On this page
- Two covered products, two sets of rules
- CEER is the number the rules are written in
- The window unit standard
- The portable unit standard and SACC
- ENERGY STAR and FEMP sit above the federal floor
- Where the numbers appear: the EnergyGuide label
- What the standards do not decide
- Which to choose
- Questions people ask
Two covered products, two sets of rules
The Department of Energy treats a room air conditioner and a portable air conditioner as separate covered products, and the definitions decide which rule applies. A room air conditioner is an encased assembly built to mount in a window or through a wall, powered by single-phase current, with its own source of refrigeration and possibly a means of ventilation or heating. A portable air conditioner is a portable encased assembly that delivers cooled air to an enclosed space and is not a packaged terminal unit, a room air conditioner or a dehumidifier.
That split matters when you read a spec sheet. The two products are rated with different procedures, their capacity numbers are not the same thing, and the compliance dates differ. This site covers window and portable units with a stated BTU cooling capacity, so the window rule is the one that applies to the window models discussed here, and the portable rule is the one that applies to the portables.
| Item | Room air conditioner | Portable air conditioner |
|---|---|---|
| Governing standard | 10 CFR 430.32(b) | 10 CFR 430.32(cc) |
| Rating method | Appendix F, Subpart B of Part 430 | Appendix CC, Subpart B of Part 430 |
| Efficiency figure | CEER, in Btu/Wh | CEER, in Btu/Wh |
| Capacity figure | BTU cooling capacity | SACC |
| Compliance date | Required since 1990 | January 10, 2025 for units made on or after that date |
CEER is the number the rules are written in
Both rule sets use the combined energy efficiency ratio, written CEER and expressed in Btu/Wh. The FTC's Energy Labeling Rule names CEER as the efficiency descriptor for room and portable air conditioners, which is why the figure turns up on the EnergyGuide label and on maker listings. A higher CEER means more cooling for the same electricity under the DOE rating conditions. It is one number for the whole unit, not a statement about a single component.
Because CEER is a ratio, it compares fairly only between units rated the same way. A window unit's CEER and a portable unit's CEER come from different procedures, Appendix F and Appendix CC, so read each within its own product type. CEER explained goes further into how the figure is built and why the label shows it.
The window unit standard
Residential room air conditioners have been subject to DOE energy conservation standards since 1990, and the current requirements sit at 10 CFR 430.32(b). Manufacturers show compliance by following the rating method in 10 CFR 430, Subpart B, Appendix F. In practice, a window unit sold in the US carries a CEER that meets or beats the floor the section sets for it, and that same figure is what the label discloses.
The regulation states the floor a compliant model must reach; the model's own CEER appears on its label and usually on the maker's listing. Those are the two figures to put side by side. When comparing window models, BTU and SACC ratings explained covers the capacity side, and the efficiency side is the CEER figure.
The portable unit standard and SACC
Portable air conditioners got their own federal standards later. DOE's final rule for portables is dated January 10, 2020, and compliance with the standards in it was required on and after January 10, 2025. The regulation at 10 CFR 430.32(cc) covers single-duct and dual-duct portable units manufactured on or after that date and requires a CEER, in Btu/Wh, no lower than the floor it states.
Portables are rated with a different procedure, Appendix CC, and their capacity figure is the seasonally adjusted cooling capacity, SACC. For single-speed portables, SACC is determined under Appendix CC; for variable-speed portables the regulation uses SACC Full. That is why a portable's capacity is quoted as SACC in DOE terms and as a BTU figure in the product name, and why the two should never be converted into each other or compared across product types.
DOE has also published a Federal Register notice in May 2025 proposing to withdraw its earlier determination that portable air conditioners are covered products. A proposal is not a change to the regulation text: the current eCFR version of 430.32(cc) still sets the portable floor. A shopper who reads about the proposal should check the current regulation rather than assume the requirement has gone.
ENERGY STAR and FEMP sit above the federal floor
ENERGY STAR certification is a separate, voluntary level above the federal minimum. Its room air conditioner criteria list CEER base levels by capacity band and by unit type: casement-only units, for example, are listed at 12.8 and casement-slider units at 14.0. A model has to reach the level for its own band, so the badge stands for different CEER figures on different sizes.
