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Westinghouse 120,000 BTU Propane Outdoor Review

Name: Westinghouse 120,000 BTU Propane Outdoor
Brand: Westinghouse
SKU: B0F66H2K7G

7.6Very good · out of 10Rated from the listing's specs, no buyer reviews yet

Written from the listing and 12 buyer reviews, not from our own use · How we rate

The Westinghouse 120,000 BTU Propane Outdoor packs up to 5.1 GPM, a 0.81 UEF rating and an outside-wall install with no vent run into one outdoor tankless heater. Rated 7.6/10, it suits an outside wall instead of a flue through the roof.

Price$799.99Price on Sep 30, 2026 · may have changed

Check the price on Amazon ↗Affiliate link · price and stock on Amazon

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Specifications

Brand	Westinghouse
Category	Gas tankless water heaters
Fuel	Propane
Stated mounting location	Outdoor
Stated maximum flow	5.1 GPM
Stated gas input	120,000 BTU/h
Stated voltage	120 V
Stated efficiency	0.81 UEF
Temperature range	95 to 158 °F
Temperature hold	±1 °F, per the listing
Freeze protection	Stated in the listing
Stated warranty	5 years on the heat exchanger
Buyer reviews	12 · 4.8/5
ASIN	B0F66H2K7G

Full listing title: Westinghouse Tankless Water Heater Propane Outdoor, 5.1 GPM 120,000BTU, CSA

Listing evidence

Fuel	Propane Full listing title
Stated mounting location	Outdoor Full listing title
Stated maximum flow	5.1 GPM Full listing title
Stated gas input	120,000BTU Full listing title
Stated voltage	120V Listing text

Updated October 2026

Exact listing, ASIN B0F66H2K7G

Rating from a published formula

Compared with its closest rivals

Two gas tankless heaters on propane too, with about the same flow, closest to it on our rating, each with a dated price.

Compare side by side ↗

Westinghouse 120,000 BTU Propane Outdoor

7.6Very good · out of 10$799.99 Price on Sep 30, 2026 · may have changed

Stated: 5.1 GPM · 120,000 BTU/h · 120 V
12 buyer reviews
Gas tankless water heaters

This product ↑

Ranein 130,000 BTU Propane Outdoor

7.5Very good · out of 10$579 Price on Sep 30, 2026 · may have changed

Stated: 5.3 GPM · 130,000 BTU/h
710 buyer reviews
Gas tankless water heaters

See the review ↗

Rinnai RE160eP Non-Condensing

7.1Good · out of 10$893.34 Price on Sep 30, 2026 · may have changed

Stated: 6.1 GPM
5 buyer reviews
Gas tankless water heaters

See the review ↗

Up to 5.1 GPM from a 120,000 BTU burner

That's the maximum flow the listing states, and headline flows are usually quoted at a mild temperature rise. In January the water comes in nearer 42 °F, so a 105 °F shower needs a 63 °F rise and the unit gives you less; the flow chart in the manual shows how much less. At 2 GPM a shower (our calculator's figure), the headline means one shower and a sink at a time, maybe two showers where the water comes in warm.

What it has going for it

What changes in the morning shower rush

0.81 UEF. Uniform Energy Factor is the federal efficiency label: the higher it is, the less gas or power goes up the vent instead of into your shower.

Mounts outside. No vent pipe through the roof or the rim joist: it hangs on an outside wall and breathes on its own. The listing states freeze protection, which typically needs power at the wall to work.

Mild winters or hard freezes?

Mild winters: an outside wall is the easy spot. No vent through the roof or the rim joist, no combustion air to plan inside the house.

Hard freezes: the listing names freeze protection, which needs power at the wall. Plan for the night the power goes out and the thermometer drops: draining it is the fallback.

Great for you if…

There is no good vent route inside your house
A shower that suddenly runs cold drives you mad
You want a long warranty: 5 years are stated

Skip it if…

Your winters freeze hard and the outside wall has no power for freeze protection
You want a long review record: only 12 buyer reviews so far
You want the high-efficiency kind: the listing doesn't call it condensing

What Westinghouse promises

The seller states, word for word, in the Westinghouse 120,000 BTU Propane Outdoor listing:

Supports 2–4 fixtures simultaneously for showers, kitchen sinks, dishwashers, and laundry.
Comes standard with a wired digital controller for convenient temperature adjustment from multiple points around the house, with an adjustable range of 95°F–158°F for precise on-demand heating.
The unit achieves UEF above 0.81.
If temperatures drop below 32°F (0°C) without continuous power, drain the unit fully to prevent freeze damage.
The built-in self-diagnosis system displays error codes on the controller when abnormal operation occurs, enabling quick troubleshooting and simplified routine maintenance.

