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Rheem RTG 7.0 GPM Natural Gas Outdoor Review

Written from the listing's specs, not from our own use · How we rate

On paper, the Rheem RTG 7.0 GPM Natural Gas Outdoor gets the important things right: a 7 GPM maximum flow, outdoor mounting that skips the flue and a ±1 °F temperature hold. With a 15-year heat exchanger warranty as well, it suits one shower plus the kitchen in a typical family morning.

Price$819.08Price on Sep 30, 2026 · may have changed
Compare side by side ↗
Specifications
BrandRheem
CategoryGas tankless water heaters
FuelNatural gas
Stated mounting locationOutdoor
Stated maximum flow7 GPM
Stated gas input160,000 BTU/h
Flow at a stated rise7 GPM at a 35 °F rise
Temperature hold±1 °F, per the listing
Freeze protectionStated in the listing
Stated warranty15 years on the heat exchanger
ASINB0C827FQPG

Full listing title: Rheem RTG Series 7.0 GPM Natural Gas Tankless Water Heater Outdoor | 160,000 BTUs High Efficiency On Demand, Continuous Hot Water | Non-Condensing

Listing evidence
FuelNatural Gas Full listing title
Stated mounting locationOutdoor Full listing title
Stated maximum flow7.0 GPM Full listing title
Stated gas input160,000 BTUs Full listing title
Updated October 2026
Exact listing, ASIN B0C827FQPG
Rating from a published formula

Compared with its closest rivals

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

Compare side by side ↗

Rheem RTG 7.0 GPM Natural Gas Outdoor

Rheem RTG 7.0 GPM Natural Gas Outdoor

7.6Very good · out of 10$819.08 Price on Sep 30, 2026 · may have changed
  • Stated: 7 GPM · 160,000 BTU/h
  • Gas tankless water heaters
This product ↑
Westinghouse Natural Gas Outdoor

Westinghouse Natural Gas Outdoor

7.5Very good · out of 10$799.96 Price on Sep 30, 2026 · may have changed
  • Stated: 8.1 GPM · 180,000 BTU/h · 120 V
  • Gas tankless water heaters
See the review ↗
Konfino 190,000 BTU Natural Gas Outdoor

Konfino 190,000 BTU Natural Gas Outdoor

7.3Good · out of 10$529.79 Price on Sep 30, 2026 · may have changed
  • Stated: 8.1 GPM · 190,000 BTU/h · 120 V
  • Gas tankless water heaters
See the review ↗

Up to 7 GPM from a 160,000 BTU burner

That's the maximum flow the listing states, at a 35 °F rise. With January water coming in at 42 °F and a 105 °F shower, the rise is 63 °F and the real flow is lower; the maker's flow chart has that number. Counting 2 GPM per shower, as our calculator does, that's two showers and a kitchen tap, less when the water comes in cold.

What it has going for it

What changes in the morning shower rush

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.

±1 °F hold. The burner adjusts as the flow changes, so the shower stays where you set it when somebody opens the kitchen tap. On paper, at least: that is the seller's claim.

Mild winters or hard freezes?

Mild winters: the Rheem RTG 7.0 GPM Natural Gas Outdoor goes on an outside wall, which saves the vent pipe and keeps the closet free.

Hard freezes: the listing states freeze protection. It only works while the unit has power, so an outage on a frozen night is the risk to plan for; drain it if the power stays off.

Great for you if…

  • You run one shower and the kitchen tap at once, rarely more
  • There is no good vent route inside your house
  • A shower that suddenly runs cold drives you mad

Skip it if…

  • Your winters freeze hard and the outside wall has no power for freeze protection
  • You'd rather wait for buyer reviews: none are captured for this listing yet
  • You want the high-efficiency kind: the listing doesn't call it condensing

Gas, mounting and what's in the box

What the Rheem RTG 7.0 GPM Natural Gas Outdoor listing names:

  • Up to 7 GPM
  • 7 GPM at a 35 °F rise
  • 160,000 BTU/h input
  • Natural gas
  • Outdoor mounting
  • ±1 °F temperature hold claimed
  • Freeze protection named
  • CSA, ETL or UL mark named

Warranty & support: 15-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 Rheem RTG 7.0 GPM Natural Gas Outdoor if the maker asks, and read the install conditions: many tankless warranties need a licensed install and regular flushing.

