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Written from the listing's specs, not from our own use · How we rate
The Noritz NR98-OD Natural Gas Outdoor ticks most of the boxes we care about: up to 7.5 GPM and an outside-wall install with no vent run. A good match for a two-bathroom house with one shower running at a time, rated 6.8/10 on its documented specs.
| Brand | Noritz |
|---|---|
| Category | Gas tankless water heaters |
| Fuel | Natural gas |
| Stated mounting location | Outdoor |
| Stated maximum flow | 7.5 GPM |
| Stated gas input | 199,000 BTU/h |
| ASIN | B003UHUXCA |
Full listing title: Noritz NR98-OD NG Outdoor Tankless Natural Gas Water Heater, 7.5 GPM
| Fuel | Natural GasFull listing title |
|---|---|
| Stated mounting location | OutdoorFull listing title |
| Stated maximum flow | 7.5 GPMFull listing title |
| Stated gas input | 199,000 BTUListing text |
Rated from the listing's specs, no buyer reviews yet
What it's made for: a two-bathroom house with one shower running at a time.
Two gas tankless heaters on natural gas too, with about the same flow, closest to it on our rating, each with a dated price.
That's the maximum flow the listing states, and headline flows are usually quoted at a mild temperature rise. A cold January asks for a 63 °F rise (42 °F in, 105 °F out), and at that rise every tankless gives less than its headline; the maker's chart says how much. 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
Mounts outside. No vent pipe through the roof or the rim joist: it hangs on an outside wall and breathes on its own. In a cold climate, ask what keeps it from freezing.
Mild winters: the Noritz NR98-OD Natural Gas Outdoor goes on an outside wall, which saves the vent pipe and keeps the closet free.
Hard freezes: the listing names no freeze protection, so ask the seller what keeps it from bursting before it goes on a north wall.
What the Noritz NR98-OD Natural Gas Outdoor listing names:
The installation manual has the last word on venting, gas line and clearances; your installer reads it before you order.
At the price on Sep 30, 2026, each GPM of stated maximum flow works out at about $271.46 (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 B003UHUXCA), where today's price, stock and seller apply.
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 Ranein 190,000 BTU Natural Gas Indoor (7.9/10) is an indoor unit, out of the frost.
Want the high-efficiency kind? The Rheem RTGH 8.4 GPM Natural Gas Indoor (7.3/10) is a condensing unit, per its listing.
Our take
We like the Noritz NR98-OD Natural Gas Outdoor for up to 7.5 GPM and an outside-wall install with no vent run. No buyer has reviewed it yet, so our 6.8/10 comes from the spec sheet alone. The catch with this Noritz outdoor tankless heater: no stated temperature hold, while most picks here claim ±1 °F. We'd pick it if you run one shower and the kitchen tap at once, rarely more; otherwise, put it next to the CAMPLUX 150,000 BTU Propane Outdoor first.
It goes on an outside wall, with gas, water and power run to it. Plan the gas line for 199,000 BTU/h; a licensed pro handles it, and often a permit.
Hot water arrives after the cold already in the pipes, then stays. A trickle from a bathroom tap may not light the burner; open it a bit more.
January water comes in colder, so the same unit gives fewer GPM. Stagger the showers if you sized it tight.
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.
Before you order the Noritz NR98-OD Natural Gas Outdoor, check your gas line: 199,000 BTU/h is a lot of gas at once, so ask your plumber whether the existing line can feed it.
7.5 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.
Pick a wall away from windows and doors, with power for the controls. Our indoor vs outdoor guide compares the two installs.
Read what it requires: a licensed install, the gas type and regular flushing are the usual conditions.
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 the Noritz NR98-OD Natural Gas Outdoor stacks up against the closest alternative, the CAMPLUX 150,000 BTU Propane Outdoor.
| Criterion | Noritz NR98-OD Natural Gas Outdoor | CAMPLUX 150,000 BTU Propane Outdoor |
|---|---|---|
| Our rating | 6.8/10 | 6.8/10 |
| Max flow | 7.5 GPM | 6.4 GPM |
| Gas input | 199,000 BTU/h | 150,000 BTU/h |
| Temperature hold | Not stated | ±1 °F stated |
| Buyer reviews | None captured | 76 · 4.3/5 |
Both score 6.8/10. The CAMPLUX 150,000 BTU Propane Outdoor adds a stated ±1 °F hold, while the Noritz NR98-OD Natural Gas Outdoor brings more flow (7.5 GPM) and a bigger burner (199,000 BTU/h).
We rate it 6.8/10 (good). The rating comes from its documented listing alone, as no customer-review record is captured yet.
The listing states a maximum flow of 7.5 GPM and a gas input of 199,000 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.
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.
Its listing states up to 7.5 GPM and outdoor mounting that skips the flue. 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.
Your winter flow: 7.5 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. Our indoor vs outdoor guide compares the two installs. The warranty terms: 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.
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.
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.