Direct Heating Equipment


Direct heating equipment are small heaters that are located in the space to be heated and can be either permanently installed or portable. Common names for this equipment include space heaters, wall heaters, floor heaters, and room heaters. They are predominantly fired with natural gas or propane — some require electricity for certain operations like fan motors or electrical vent dampers — and only these units are covered by federal standards.


On April 16, 2010, DOE issued a final rule for amended standards for residential direct heating equipment. The standards depend on unit type and input capacity, with the AFUE ranging from 57% for a small floor unit to 76% for a large, fan-assisted wall unit. The standards will become effective April 16, 2013. According to DOE, the standards will save .2 quads of energy over 30 years, consumers will save about $500 million and carbon dioxide emissions will be cut by about 9 million metric tons.

In October 2015, DOE initiated a rulemaking to develop updated standards for direct heating equipment.


Baseline direct heating units generally consume 200–300 therms annually, depending on the type of unit. Based on the maximum technologically-feasible efficiency levels identified by DOE, there is potential to further reduce energy use by up to 28% depending on the specific product. Manufacturers improve the AFUE of direct heating equipment primarily through improvements in the heat exchanger design, though the DOE has identified a dozen other technology options that can also improve efficiency. These improvements include, but are not limited to: electronic ignition (part of the proposed standard), improved fan or blower motor efficiency, thermal or electric vent damper, and induced draft.

Projected Savings

Savings through what year?:
Energy saved (quads):
CO2 savings (million metric tons):
Net present value savings ($billion) 3% discount rate:
Net present value savings ($billion) 7% discount rate:


Federal Date States
Potential Effective Date of Updated Standard 2024
Updated DOE Standard Due 2021
Test Procedure - Last Revised - Standby/Off Mode 2012
2nd Federal Standard Adopted (DOE) 2010
Test Procedure - Last Revised - Active Mode 1997
1st Federal Standard Effective 1990
1st Federal Standard Adopted (Congress) 1987
NAECA Initial Federal Legislation Enacted 1987

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