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2,632 basic models from 117 brands, 5,285 listed models. Updated Oct 26, 2026.

This site covers 2,632 basic models of water heater. You can search 5,285 model numbers, the kind printed on tags and quotes. There are more than twice as many model numbers as basic models.

Most basic models, 1,862 of them, are matched to test figures alone. Another 524 have those figures and an ENERGY STAR certified model number. A further 246 are ENERGY STAR certified, but no test record matched them. More ENERGY STAR certified basic models have a test record than do not.

There are 847 main pages here, one for each set of figures. Each of the other 1,785 pages shows a main page's full set of figures and points to it. That comes to about two in three of the basic model pages.

Certified figures

Every figure on this site is certified by the manufacturer to the U.S. Department of Energy. The tests follow the federal test procedure for water heaters. This site prints the figures as listed and adjusts nothing.

  • Size as sold: the stated size on a product's own page, where it names one size. Otherwise, a size in the model number counts when the certified volume is 85–105% of that size.
  • Label and volume: 1,623 tanks have both figures. The highest certified volume is below the sold size for 1,397 of them (86%).
  • Difference: sold size minus certified storage volume, only when both are single whole-gallon values. A positive difference means the certified volume is smaller. Ranges, fractions, and missing figures show a dash.
  • List totals: volume bounds use every listed volume of models with both figures. The lower middle difference is the median when the count is even. A size group names one sold size only when its models share it.
  • Storage volume: the tank volume the test measured. A tankless heater has none.
  • UEF, the uniform energy factor: the energy delivered in hot water, divided by the energy the water heater used, over a simulated day of use. A heat pump water heater can exceed 1.
  • Gallons per minute at a 67°F rise: the flow a tankless heater warms by 67°F in the test.
  • First-hour rating: the gallons of hot water a full tank delivers in its first hour of use.
  • Recovery efficiency: the share of the energy used to reheat the water that ends up in it.
  • Draw pattern: the daily hot water use the test simulates, from very small to high.

Basic models and listed models

A manufacturer certifies a basic model. It then lists every model number sold under that basic model. Each page here is one brand's basic model. Its table shows every listed model with that model's own figures.

A star in a model number stands for one character. A basic model whose number ends in stars has its page at the number without them. So GCRL-40 4** has its page at GCRL-40 4.

Brands

A basic model listed under several brands has a page under each brand. When pages carry every figure alike, each one names the others under "Also listed as." One of them is the main page. Nothing in the data says two brands sell one machine.

ENERGY STAR

A page shows ENERGY STAR certified models when EPA lists a model number that matches one of its listed models. A match needs the same brand, or a brand of the same family. A reviewed model-number map can also link a brand-coded model to a basic model in that family when only the documented brand code differs and every shared certified figure agrees. Those products name their certified basic model. 1,374 ENERGY STAR listings are matched this way.

ListingBasic models
Certified to DOE and ENERGY STAR certified524
Certified to DOE only1,862
ENERGY STAR certified, no DOE record matched246

Advertised figures

An advertised figure is one that a maker's own product page or spec sheet, or a store's listing, states for the model. Makers' pages were read directly. Store listings from The Home Depot, Lowe's, SupplyHouse, and Ferguson were read only from archived copies in Common Crawl and the Wayback Machine, never from the store, and each shows the date of its copy. Each figure is kept with its own words, at most 40 of them, and compared with the certified figure of the listed model the page names.

1,385 basic models show advertised figures, 217 of them from store listings. A figure a page gives for a whole product series is shown nowhere and compared with nothing.

Advertised tankless flow, counted exactly

  • Counted: 308 advertised flows. Each is a distinct gallons-per-minute figure that a maker's page or a store listing states for one gas or electric tankless model, with no basis on the page: no temperature rise, no inlet or outlet temperature, or an "up to" figure. Each counts once, whatever the number of listed models in the comparison.
  • Not counted: a flow stated with its rise or its temperatures, a flow given for a whole series, and a listing title's flow when the same listing states it with its rise.
  • Compared: the advertised flow divided by the certified flow at a 67°F rise of the listed model the page names, or of every listed model of the basic model when the page names none. A flow counts at 1.5 or more when the ratio is 1.5 or more.
  • Result: 288 of 308 (94%), over 230 tankless basic models. On makers' pages 191 of 202, in store listings 97 of 106.

