How the ratings are read

This page explains, once, what every figure on this site means and where it comes from. Product, class and line-up pages link here instead of repeating it.

Source and licence

All ratings come from the U.S. EPA ENERGY STAR Certified Heat Pumps dataset (data.energystar.gov, dataset 83eb-xbyy), downloaded on October 28, 2026, with rows last updated on October 27, 2026. This site calls that date "certified as of". EPA states that its data is in the public domain (17 U.S.C. § 105) and gives no warranty for it; neither does this site. The list changes every week, and the site is rebuilt from a fresh download.

Data: U.S. EPA ENERGY STAR Certified Heat Pumps dataset (data.energystar.gov, 83eb-xbyy), certified as of 2026-10-27. Rankings, groupings and ratios are computed by heatpumpratings.online. Not affiliated with or endorsed by EPA or ENERGY STAR.

What was kept

The file holds 285,115 rows. Listings sold only in Canada, rows without a heating capacity at 47°F, 17°F or 5°F, and a few rows with impossible values were removed. When the same outdoor, indoor and furnace combination is listed several times with ratings that disagree with a clear majority of its identical listings, the minority row was removed. That leaves 279,972 rows, 131,386 distinct certified matches and 7,820 outdoor model numbers.

Rated products

Outdoor model numbers whose best ratings are identical in every field (type, cooling capacity, SEER2, EER2, HSPF2, capacities at 47°F, 17°F and 5°F, COP at 5°F, compressor staging and refrigerant) are counted once, as one rated product. This merges listings with identical ratings under several brand names. There are 2,613 rated products. Every count, median and rank on the site counts rated products, not model numbers.

Names

EPA model numbers often contain wildcard characters such as * or [X]. Names in titles, headings and links drop trailing wildcards and show inner ones as an ellipsis (27VNA154A*030* becomes 27VNA154A…030). Each product page shows the exact string once, as "Model number as listed". Where two products would get the same short name, the name gets the year of its first market listing, for example "(2022 listing)". No name ends in an ellipsis.

Matches, best match and range

Ratings belong to certified matches: an outdoor unit with a named indoor unit, sometimes with a furnace, or with no indoor model named for multi-zone units. Headline figures are the best value among a product's matches, so they read as "up to". The lowest match is given next to it where the two differ.

Kept at 5°F

Listed heating capacity at 5°F divided by listed heating capacity at 47°F, in the same match, shown as a percentage. It can exceed 100% when a listing shows more capacity at 5°F than at 47°F. Output at 5°F is the listed capacity at 5°F in Btu/h. COP at 5°F is the listed coefficient of performance at 5°F and has no unit.

The EPA cold-climate designation

The designation is shown exactly as EPA publishes it for each match, and a product counts as designated when at least one of its matches is. EPA tests the designation against a nominal 47°F capacity, which can differ from the listed 47°F capacity. In 1,271 designated matches, spread over 57 rated products, the listed 5°F capacity is below 70% of the listed 47°F capacity. The designation still counts for those products, everywhere on the site, and their product pages state the range of that ratio next to it, as a plain number (for example "listed 5°F capacity: 55%–56% of its 47°F capacity").

SEER2, EER2 and HSPF2

Seasonal cooling efficiency, cooling efficiency at a single test condition, and seasonal heating efficiency, all in Btu per watt-hour and shown as published.

Size classes

Each product is placed in a band of its highest certified cooling capacity (Btu/h), not its nameplate tonnage. The bands follow clusters in the data. Split systems: under 15,000 (1-ton, ranked with 1.5-ton) · 15,000–19,999 1.5-ton · 20,000–25,999 2-ton · 26,000–31,999 2.5-ton · 32,000–38,999 3-ton · 39,000–43,999 3.5-ton · 44,000–49,999 4-ton · 50,000 and up 5-ton. Mini- and multi-splits (lower bound → class): under 7,500 → 6,000 · 7,500 → 9,000 · 10,500 → 12,000 · 13,500 → 15,000 · 16,500 → 18,000 · 20,500 → 24,000 · 25,500 → 27,000 · 28,500 → 30,000 · 31,500 → 36,000 · 39,500 → 42,000 · 45,000 → 48,000 · 51,000 and up → 60,000. Single-package units form one class. Classes are not a sizing guide.

Ranks, ties and the place gauges

Ranks are competition ranks within a size class unless a sentence names a wider group: 1st is the highest value; products with the same value share a joint place, and the next value takes the place after all of them. Each product page states one scope per measure. The tube gauges on product pages fill to the share of the other rated products in the same scope that list a lower value; a full tube means no other product lists more. Lead sentences name a rival product only as the runner-up, a tie partner or the leader above.

Which products have a page

A product gets a page of its own only when its data set it apart: at least three distinctive facts, such as a top-five place in its class or across its type, or an attribute held by at most a tenth of its class, and at least one top-five place in its class or across its type. Products that would read almost the same as another page are shown as a line on the stronger page. All other rated products are in the finder, the class tables and side by side.

Line-ups

Brand groups are brands with at least 15 rated products. Brands whose rated products overlap by 80% or more are merged into one group, named after its members. Line-up ranks compare the 124 groups.

What this site does not do

It does not show what equipment costs, does not estimate running costs or savings, does not size equipment and gives no installation or purchase advice. It is not affiliated with or endorsed by EPA or ENERGY STAR and does not use the ENERGY STAR mark.