Commercial CAC and HP (65,000 Btu/hr to 760,000 Btu/hr)


Commercial unitary air conditioners (CUACs) and heat pumps (HPs), often called roof-top units (RTUs), are typically used to cool small- to mid-sized commercial buildings such as schools, restaurants, big-box stores, and small office buildings. They reject heat to the atmosphere by blowing outside air over the condenser coil. CUACs may also contain a gas heating section.


The Energy Policy Act (EPAct) of 2005 updated the original 1992 federal efficiency standards for CUACs and HPs with cooling capacities from 65,000-240,000 Btu/hr, and established new standards for equipment with capacities from 240,000-760,000 Btu/hr. The EPAct standards took effect on January 1, 2010. Cooling capacity represents the amount of heat that an air conditioner or heat pump can remove from an enclosed space per hour. The cooling efficiency of CUACs and HPs is currently measured by the energy efficiency ratio (EER), which is the cooling capacity (in Btu/hr) divided by the power input (in watts). The heating efficiency of HPs is measured by the coefficient of performance (COP), which is the heat delivered (in Btu) divided by the energy input (in Btu). These standard levels are the same as those published in the commercial building energy code, ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) 90.1 in November 2010.

In April 2015, DOE formed a working group to negotiate potential new energy conservation standards for commercial CUACs and HPs with cooling capacity of 65,000 to 760,000 Btu/hr. The working group recommendations were ultimately adopted by DOE in a December 2015 final rule. The two-stage standard is based on a metric called IEER (integrated energy efficiency ratio), which captures efficiency at 25, 50, 75, and 100% of full capacity, better reflecting the range of operating conditions. The first stage requires that new rooftop air conditioners meet the efficiency levels in ASHRAE 90.1-2013, about 10% more efficient than current standards. The second stage requires minimum IEER levels of 12.3 to 14.8 (depending on equipment type and capacity), about 25-30% more efficient than the 2010 minimum standards. DOE estimates that over the lifetime of units sold over thirty years, the proposed standards would save businesses nearly $50 billion (at 3% discount rate) and reduce electricity consumption by about 15 quadrillion Btu, more than any other efficiency standard ever adopted by DOE. The first stage was effective January 1, 2018 and the second is effective January 1, 2023. 


Technology options for improving the efficiency of CUACs and HPs include higher efficiency compressors, compressor staging, larger and better heat exchangers, higher efficiency fan motors and fan blades, and improved expansion valves. DOE’s High Performance Rooftop Unit Challenge has helped spur several manufacturers to develop and bring to market high-efficiency rooftop air conditioners. Equipment on the market today achieves IEER levels as high as 21.

Savings through what year?: 2048
Energy saved (quads): 14.8
CO2 savings (million metric tons): 873
Net present value savings ($billion) 3% discount rate: $50
Net present value savings ($billion) 7% discount rate: $15.2


Fact Sheets


ASAP Press Releases


Standards in the News


Federal Date States
Potential Effective Date of Updated Standard 2029
Updated DOE Standard Due 2024
Potential Effective Date of Updated Standard 2019
3rd Federal Standard Effective 2018
3rd Federal Standard Adopted (DOE) 2016
Updated DOE Standard Due 2016
Test Procedure - Last Revised - Active Mode 2016
2010 AZ Standard Effective *
2010 RI Standard Effective *
2010 NY Standard Effective *
2nd Federal Standard Effective 2010
2009 CT Standard Effective
2005 MD Standard Effective
2005 AZ Standard Adopted
2005 RI Standard Adopted
2005 NY Standard Adopted
2nd Federal Standard Adopted (Congress) 2005
2004 CT Standard Adopted
2004 MD Standard Adopted
1st Federal Standard Effective 1994
1st Federal Standard Adopted (Congress) 1992
EPACT Initial Federal Legislation Enacted 1992

* State standard never went into effect due to preemption by federal standard.

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