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Series 200 Ultra Low-NOx Non-Condensing Indoor Tankless Water Heater (10 GPM, NG/LP)
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$973.19 each
In Stock
Get 22 Tue, Jul 7
Order by today, receive Tuesday
MANUALS (3)
This item replaces: T-D2-IN-NG, T-D2U-IN-N, T-D2-IN-LP
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Free Shipping This item ships free
Easy Returns No restocking fee for 90 days
Product Highlights
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Natural Gas, Propane
10 MAX GPM
Indoor Only
Power Vent, Direct Vent
No
20.5" Height
Description
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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.
Think Green, Save Green. Rebate and incentive programs provide cash-back to consumers for the purchase of appliances that meet certain energy efficiency standards. Most states are offering rebates in the $50 to $250 range. You can search for rebates in your area from here.
Please note: This unit comes Natural Gas as standard, but can be easily converted to Propane with the supplied gas conversion kit.
Please note: TK-510U CAN BE USED IN BOTH RESIDENTIAL AND COMMERCIAL APPLICATIONS
Fully modulating, gas fired, tankless water heater with sealed combustion and power vented flue. Indoor and outdoor models available for residential and commercial applications. Supplies hot water to domestic hot water systems and can be used with water storage tanks, recirculation systems, and/or combined domestic & heating applications.
Series 200 incorporates several new features including a combustion system that can easily be field converted from natural gas to propane with components supplied in the box. The maximum vent length has increased to 60'. The indoor models will have an integrated temperature controller and factory installed power cord. The outdoor models will include a remote control as a standard feature.
Features:
- This unit is NOT approved for installation in Manufacture Homes and is not suitable for space heating applications only.
- Capacity: 2 to 4 Showers
- Field Convertible from Natural Gas to Propane
- Complies with SCAQMD rule 1146.2 and other air quality management districts with similar NOx emission requirements of 14 ng/J or 20 PPM.
- Maximum flow rate of 10 GPM at 35°F temperature rise (4.7 GPM at 70°F rise)
- Copper HEAT EXCHANGER: 25x better heat transfer than stainless steel thus stabilizing outgoing water temperature quicker and reducing pressure drop across the heat exchanger
- Indoor models include a built-in temperature controller and a factory-installed power cord as standard features.
- 15-year limited warranty on heat exchanger in residential applications, 10-year limited warranty on heat exchanger in commercial applications, 5-year limited warranty on all parts
- Complies with Lead Free standards
- Easy-Link up to 4 units (no additional parts or accessories needed)
- Multi-link up to 20 units
Specs
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| Application: | 2-4 Showers Commercial Residential |
|---|---|
| Product Type: | Tankless Heater |
| Fuel Type: | Natural Gas Propane |
| Vent Type: | Power Vent Direct Vent |
| Installation Type: | Indoor Only |
| Energy Factor: | 0.82 |
| Vent Size: | 4" |
| BTU (Min): | 15000 |
| BTU (Max): | 199000 |
| Inlet Gas Pressure: | 4.0-10.5"W.C |
| Water Connection: | 3/4" |
| Max Flow (GPM): | 10 |
| Features: | Ultra Low NOx |
| Includes: | Gas Conversion Kit Integrated Temperature Controller Power Cord |
| Energy Star Rated: | No |
| Height (Inches): | 20.5" |
| Width (Inches): | 13-3/4" |
| Depth (Inches): | 10" |
| Type: | Non-Condensing |
Contact
+
Happy Independence Day!
Our Customer Support will be closed today in honor of Independence Day. We will be back tomorrow to answer your questions.
Call or text 888-757-4774
Special Hours
Closed Now
Monday – Thursday
8am–7:45pm
Friday
9am–7:45pm
Saturday – Sunday
9am–5:45pm
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Product Reviews
4.72 out of 43 reviews
93% would recommend this product
5 star
86%
4 star
2%
3 star
9%
2 star
2%
1 star
0%
Customer Images
Most Liked Positive Review
Takagi On Demand Water Heater
We purchased this water heater from Supply House to replace a Takagi TK-3 that was had problems. As a homeowner I was a bit skeptical to replace the On Demand system without hiring a Pro however since the plumbing and gas lines were already installed with coupling fittings and the porting locations were nearly the same between the two models I took the leap and self installed. All is good no leaks and really like the new model. Works exactly as we expected. Service and support was perfect! Delivery was quick and shipping was the next day from a warehouse in Nevada.