The seller's claims, quoted as written; we haven't measured any of it. The flow at your winter rise is in the maker's chart, not in the bullet points.

Westinghouse 120,000 BTU Propane Outdoor, view 3

Gas, mounting and what's in the box

What the Westinghouse 120,000 BTU Propane Outdoor listing names:

Up to 5.1 GPM
120,000 BTU/h input
Propane
Outdoor mounting
0.81 UEF
±1 °F temperature hold claimed
95 to 158 °F setpoint
Freeze protection named
CSA, ETL or UL mark named

Warranty & support: 5-year warranty on the heat exchanger, as stated in the listing · CSA, ETL or UL certification named in the listing.

That is the maker's promise, not ours. Keep the invoice, register the Westinghouse 120,000 BTU Propane Outdoor if the maker asks, and read the install conditions: many tankless warranties need a licensed install and regular flushing.

For the Westinghouse 120,000 BTU Propane Outdoor, the installation manual settles the venting, the gas line and the clearances.

Westinghouse 120,000 BTU Propane Outdoor, view 4

Price and cost per GPM of stated flow

$799.99 Price on Sep 30, 2026 · may have changed

At the price on Sep 30, 2026, each GPM of stated maximum flow works out at about $156.86 (price ÷ stated GPM, our arithmetic). That puts it in the pricier third of the 32 outdoor tankless heaters we have a price and a stated flow for.

No vent run to pay for, but the gas line, the water lines to the outside wall and an outlet for the freeze protection still come on top.

The button opens the exact listing (ASIN B0F66H2K7G), where today's price, stock and seller apply.

Westinghouse 120,000 BTU Propane Outdoor, view 5

A better fit for your house?

Two showers and the dishwasher at once? The A. O. Smith 10 GPM Natural Gas Outdoor (8.0/10) states up to 10 GPM.

Hard freezes where you live? The ThermoMate CZ422LP Propane Indoor (7.8/10) is an indoor unit, out of the frost.

Want the high-efficiency kind? The ThermoMate Condensing Propane (7.6/10) is a condensing unit rated 0.86 UEF, per its listing.

Our take

The verdict

The Westinghouse 120,000 BTU Propane Outdoor earns its place with up to 5.1 GPM and a 0.81 UEF rating. Only 12 buyers have rated it so far (4.8/5), so treat the score as an early read. The catch with this Westinghouse outdoor tankless heater: the headline GPM is a mild-weather figure, so leave yourself margin for January. We'd pick it if there is no good vent route inside your house; otherwise, put it next to the Rheem RTG 7.0 GPM Natural Gas Outdoor first.

Check the price on Amazon ↗Affiliate link · price and stock on AmazonAll gas tankless water heaters →

Living with it

Install day

It goes on an outside wall, with gas, water and power run to it. Plan the gas line for 120,000 BTU/h; a licensed pro handles it, and often a permit.

The first shower

Hot water arrives after the cold already in the pipes, then stays (within ±1 °F, per the listing). A trickle from a bathroom tap may not light the burner; open it a bit more.

The first winter

January water comes in colder, so the same unit gives fewer GPM. Stagger the showers if you sized it tight.

Once a year

Flush the heat exchanger with a pump and a descaler (the service valves make it an hour's job), and clear leaves and wasp nests from the cabinet vents. Our flushing and descaling guide has the checklist.

What buyers say

Buyers give it 4.8/5, an excellent record, well above our ranked picks' 4.3 average. Only 12 reviews so far, and our formula damps averages built on fewer than 50.

The numbers

Buyer rating: 4.8/5
Reviews: 12
Ranked picks' average: 4.3/5

The one thing we'd check first

Before you order the Westinghouse 120,000 BTU Propane Outdoor, check your gas line: 120,000 BTU/h is a lot of gas at once, so ask your plumber whether the existing line can feed it.

Before you buy

Your winter flow

5.1 GPM is the headline. In a northern January the water comes in near 42 °F, so a 105 °F shower needs a 63 °F rise and the real flow drops. Our flow-rate calculator runs the numbers for your house.

