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T-H3M-OS-N Outdoor Tankless High Efficiency Condensing Water Heater (NG)
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$934.86 each
In Stock
Get 2 Tomorrow, Jul 8
Order by 6PM, receive Tomorrow
MANUALS (4)
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Free Shipping This item ships free
Easy Returns No restocking fee for 90 days
Product Highlights
–
Natural Gas
6.6 MAX GPM
Outdoor Only
Direct Vent
Yes
22.875" Height
Description
–
The Takagi brand has been discontinued by the manufacturer as of December 31, 2025. Suggested replacement units will be available on our website and replacement parts will continue to be available as supplies last. If you'd like any further assistance, please contact our customer service team.
You may be eligible for rebates from your local utility company and state. Search your zip code in the link below for information about rebate programs that apply to you.Takagi Rebate Center
Overview:
The T-H3M is a new breed of tankless for smaller spaces. This model also uses existing 1/2" gas supply lines and inexpensive PVC venting to lower installation costs.
The T-H3M supplies hot water to domestic hot water systems (directly or indirectly) which can be used with storage tanks, recirculation systems, and/or domestic & heating applications.
The T-H3M is a high efficient, condensing tankless water heater perfect for residential applications. With gas inputs of 120,000 BTU, the T-H3M can produce enough hot water for two bathrooms in warmer climates or 1.5 baths in colder climates.
Specs
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| Energy Factor: | 0.93 |
|---|---|
| Inlet Gas Pressure: | 8.0"-14.0"W.C. |
| Product Type: | Tankless Heater |
| BTU (Max): | 120000 |
| BTU (Min): | 15000 |
| Application: | 2-3 Showers Residential |
| Max Flow (GPM): | 6.6 |
| Fuel Type: | Natural Gas |
| Vent Type: | Direct Vent |
| Type: | Condensing |
| Installation Type: | Outdoor Only |
| Energy Star Rated: | Yes |
| Height (Inches): | 22.875" |
| Width (Inches): | 13-7/8" |
| Depth (Inches): | 10-13/16" |
| Flow Rate at 70F Temp Rise (GPM): | 3.2 |
| Flow Rate at 50F Temp Rise (GPM): | 4.4 |
| Flow Rate at 40F Temp Rise (GPM): | 5.4 |
| Flow Rate at 60F Temp Rise (GPM): | 3.8 |
Questions?
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Call or text 888-757-4774
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Saturday – Sunday
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BTU (Min)
CURRENT ITEM
0.93
8.0"-14.0"W.C.
Tankless Heater
120000
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Product Reviews
4.78 out of 9 reviews
89% would recommend this product
5 star
89%
4 star
0%
3 star
11%
2 star
0%
1 star
0%
Showing 1-9 of 9 reviews
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Factory defect
I purchased 2 units one of them was defected took about a week to get the part from A O smit to replace . My customer was very disappointed I had to double work and get complains and give them credit to satisfy. Over all will not purchase this model anymore.
Jorjik
Los Angeles
2 years ago
Verified Buyer
Was this review helpful to you?
The work good
Thanks for this company good servis
Romeros plumbing
Hemet CA
2 years ago
Verified Buyer
Was this review helpful to you?
I would buy this tankless water heater again - and I did!
We have a long '60s ranch house with additions. For this reason, I segmented the hot water into two zones. I installed the first T-H3M-OS-N for the left side of the house after building a 270 ft sq master bathroom addition, and now I replaced the 50 gal NG conventional water heater the the same exact Takagi T-H3M-OS-N to cover the right side of the house. This is a great tankless, and couldn't recommend it more highly! This is the sixth Takagi tankless that I've installed and I'm sure that I'll install a few more from Supply House elsewhere in the future. Just be sure to ALWAYS use the correct specification gas regulator of the highest quality AND ALWAYS check your running gas pressure with a good manometer. If you do this, you will not have any problems. Never assume that your gas pressure out of the pipe is correct.
Forrest
Tallahassee, FL
3 years ago
Verified Buyer
Was this review helpful to you?
Takagi, Excellent water heater!
Its a trustable equipment, used at home for all services (two bathrooms, kitchen, laundry,), I installed a scale inhibition filter in cold water side to prevent scale in the heater, periodically review sediment filter.
Cantu
Mx
3 years ago
Verified Buyer
Was this review helpful to you?
Not sure how long it will last, but so far it is great!
The water heater was an easy install, especially because of the 1/2" gas line requirement. It now fits where a tank unit was without upgrading the gas line.
Pete
San Diego
3 years ago
Verified Buyer
Was this review helpful to you?
I have bought this for me , also asked my son 7 yrs back
We use it for all the residential use. Energy efficient as it strts gas only when the Hot water is used unlike water heater with 30-40 gallons of water.
Mike
Downey CA
4 years ago
Verified Buyer
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Very sure.
Great price and very fast delivery time.
Tommy NGuyen
San Diego
4 years ago
Verified Buyer
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My fifth Takagi Tankless and the best so far.
I've installed four different Takagi non-consdensing tankless water heaters over the last ten years for personal use in my different homes and one in a flip house, and this one, the T-H3M-OS-NG is the best yet. All have been exceptional performers, but this one is quietest and the exhaust is very cool and totally fume free. After experiencing this Takagi, I think that it is a no-brainer to pay the little extra for a High Efficiency Condensing model.
Forrest
Tallahassee, FL
5 years ago
Was this review helpful to you?
I would buy this product again. It was on time, undamaged
They gave me reasonable price, Delivery as promosed, Undamaged. I would buy product again.
MMeng
Downey CA
9 years ago
Verified Buyer
Was this review helpful to you?
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