Room Air Conditioners


Room air conditioners (or window ACs) are designed to cool individual rooms and are mounted in a window or through a wall. Some models are capable of providing heating, but there is no standard for heating performance.


The current standards for room ACs took effect in 2014. For typical room ACs with cooling capacities less than 8,000 Btu/h, the minimum combined energy efficiency ratio (CEER) is 11.0.

DOE finalized new standards in 2023, which require compliance starting May 26, 2026. The new standards represent energy savings of 20-36%, depending on the product class, relative to the current standards and effectively require variable-speed compressors for larger units (>8,000 Btu/h).

*The energy efficiency metric, combined energy efficiency ratio (CEER), is expressed as the ratio of the cooling capacity (Btu/h) to the power input (W).


About 21% of all US households have at least one room AC unit, and about half of these households have two or more. Technology options for improving the efficiency of room ACs include more efficient compressors (including variable-speed compressors) and fan motors and improved heat exchangers.

Savings through what year?: 2043
Energy saved (quads): .31
CO2 savings (million metric tons): 17.4
Net present value savings ($billion) 3% discount rate: 1.5
Net present value savings ($billion) 7% discount rate: .6


Fact Sheets


ASAP Press Releases



Federal Date States
Potential Effective Date of Updated Standard 2022
Updated DOE Standard Due 2019
3rd Federal Standard Effective 2014
3rd Federal Standard Adopted (DOE) 2011
Test Procedure - Last Revised - Active Mode 2011
Test Procedure - Last Revised - Active Mode 2011
Test Procedure - Last Revised - Standby/Off Mode 2011
2nd Federal Standard Effective 2000
2nd Federal Standard Adopted (DOE) 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.