Updated 2026-10-23
There is no single best water heater brand. All five makers below sell water heaters into US homes, but not the same types, so the useful questions are narrower: which of them makes the type you need, who is allowed to sell and install it, and what the warranty paper covers once the tank leaks. Settle tank vs tankless first; then pick the brand inside the type.
Best for a pro-installed tank
Bradford White
Sold only through plumbing professionals, and its tank warranty follows the heater to the next owner as long as it stays where it was installed.
Best for tankless with recirculation
Navien NPE-A2
A recirculation pump and buffer tank inside the unit, PVC venting, and a heat exchanger term that drops from fifteen years to five if the loop runs uncontrolled.
Highest heat pump efficiency read
Rheem ProTerra
The hybrid ProTerra listing carries the highest UEF of the heat pump listings read for this page, ahead of Navien, Rinnai and A. O. Smith.
What each maker lists for US homes on its own site, read on 2026-10-23. A dash means the maker's residential menu does not list that type.
| Factor | A. O. Smith | Bradford White | Rheem | Rinnai | Navien |
|---|---|---|---|---|---|
| Gas tank | ProLine tiers | Yes | Yes | — | — |
| Electric tank | Yes | Yes | Professional Classic | — | — |
| Gas tankless | Adapt, condensing and non-condensing | Infiniti GR, GS, L, K | Condensing and non-condensing | Condensing and non-condensing | Condensing and non-condensing |
| Heat pump, top UEF listed | Voltex MAX, 3.84 UEF | AeroTherm, ENERGY STAR | ProTerra, 4.07 UEF | REHP, 4.0 UEF | NWP500, 4.05 UEF |
| Tank warranty, as printed | 6, 8 or 10 yr | 1, 6, 8 or 10 yr | Serial lookup | Not printed | Not printed |
| How the maker says to buy | Contractor locator | Plumbing pros only | Find a Rheem Pro | A Rinnai PRO | Authorized distributor |
The brand is not the warranty
Each card says what the maker builds for a house, how it reaches the job, and the one thing a plumber should know before quoting it. None of them is ranked above another here: the verdict rows at the top name the criterion each pick won on.
Gas and electric tanks, gas and electric tankless, hybrid heat pump, split-system heat pump, combi boiler and solar, all on one residential menu. The gas tanks come in ProLine, ProLine Master and ProLine XE tiers, at 6, 8 or 10 years of tank cover.
The company also owns State, American, Reliance, Lochinvar and Takagi, so a heater with a different badge can come from the same group. Its residential warranty stays with the original buyer and does not transfer with the house.
Gas, electric, heat pump, tankless and indirect heaters, made in Middleville, Michigan, and, in the company's words, “available exclusively through plumbing professionals”. A homeowner gets one through a plumber, not a store aisle.
The tank term is written into the model number: a T6 is six years, a T10 ten. Parts carry 6 years, and the cover passes to the next owner while the heater stays where it was installed.
Tanks, gas and electric tankless, point-of-use and indirect heaters, plus the ProTerra heat pump line. Rheem lists its hybrid ProTerra models in 40 to 80 gal at up to 4.07 UEF, and its Professional Classic electric tanks at 0.90 to 0.94 UEF.
Ruud is the sister brand. Rheem prints no warranty years on its warranty page: coverage is read against the serial number, so ask for the term in writing with the quote.
A tankless maker first. Condensing models in the RX, RXP, RUS and RUCS series, non-condensing in RE, REP and V, and the REHP heat pump at up to 4.0 UEF. Rinnai sends buyers to a Rinnai PRO.
Labour cover is one year, or five if the heater is registered within 90 days of purchase. The heat exchanger and parts terms sit in the installation and owner's guide, not on the warranty page.
Condensing and non-condensing tankless, combi-boilers and the NWP500 heat pump at up to 4.05 UEF. Navien sells through authorized distributors and says installation must be done by a licensed professional.
The warranty excludes a non-licensed installer and scale build-up, so on hard water the treatment is part of the job, not an extra.
On a gas tankless the brand question is really three questions: does the unit condense, can it recirculate without a separate pump, and will the existing gas line and vent route serve it. The makers publish the first two; the third is the job, and the tankless water heater cost guide shows where that money goes.
| Maker | Condensing line | Top UEF printed | Built-in recirculation |
|---|---|---|---|
| Rinnai | SENSEI RX, RXP, RUS, RUCS | 0.98 | RXP and REP models, pump built in |
| Navien | NPE-A2, NPE-S2 | 0.95 | NPE-A2: pump and buffer tank inside |
| Bradford White | Infiniti GR, GS, L, K (condensing not stated) | Not printed | GR and L models |
| A. O. Smith | Adapt+ and Adapt SC | 0.95 | Not shown on the listing |
| Rheem | IKONIC, RTGH | 0.96 | IKONIC with pump; RTG-R (non-condensing) |
Navien prints its installation limits on the product page. It rates the NPE-A2 for 2" PVC venting up to 75 ft and a 1/2" gas line up to 24 ft, the two runs that decide whether a tank swap can stay on the existing gas stub and how far the new vent may go. Check the gas run on the gas pipe size calculator before taking the maker's figure as yours. Rinnai prints the higher efficiency, and Bradford White quotes a 15-year warranty on its Infiniti line with an asterisk whose terms the page does not show.
Every maker on this page lists a heat pump tank. The printed efficiency is close across them: Rheem's ProTerra hybrid up to 4.07, Navien's NWP500 up to 4.05, Rinnai's REHP up to 4.0 and A. O. Smith's Voltex MAX up to 3.84 UEF. Bradford White lists its AeroTherm as ENERGY STAR certified without a UEF on the page. A gap that small decides less than the room the unit goes in, the drain for its condensate and the circuit it needs, so size it first in the water heater sizing calculator.
The years on the box are the headline. The paper behind them decides whether a leaking tank in year five is a free heater, a free heater plus your labour bill, or nothing. Two tank warranties read in full show how far apart the terms sit.
| Term | Bradford White | A. O. Smith |
|---|---|---|
| Tank years | 1, 6, 8 or 10, from the model number | 6, 8 or 10, from the warranty code |
| Parts years | 6 | Same as the tank term |
| Who is covered | First buyer and later owners, while it stays installed where it was | Original buyer only, not transferable |
| Outside a single-family home | 1 yr tank and parts (3 yr tank on a 10-year model) | 1 yr |
| Labour to remove and refit | Not covered | Owner pays |
| Closed system, no expansion control | Excluded | Excluded |
| Anode rods | Consumable, excluded | Consumable, excluded |
Two exclusions appear in both. A heater on a closed system with no way to absorb thermal expansion is outside the cover, which is one more reason the expansion tank belongs on the quote. And neither maker pays a plumber to pull the old tank and set the new one, so the labour line on a water heater replacement is the homeowner's even inside the term. The anode is a service part in both papers; the anode rod guide covers when to check it.
Tankless terms depend on the loop
Before you sign for a water heater