The criteria also describe features that come with certification: an Energy Saver mode that limits fan operation when the compressor stops and is the default setting, and a filter reminder that signals when the filter needs checking, cleaning or replacing. What ENERGY STAR means for a room AC walks through the criteria, and the ENERGY STAR window units list collects models whose listings state the certification.
The Federal Energy Management Program publishes purchasing guidance for agencies, and its scope is narrower than the whole market. It covers casement-only and casement-slider window units, through-the-wall units and reverse cycle models, and it excludes portable air conditioners, packaged terminal units and models with electric resistance heating elements. Its worked example uses a 12,000 Btu/h unit run for 750 hours a year over a 9-year life, with CEER figures of 15.4 for the best available model, 14.7 at the ENERGY STAR level and 10.9 for a less efficient unit, and annual energy use of 584, 612 and 826 kWh respectively.
Where the numbers appear: the EnergyGuide label
The FTC's Energy Labeling Rule, 16 CFR Part 305, sets what an EnergyGuide label must show for room and portable air conditioners, and section 305.18 covers the label content for both. The rule also requires labels to be provided on websites under section 305.9, which is why a maker's product page often carries the same efficiency figures as the sticker on the unit.
That gives two places to check a claim: the labeling rule says what must be disclosed, and the DOE regulation says what the floor is. If a listing states a CEER, it should match the model's label. If a listing is silent, the label is the document to look for, and the room AC terms glossary covers the other abbreviations that appear beside it.
What the standards do not decide
Compliance says nothing about whether a unit suits a room. FEMP's guidance warns that oversizing a room air conditioner raises energy consumption and hurts humidity removal, because the compressor cycles on and off too much. What happens when a room AC is too big covers the symptoms, and choosing BTU for room size covers matching capacity to the size of the room.
Efficiency also does not settle the portable question. Two portables with the same SACC can differ in hoses, drain handling and noise, and a dual-hose model moves heat out of the room differently from a single-hose one. Single-hose vs dual-hose explains that difference. Read the CEER or the SACC as one input among several, not as a verdict on the unit.
Which to choose
| If you | Look for |
|---|---|
| If you are buying a window unit | Look for the CEER on the label and check it against the floor in 10 CFR 430.32(b). |
| If you are buying a portable | Compare SACC, not the BTU figure in the product name, and check the CEER against the floor in 10 CFR 430.32(cc). |
| If you want more than the federal minimum | Look for a listing that states ENERGY STAR certification and the CEER base level for its capacity band. |
| If a portable listing shows no SACC | The maker does not list one, so do not compare its BTU figure with another portable's SACC. |
| If you are matching a unit to a room | Size it with the ENERGY STAR guidance FEMP points to, and avoid oversizing, which FEMP ties to excessive on-off cycling. |
Questions people ask
Do portable air conditioners have federal efficiency standards?
Yes. DOE set the portable standards in a final rule dated January 10, 2020, and compliance was required on and after January 10, 2025. The regulation at 10 CFR 430.32(cc) covers single-duct and dual-duct portable units made on or after that date and sets a CEER floor in Btu/Wh.
Why does a portable list SACC instead of BTU?
SACC is the capacity figure DOE uses for portables, determined under Appendix CC of Subpart B of Part 430. For single-speed portables the figure is SACC; for variable-speed portables the regulation uses SACC Full. Never convert a BTU figure into SACC or estimate one from the other.
What does CEER measure?
CEER is the combined energy efficiency ratio, expressed in Btu/Wh. The FTC's Energy Labeling Rule names it as the efficiency descriptor for room and portable air conditioners. A higher CEER means more cooling for the same electricity under the DOE rating conditions.
Are ENERGY STAR levels the same as the federal minimum?
No. ENERGY STAR is a separate, voluntary set of criteria with CEER base levels listed by capacity band and unit type, such as 12.8 for casement-only and 14.0 for casement-slider units.
Does the standard decide what size unit to buy?
No. The standards govern efficiency, not sizing. FEMP's guidance notes that oversizing raises energy consumption and hurts humidity removal through excessive on-off cycling, so capacity has to be matched to the room separately.
Where is a model's CEER shown?
On the EnergyGuide label. The labeling rule at 16 CFR Part 305 covers room and portable air conditioners, and section 305.9 requires labels to be provided on websites, so the figure often appears on the maker's product page as well.