See every tankless model's advertised and certified flow

Lists by type, size, and flow

Each type list holds every basic model of that type. Electric storage includes grid-enabled and tabletop tanks. A list sorts by size, smallest first, then by UEF, highest first, then by first-hour rating. A tank's size is the size it is sold as. A tankless heater's size is its certified flow at a 67°F rise.

The size a tank is sold as comes from the maker's page where the page states one size. Otherwise it is read from the model number, where the number carries a size the industry sells that fits the measured storage volume. A tankless heater falls in the group of its certified flow as printed, at one decimal. A basic model whose listed models differ falls in the group of its highest figure.

TypesGroupHolds models
Gas storage, electric storage, heat pump30-gallonin the 28-to-34-gallon group
Gas storage, electric storage, heat pump40-gallonin the 35-to-45-gallon group
Gas storage, electric storage, heat pump50-gallonin the 46-to-59-gallon group
Gas storage, electric storage, heat pump65-gallonin the 60-to-69-gallon group
Gas storage, electric storage, heat pump80-gallonin the 70-to-90-gallon group
Gas tanklessUnder 4.0 gallons per minutecertified below 4.0 gallons per minute
Gas tankless4.0 to 4.9 gallons per minutecertified at 4.0 to 4.9 gallons per minute
Gas tankless5.0 to 5.9 gallons per minutecertified at 5.0 to 5.9 gallons per minute
Gas tankless6.0 gallons per minute and upcertified at 6.0 gallons per minute or more
Electric tanklessUnder 1.0 gallon per minutecertified below 1.0 gallon per minute
Electric tankless1.0 to 1.9 gallons per minutecertified at 1.0 to 1.9 gallons per minute
Electric tankless2.0 gallons per minute and upcertified at 2.0 gallons per minute or more

A list appears in search results only where it has at least 8 basic models and differs from the list it narrows by at least 8. A list holding more than 75% of the list it narrows points search engines to that list instead. A list for a type that ENERGY STAR does not cover states that and lists nothing.

Each comparison page shows the model numbers of its type searched for most often in the United States, from Google Ads monthly search volumes measured in October 2026. A searched number is matched to every basic model whose model numbers it names. Models that carry every figure alike share one column.

Comparison charts

  • 2,479 model pages link to their chart point. The ring marks the chosen model and opens its draw pattern. Its position and the other dots stay the same.

Each dot on a comparison chart is one basic model. Tanks are drawn by first-hour rating against UEF, tankless heaters by flow at a 67°F rise against UEF. A basic model whose listed models differ is drawn at the listed model with the highest UEF, then the most output, so each dot is one listed model's own pair of figures.

A chart shows one draw pattern at a time, because a UEF compares only between models tested on the same pattern. It opens on the most common pattern among its models. A model with no draw pattern listed is counted under the chart and left off it. Solar heaters carry neither figure and are left off.

Two labels name the model with the highest UEF and the one with the most output. Where several models share that figure, the label counts them.

Brand comparisons

  • Pairs: both brands have at least 10 basic models on this site. Their water-heater comparison queries total at least 100 searches a month. Google Ads volumes were measured in October 2026. Close variants count once per query group. HVAC-only and water-softener queries do not count.
  • Median UEF: one observation per basic model, its highest listed UEF, with every listed model on the type's most common chart draw pattern. For an even count, the median averages the middle two values. Both brands need at least 5 models of the type and 5 observations on that pattern.
  • Output span: the lowest and highest listed first-hour volume or flow among all of the brand's models of that type.
  • Shared figures: a basic model counts when its full set of certified figures also occurs under the other brand. Each basic model counts once, including each brand's model in a shared set. This does not establish who makes the heaters.
  • Chart scales: each type and draw pattern uses the union of both brands' points to set the axes. Colors keep their fuel or heat pump meaning. Each brand's extreme labels refer to its own models.
Accepted brand comparisons and monthly searches
BrandsMonthly searchesModels with shared figures
A. O. Smith and Bradford White6102
A. O. Smith and Rheem2,9807
Bradford White and Rheem1,2405
Navien and Rinnai6900
Rheem and Rinnai4905
Rheem and Ruud480295