The installation manual has the last word on venting, gas line and clearances; your installer reads it before you order.

Rheem RTG 7.0 GPM Natural Gas Outdoor, view 3

Price and cost per GPM of stated flow

$819.08 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 $117.01 (price ÷ stated GPM, our arithmetic). That puts it around the middle of the 32 outdoor tankless heaters we have a price and a stated flow for.

Outside mounting saves the vent pipe; the gas line, the water lines and a weatherproof outlet are still a separate bill.

The button opens the exact listing (ASIN B0C827FQPG), where today's price, stock and seller apply.

Rheem RTG 7.0 GPM Natural Gas Outdoor, view 4

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.

Our take

The verdict

Our favourite thing about the Rheem RTG 7.0 GPM Natural Gas Outdoor is a 7 GPM maximum flow, closely followed by outdoor mounting that skips the flue. No buyer reviews yet, so the Rheem RTG 7.0 GPM Natural Gas Outdoor has to win you over on paper. Honestly, the catch: the headline GPM is a mild-weather figure, so leave yourself margin for January. We'd pick it if you run one shower and the kitchen tap at once, rarely more; otherwise, put it next to the Rheem RTG 8.4 GPM Natural Gas Outdoor first.

Living with it

Install day

It goes on an outside wall, with gas, water and power run to it. Plan the gas line for 160,000 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. The listing's 7 GPM is at a 35 °F rise; a northern winter asks for about 63 °F. 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.

The one thing we'd check first

Before you order the Rheem RTG 7.0 GPM Natural Gas Outdoor, check your winter rise: it is rated 7 GPM at a 35 °F rise, and a northern winter asks for nearer 63 °F.

Before you buy

Your winter flow

Find your winter inlet temperature (your water utility or a thermometer at the cold tap in January), subtract it from 105 °F, and read the maker's flow chart at that rise. Our sizing guide shows how.

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

15 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 Rheem RTG 7.0 GPM Natural Gas Outdoor stacks up against the closest alternative, the Rheem RTG 8.4 GPM Natural Gas Outdoor.

CriterionRheem RTG 7.0 GPM Natural Gas OutdoorRheem RTG 8.4 GPM Natural Gas Outdoor
Our rating7.6/107.7/10
Max flow7 GPM8.4 GPM
Gas input160,000 BTU/h180,000 BTU/h

Pick the Rheem RTG 8.4 GPM Natural Gas Outdoor if you want our higher-rated option (7.7/10), with more flow (8.4 GPM) and a bigger burner (180,000 BTU/h).

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

8 / 10

Listing documentation

7 / 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 Rheem RTG 7.0 GPM Natural Gas 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 Rheem RTG 7.0 GPM Natural Gas Outdoor deliver?

The listing states a maximum flow of 7 GPM and a gas input of 160,000 BTU/h. 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 Rheem RTG 7.0 GPM Natural Gas 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 Rheem RTG 7.0 GPM Natural Gas Outdoor?

Its listing states up to 7 GPM, outdoor mounting that skips the flue, temperature held within ±1 °F and a 15-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 Rheem RTG 7.0 GPM Natural Gas Outdoor?

Your winter flow: find your winter inlet temperature (your water utility or a thermometer at the cold tap in January), subtract it from 105 °F, and read the maker's flow chart at that rise. Our sizing guide shows how. 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: 15 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 Rheem RTG 7.0 GPM Natural Gas 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 Rheem RTG 7.0 GPM Natural Gas Outdoor yourselves?

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