VS
Most Liked Negative Review
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Supply House-Great, Takagi- not so- failing parts
The Service from Supply House was great, delivery in about 3 days. Would definitely buy from them again. Takagi- meh. Tankless- 25 years? This was a replacement on a Takagi TWH that was installed about 2007. So, about 16 years? Motherboard failed, no replacements available, out of production, had to purchase new. Unit arrived with defective gas control valve, fortunately installer (Precision in Irvine, CA) was a WH installation pro, had replacements in stock- brought 2. One of the replacements also failed. So the Takagi parts failed 2 of 3 times. Not the fault of Supply House, this came in original Takagi pkng., sealed from factory.
Showing 1-10 of 43 reviews
Great replacement
The unit is a great replacement for my old TK-2.
Ron
Buena Vista Co
9 days ago
Verified Buyer
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Very easy install
This unit married up to the existing vent system. No new roof holes.
JCF
Goleta, CA
4 months ago
Verified Buyer
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I would recommend the more expensive option from Takagi.
The cost of the vent is almost as much as the unit itself. Takagi is a fantastic instant water heating product. The next system up allows for PVC exhaust which is substantially less money.
Salida Builders
Salida, cO
5 months ago
Verified Buyer
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I have been recommending this product.
This product is suitable for the five major boroughs of New York City. It is practical to replace the traditional old barrel hot water heater with a wall-mounted hot water heater, which saves space and money.
KB
NyC
9 months ago
Verified Buyer
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Great service, as always
Excellent product. Shipped quickly and arrived in great shape.
H2O
Redway, Calif.
9 months ago
Verified Buyer
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SupplyHouse.....My Go-To Place for HVAC
I placed My order around 3PM and was promised the Tankless unit would be delivered the next day. I checked later that evening and found the unit was not shipped yet. I figured it missed the pickup time. WELL...I was WRONG. When I checked the next morning it had been picked up around 3AM!!! and It was out for delivery! I have never seen this happen before and to say the least, I was impressed. Best service, best prices, and a great company to do business with. HIGHLY RECOMMENDED!.
Ron G
New York
11 months ago
Verified Buyer
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Not sure now
Since it's been installed, I've had nothing but trouble with this unit, keeps giving a 992 error, and now my fault, I had two TK3 running in the same location for 14 years with no issues. One of the TK3 went bad around two years ago and replaced it with a 510u and it's been running great. My second TK3 died about three weeks ago and have been fighting it ever since.
Shebee
Forest Grove, Oregon
12 months ago
Verified Buyer
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Easy install and great performance so far!
This unit us being operated as a boiler providing hot water to hydronically heated conctrete floors (aprox 1500 sf.), and for a 50Gal side arm water heater tank with priority over the floor. Replaced an existing 25 year old Takagi TM-1 unit, was happy to be able to get a unit that would use the same venting as the original unit.
John S.
Colorado Springs, CO
1 years ago
Verified Buyer
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Perfect water heather
This is a great water heather, the quiality of the construction is really good, installation was not complicated just make sure to read the manual to set it up properly, I used the conversion kit that came with it for propane and was very straightforward to convert, the performance is great, a little noisy but a big improvement from the one it replaced, more than enough for a 2 bedroom condo.
LuisA
San Diego
1 years ago
Verified Buyer
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Good water heater - good supply company
Love Takagi - Replacing a 20+ year old unit with a new one. Would have loved to fix the failed one but it was not worth buying a new circuit board.
Placed an order with Supplyhouse online and next thing you know, it is delivered. No drama or nonsense, just action.
Greg
LA, Calif
2 years ago
Verified Buyer
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Product Q&A
1 Question1 Question
Q: What water temperature will this unit heat to.
Asked by Stub 3 years ago
Add your answer
Verified Reply- SupplyHouseHello, thanks for writing in. Water temperatures over 125 °F (52 °C) can cause severe burns instantly from scalding. The water temperature is set at 120 °F (50 °C) from the factory to minimize any scalding risk.
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