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Written from the listing and 25 buyer reviews, not from our own use · How we rate
The Takagi T-H3S-DV-N Condensing Indoor packs an 8 GPM maximum flow and condensing efficiency into one indoor gas tankless heater. It earned a spot in our top 5 high-efficiency condensing tankless water heaters, and it's built for a two-bathroom house with one shower running at a time.
| Brand | Takagi |
|---|---|
| Category | Gas tankless water heaters |
| Fuel | Natural gas |
| Stated mounting location | Indoor |
| Stated maximum flow | 8 GPM |
| Condensing design | Stated in the listing title |
| Buyer reviews | 25 · 4.4/5 |
| ASIN | B00DDPZ4F0 |
Full listing title: Takagi T-H3S-DV-N Condensing High Efficiency Natural Gas Indoor Tankless Water Heater, 8-Gallon Per Minute
| Fuel | Natural GasFull listing title |
|---|---|
| Stated mounting location | IndoorFull listing title |
| Stated maximum flow | 8-Gallon Per MinuteFull listing title |
| Condensing design | CondensingFull listing title |
The two picks next to it in our high-efficiency condensing tankless water heaters ranking, with their rating and a dated price.
That's the maximum flow the listing states, and headline flows are usually quoted at a mild temperature 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. At 2 GPM a shower (our calculator's figure), the headline means two showers and a kitchen tap, less when the water comes in cold.
Why it made our list
Condensing. A second heat exchanger pulls heat out of the exhaust before it leaves, so more of the gas you pay for ends up in the water. The exhaust runs cool enough for plastic vent pipe, and the condensate needs a drain.
Two at once: up to 8 GPM, and our calculator counts a shower at 2 GPM, so that's two showers and a tap on paper. How much of it is left in January is on the maker's flow chart, at a 63 °F rise.
One at a time: a smaller unit covers that for less money.
What the Takagi T-H3S-DV-N Condensing Indoor listing names:
For the Takagi T-H3S-DV-N Condensing Indoor, the installation manual settles the venting, the gas line and the clearances.
We have no recent price on file for this listing, so we don't print an old one.
The heater is often the smaller half of the bill: the venting, a gas line that may need upsizing and a licensed installer's day come on top.
The button opens the exact listing (ASIN B00DDPZ4F0), where today's price, stock and seller apply.
Two showers and the dishwasher at once? The MIZUDO 199,000 BTU Natural Gas Indoor (9.2/10) states up to 10.3 GPM.
No easy route for a vent pipe? The Rheem RTG 8.4 GPM Natural Gas Outdoor (7.7/10) mounts on an outside wall, per its listing.
On propane, not natural gas? The Rheem RTGH 9.5 GPM Propane Indoor (7.8/10) runs on propane.
Our take
Our favourite thing about the Takagi T-H3S-DV-N Condensing Indoor is an 8 GPM maximum flow, closely followed by condensing efficiency. Only 25 buyers have rated it so far (4.4/5), so treat the score as an early read. Our main reservation: no word on the gas input or the warranty. We'd pick it if you run one shower and the kitchen tap at once, rarely more; otherwise, put it next to the Rinnai RX160iN Condensing Smart Sense first.
Old tank out, unit on the wall, vent through the wall or the roof. 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), check the condensate drain and the neutralizer, and clean the inlet filter. Our flushing and descaling guide has the checklist.
Buyers give it 4.4/5, a strong record, well above this ranking's 4.1 average. Only 25 reviews so far, and our formula damps averages built on fewer than 50.
Before the Takagi T-H3S-DV-N Condensing Indoor ships, check your winter flow: 8 GPM is a best case, so run your January numbers in our calculator first.
Count the fixtures that run together on a busy morning (our calculator uses 2 GPM a shower, 1.5 for the kitchen), then compare with the maker's chart. Our sizing guide shows how.
A licensed plumber or gas fitter confirms the vent route, the combustion air and a gas line that can deliver its full input. Get that quote before you order; our installation guide lists what they will ask.
A condensing unit drips acidic water that needs a drain, often through a neutralizer. Our condensing guide explains the extra parts.
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 Takagi T-H3S-DV-N Condensing Indoor stacks up against the closest alternative in our ranking, the Rinnai RX160iN Condensing Smart Sense.
| Criterion | Takagi T-H3S-DV-N Condensing Indoor | Rinnai RX160iN Condensing Smart Sense |
|---|---|---|
| Our rating | 4.5/10 | 6.8/10 |
| Max flow | 8 GPM | 9 GPM |
| Efficiency | Condensing | Condensing, 0.97 UEF |
| Warranty | Not stated | 15 years (heat exchanger) |
| Buyer reviews | 25 · 4.4/5 | 70 · 4.2/5 |
Pick the Rinnai RX160iN Condensing Smart Sense if you want our higher-rated option (6.8/10), with more flow (9 GPM) and a condensing design; stay with the Takagi T-H3S-DV-N Condensing Indoor for a higher buyer rating (4.4/5).
We rate it 4.5/10 (fair), #4 of 5 in our high-efficiency condensing tankless water heater ranking. It is based on 25 buyer reviews averaging 4.4/5 and the specifications stated in the listing.
The listing states a maximum flow of 8 GPM. 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.
Yes, the listing says indoor mounting. That means a vent route to the outside, combustion air and a gas line sized for the unit, all as the maker and your local code require. A licensed plumber or gas fitter sorts that out.
Its listing states up to 8 GPM and a condensing heat exchanger. 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: count the fixtures that run together on a busy morning (our calculator uses 2 GPM a shower, 1.5 for the kitchen), then compare with the maker's chart. Our sizing guide shows how. Vent and gas line: a licensed plumber or gas fitter confirms the vent route, the combustion air and a gas line that can deliver its full input. Get that quote before you order; our installation guide lists what they will ask. The condensate: a condensing unit drips acidic water that needs a drain, often through a neutralizer. Our condensing guide explains the extra parts. 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 and 25 buyer reviews, read line by line and weighed with our published formula.
If the Takagi T-H3S-DV-N Condensing Indoor hasn't sold you yet, see where it ranks or browse all gas tankless water heaters.