Rheem RTG-84DVLN-3 180,000 BTU Natural Gas Tankless Water Heater

What it delivers

The Rheem RTG-84DVLN-3 180,000 BTU Natural Gas Tankless Water Heater is a non-condensing gas tankless with a 180,000 BTU/h burner and a stated maximum flow of 8.4 GPM.

Flow depends on how cold the incoming water is. Our estimate from its input: 6.2 GPM at a 45°F rise, falling to 4.0 GPM at 70°F, which is 1 shower at 2 GPM on a cold-climate winter day. Check it against your own fixtures.

Gas load at full fire: about 174 cubic feet of natural gas an hour. An older half-inch line that already feeds a furnace often can't spare that, so have a gas fitter check the pipe size and run.

Its exhaust runs hot, so the vent must be the material its manual lists, usually stainless; budget for the vent kit.

The listing describes its venting as: direct vent.

Also on the listing: material: Stainless Steel; model: RTG-84DVLN-3; warranty: 1 Year Labor, 15 Year Heat Exchanger, 5 Year Parts.

The listing gives dimensions of 13.5 in (W) x 24.2 in (H), a weight of 46.5 lb and display in the box.

Warranty, per the listing: 1 Year Labor, 15 Year Heat Exchanger, 5 Year Parts.

Right unit for this house?

Install it when

One shower at a time in cold climates
Replacing a gas tank heater

Look at another unit when

More than 1 winter shower at once
Homes without a gas line

Strengths and trade-offs

Strengths

180,000 BTU/h input
Up to 8.4 GPM

Trade-offs

Gas pipe sizing to confirm
Stainless venting costs more
Annual flushing on hard water

Install limits

Figures are the maker's or seller's own. Flow at a rise is our estimate from the input; gas, venting and electrical work needs a licensed professional.

Rated performance

Every figure below comes from the source shown in brackets. Where the maker doesn't state something, we say so instead of estimating.

Model number	RTG-84DVLN-3	Retailer
Dimensions (seller)	13.5"W x 24.2"H	Retailer
Voltage	120 V	Retailer
Max flow (maker)	8.4 GPM	Retailer
Input (maker)	180,000 BTU/h	Retailer
Product weight	46.5 lb	Retailer
Material	Stainless Steel	Retailer
Warranty	1 Year Labor, 15 Year Heat Exchanger, 5 Year Parts	Retailer
Fuel	Natural Gas	Retailer
Venting	direct vent	Retailer
Condensing	Non-Condensing	Retailer

Rival units at this flow

MIZUDO HW180A0W-NG 180,000 BTU Natural Gas Tankless Water Heater180,000 BTU/h, up to 7.9 GPM.

Rinnai RE180eN Natural Gas Tankless Water Heater180,000 BTU/h, up to 8.5 GPM.

Rinnai RE180iN Natural Gas Tankless Water Heater180,000 BTU/h, up to 8.5 GPM.

More gas tankless water heaters rated for similar demand

Full gas tankless water heaters spec grid · Every Rheem unit in the catalog

Final verdict

A practical non-condensing gas tankless for one shower at a time in cold climates.

Buy this unit

Our links open this exact model's product page. Prices and stock change; check what's included before you order.

Prices change often; the button shows today's price.

Check price on Amazon

Each button opens this exact model. We may earn a commission on tracked links; it never changes what we publish. Disclosure

Questions buyers ask

Is the Rheem RTG-84DVLN-3 180,000 BTU Natural Gas Tankless Water Heater big enough for two showers?

From its 180,000 BTU/h input we estimate about 6.2 GPM at a 45°F rise and 4.0 GPM at a 70°F rise, so 3 two-GPM showers with mild inlet water and 1 in a cold winter. The maker's flow chart for this model is the final word.

What size gas line does the Rheem RTG-84DVLN-3 180,000 BTU Natural Gas Tankless Water Heater need?

At full fire it uses about 174 cubic feet of natural gas an hour. The pipe size depends on the length of the run and every other gas appliance on it; the maker's manual and a licensed gas fitter decide it.