, which may use large volumes. 


The current standards for most types of commercial water heaters took effect in 2003. The standards require a minimum thermal efficiency level of 80%. DOE finalized amended standards in 2023, which require compliance starting October 6, 2026. Once the updated standards take effect, new commercial gas-fired water heaters will be required to meet a minimum thermal efficiency of 95% or 96%, depending on the equipment type, effectively requiring the use of condensing technology.


Although there are electric and oil-fired commercial water heaters, gas-fired equipment accounts for most of the energy consumption of this product category.


Federal Date States
Potential Effective Date of Updated Standard 2021
Updated DOE Standard Due 2018
Test Procedure - Last Revised - Active Mode 2004
2nd Federal Standard Effective 2003
2nd Federal Standard Adopted (DOE) 2001
1st Federal Standard Effective 1994
EPACT Initial Federal Legislation Enacted 1992
1st Federal Standard Adopted (Congress) 1992

Timeline reflects state standards from 2001 to present; federal standards from inception to present.