The outside wall

Pick a wall away from windows and doors, with power for the controls and the freeze protection the listing mentions. Our indoor vs outdoor guide compares the two installs.

The warranty terms

5 years are stated on the heat exchanger. Read what it requires: a licensed install, the gas type and regular flushing are the usual conditions.

Flushing

Hard water scales the heat exchanger. Service valves on the water lines turn the yearly flush into an hour with a bucket and a pump; our flushing and descaling guide shows the routine.

How it compares

How the Westinghouse 120,000 BTU Propane Outdoor stacks up against the closest alternative, the Rheem RTG 7.0 GPM Natural Gas Outdoor.

Criterion	Westinghouse 120,000 BTU Propane Outdoor	Rheem RTG 7.0 GPM Natural Gas Outdoor
Our rating	7.6/10	7.6/10
Max flow	5.1 GPM	7 GPM
Gas input	120,000 BTU/h	160,000 BTU/h
Efficiency	0.81 UEF	Not stated
Warranty	5 years (heat exchanger)	15 years (heat exchanger)
Buyer reviews	12 · 4.8/5	None captured

Both score 7.6/10. The Rheem RTG 7.0 GPM Natural Gas Outdoor adds more flow (7 GPM) and a bigger burner (160,000 BTU/h), while the Westinghouse 120,000 BTU Propane Outdoor brings a stated 0.81 UEF.

Compare side by side ↗See the Rheem RTG 7.0 GPM Natural Gas Outdoor review →

The score in detail

How we rated it

Spec-based rating on a 4.5–8.5 scale: 4.5 + average of the 4 criteria × 0.4. Capped at 8.5 because no customer evidence is included.

Key specifications

8 / 10

Build, warranty & certifications

7 / 10

Listing documentation

8 / 10

Fit & compatibility

8 / 10

This product has no captured buyer-review record yet, so its rating comes from the documented listing alone: four criteria scored out of 10 (key specifications; build, warranty and certifications; listing documentation; fit and compatibility), placed on a 4.5–8.5 scale. Read the full methodology.

Read the methodology →

Frequently asked questions

Is the Westinghouse 120,000 BTU Propane Outdoor any good?

We rate it 7.6/10 (very good). The rating comes from its documented listing alone, as no customer-review record is captured yet.

How much hot water can the Westinghouse 120,000 BTU Propane Outdoor deliver?

The listing states a maximum flow of 5.1 GPM and a gas input of 120,000 BTU/h on 120 V. The headline flow is a mild-weather number: with cold winter water coming in, the same unit gives you less. Read the maker's flow chart at your winter rise, or let our flow-rate calculator do the sums.

Can the Westinghouse 120,000 BTU Propane Outdoor be installed indoors?

The listing says outdoor mounting. It only goes inside if the maker lists that exact model for indoor use, with the venting it specifies; a licensed gas installer confirms the spot under your local code.

What do you get with the Westinghouse 120,000 BTU Propane Outdoor?

Its listing states up to 5.1 GPM, a 0.81 UEF rating, outdoor mounting that skips the flue, temperature held within ±1 °F and a 5-year heat exchanger warranty. These are the seller's figures, not our measurements: how steady the temperature is in your shower and how it copes with your winter water can't be read from a listing.

What should I check before ordering the Westinghouse 120,000 BTU Propane Outdoor?

Your winter flow: 5.1 GPM is the headline. In a northern January the water comes in near 42 °F, so a 105 °F shower needs a 63 °F rise and the real flow drops. Our flow-rate calculator runs the numbers for your house. The outside wall: pick a wall away from windows and doors, with power for the controls and the freeze protection the listing mentions. Our indoor vs outdoor guide compares the two installs. The warranty terms: 5 years are stated on the heat exchanger. Read what it requires: a licensed install, the gas type and regular flushing are the usual conditions. Flushing: hard water scales the heat exchanger. Service valves on the water lines turn the yearly flush into an hour with a bucket and a pump; our flushing and descaling guide shows the routine.

Where can I buy the Westinghouse 120,000 BTU Propane Outdoor?

We link to the exact listing on Amazon, where today's price, stock and seller apply. It is an affiliate link, and it has no effect on the rating.

Have you used the Westinghouse 120,000 BTU Propane Outdoor yourselves?

No, we haven't used it ourselves. Everything on this page comes from its listing and 12 buyer reviews, read line by line and weighed with our published formula.

Gas tankless water heaters ↗All Westinghouse products Comparison tool All product reviews