Every other brand page on this site reviews a company that actually designs and builds its own tankless units. Westinghouse doesn’t — it exited home-appliance manufacturing years ago and now licenses its name across categories, the same way it licenses lighting, tools, and TVs to unrelated manufacturers. For hot water specifically, that license has gone to two different companies for two different product tiers, which means “Westinghouse tankless water heater” isn’t one product line with one engineering team behind it — it’s a brand name stamped on gear from two separate factories.
Our top picks at a glance
| Model | Best for | Power | Flow | Price |
|---|---|---|---|---|
| Apolo Mini 3.5kW | Single sink / point-of-use | 120V / 30A | 0.68 GPM | ~$169.99 |
| Apolo Performance 18kW | Small home, 2-4 fixtures | 240V | 4.2 GPM | ~$339-$349 |
| Apolo 27kW Whole House | Larger home | 240V | ~5.4 GPM est. | ~$459-$580 |
Prices per current retailer listings: Apolo Mini 3.5kW $169.99 at Tractor Supply (was $229.99); Apolo Performance 18kW $339-$349 depending on retailer; Apolo 27kW Whole House $459 at one retailer vs. $579.99 at another — a real spread worth a quick check before you buy. Amazon pricing moves independently of these figures.
By the numbers
- Two separate license deals — trade-press coverage (License Global, April 2018; Licensing International) confirms HTP holds the North American Westinghouse license for gas and electric hot-water systems aimed at the installer/commercial channel, while the consumer Apolo electric line sold at Tractor Supply and Lowe’s lists Fogatti — an RV appliance OEM founded in 2003 — as the manufacturer on at least one retailer listing. Same brand name, two unrelated factories.
- 1,200+ verified reviews, 4.5-star average — the Apolo Performance 18kW’s review count at one major retailer, the most-reviewed model in the consumer line, per retailer-listing data.
- 11 GPM at a 199,000 BTU input — the WGRGHNG199 gas condensing unit’s rated output at a 35°F rise, dropping to 8.5 GPM at a 45°F rise per its own spec sheet — the same climate-dependent GPM story that applies across every brand on this site, gas or electric.
1. Apolo Mini 3.5kW — Best Point-of-Use
Westinghouse Apolo Mini 3.5kW Electric Tankless Water Heater
- The smallest model in the Apolo line, built for one fixture — not rated for whole-body bathing, per its own spec sheet.
- Plugs into a dedicated 120V/30A circuit rather than the 240V double-pole breaker the larger Apolo models need, which keeps the electrical work closer to a standard outlet swap.
- Tractor Supply currently lists it at $169.99, down from $229.99 — check that markdown against current Amazon pricing before ordering.
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A 3.5kW unit like the Apolo Mini is the right size for a single far-flung fixture — a workshop sink, a bar, a detached laundry tub — not a whole house. For a side-by-side against other 120V point-of-use brands that skip a breaker install entirely, see our best point-of-use water heater roundup.
2. Apolo Performance 18kW — Best for Small Homes
Westinghouse Apolo Performance 18kW Electric Tankless Water Heater
- The most-reviewed model in the Apolo line at over 1,200 verified reviews and a 4.5-star average at one major retailer, per that listing's own review data.
- Owner reports flag the real climate catch: the rated 4.2 GPM flow holds up at moderate incoming water temperatures but drops when groundwater runs around 40°F in northern winters — the same fixed-kW-ceiling tradeoff every electric tankless brand on this site runs into.
- Priced around $339-$349 across current listings; confirm the exact figure at checkout since retailer pricing on this model has moved within that range.
The 18kW Apolo Performance is where this line starts covering genuine small-home demand rather than a single fixture. See our tankless water heater sizing guide for how to size GPM against your actual winter groundwater temperature rather than the headline flow-rate number.
3. Apolo 27kW Whole House — Best for Larger Homes
Westinghouse Apolo 27kW Whole House Electric Tankless Water Heater
- The largest electric model in the consumer Apolo line, positioned for whole-house demand rather than a single small home's 2-4 fixtures.
- Pricing varies more than the smaller models — one retailer lists it at $459, another at $579.99 — a bigger spread than the 18kW model's range, so check more than one listing before buying.
- Still a fixed-kW electric unit: the same winter groundwater derate that applies to the 18kW model applies here too, just at a higher ceiling.
For a true whole-house comparison against gas-fired alternatives that don’t share electric’s cold-weather flow derate, see our best whole-house tankless water heater roundup, or our best electric tankless water heater guide for how the 27kW stacks up against EcoSmart and Eemax at the same output tier.
How to choose a Westinghouse tankless water heater
- One sink or a detached fixture: the Apolo Mini 3.5kW — a 120V plug, not a 240V breaker install.
- Small home, 2-4 fixtures: the Apolo Performance 18kW — the most-reviewed model, but check the real cold-groundwater flow derate against your region.
- Larger home, whole-house electric: the Apolo 27kW Whole House — budget for a real 240V circuit and shop more than one listing given the wider price spread.
- Installer-grade gas condensing: the WGRGHNG199 and its propane sibling WGRTLP199 target the same Pro channel as Rinnai’s and Navien’s commercial-adjacent lines — a different buyer than anyone shopping Tractor Supply or Amazon for the electric Apolo line.
The bottom line
Westinghouse’s tankless lineup is a genuine two-manufacturer situation hiding behind one familiar brand name: HTP holds the license for the gas condensing commercial-grade units sold through Home Depot’s Pro channel, and Fogatti — an unrelated RV appliance OEM — builds the consumer electric Apolo line sold at Tractor Supply, Lowe’s, and Home Depot’s retail shelf. For most home shoppers, the Apolo Performance 18kW is the practical small-home pick once you size it against your winter groundwater temperature rather than its headline 4.2 GPM; the Apolo Mini 3.5kW covers a single fixture, and the Apolo 27kW Whole House is the largest electric tier, worth comparing across more than one retailer given the real price spread between listings. For the full brand field this fits into, see our best tankless water heater guide, or our best electric tankless water heater roundup for how it stacks up against EcoSmart, Eemax, and Atmor.
Check the Westinghouse Apolo Performance 18kW price on Amazon →