Model-number search

The search compares model numbers in capitals, without spaces, dashes, dots, slashes, or underscores. So RTGH-95DVLN-3 and rtgh 95dvln 3 match. A star in a listed model number stands for one letter or digit. A number typed in part matches every model number it begins. A brand name typed first narrows the matches to that brand.

Sizing

The sizing guide follows the method of the U.S. Department of Energy's Energy Saver page "Sizing a New Water Heater", read from its archived copy of Dec 30, 2024. A tank is sized by its first-hour rating against the home's busiest hour. A tankless heater is sized by the flow of the fixtures run at once and the temperature rise.

  • Gallons of hot water per use: shower 20, shave 2, hand dishwashing or food prep 3, automatic dishwasher load 7, top-loading clothes washer load 25, front-loading clothes washer load 15.
  • Busiest-hour examples: one shower and one hand dishwashing, 23 gallons; three showers, one shave, and one hand dishwashing, 65 gallons; four showers and one top-loading clothes washer load, 105 gallons. The middle one is the source's own example. Its uses add up to 65 gallons, and the source prints 66. The other two are this site's.
  • Fixture flows: hot water faucet 0.75 gallons per minute, shower head 2.5 gallons per minute. The flow examples add these up.
  • Temperatures: 50°F coming in and 120°F out for most uses, a 70°F rise; 140°F for a dishwasher with no heater of its own, a 90°F rise. The certified flow is at a 67°F rise.
  • Counts: a basic model meets an example where every one of its listed models does. The low end of its first-hour or flow range decides the result.
  • Tank check: the lowest first-hour figure must reach the busiest-hour demand. A shortfall rounds upward to whole gallons.
  • Tankless restatement: flow at the test's 67°F rise × 67 ÷ (hot water temperature − cold water temperature), at full heat. Display rounds half up to one decimal, or downward where rounding would exceed the advertised cap. Model counts use the unrounded estimate.
  • Flow cap: an advertised flow with no temperature stated, at or above the certified flow, caps the estimate. A flow advertised at a stated rise is a measurement, not a cap. Cold water less than 10°F below the hot water setting gets no estimate.
  • Household answer: the peak gallons, simultaneous flow, hot and cold water temperatures, and calculation time are stored as the reader's answer. Storage can be unavailable without preventing the calculation.

Replacement models

Household sizing: 2,573 basic-model figures, 1,752 tank checks, and 824 tankless flow blocks. An advertised flow caps 223 tankless estimates. Replacements cover 2,426 models in 20 groups. Listed dimensions cover 172 heights, 168 widths, and 168 depths.
Like for like
The same water heater type and sold-size group for tanks, or certified-flow group for tankless models.
Sort criteria
UEF highest first, low-end hot water output highest first, sold size smallest first for tanks, or flow smallest first for tankless models. Missing figures sort last. UEF compares within a draw pattern. With every pattern selected, rows group by pattern before UEF sorts within it.
Model window
Every model here was certified in the past year. An older model may be absent. Its label gives the type and size for the same group choice.
Dimensions
The product's listed height, width, and depth appear where present, in inches. No fit filter is inferred from absent measurements.

Figures print as the certification lists them, at fixed places. UEF has two decimals and flow has one. A brand-pair median is computed from the exact middle value or mean of the two middle values, then shown at two decimals. Gallons and percentages are whole numbers. A range runs from low to high.

Previous certification listings

Updates

The data was updated Oct 26, 2026. DOE CCMS includes current basic models with certification records submitted within the past year. A model absent from the current listing has not been re-published within that period. Absence does not establish withdrawal or discontinuation. Each absent model retains the date it was last listed.