T-H2-OS Takagi Tankless Outdoor Water Heater (Natural Gas) Zoom

T-H2-OS Takagi Tankless Outdoor Water Heater (Natural Gas)


Brand: Takagi

T-H2-OS-NG has been discontinued.
Suggested Alternative:
Brand: Takagi


Application: 3-4 Showers
Product Type: Tankless Heater
Fuel Type: Natural Gas
Installation Type: Outdoor Only
Energy Factor: 0.91
Inlet Gas Pressure: 5.0-10.5"W.C.
Manifold Pressure: 2.7"W.C.
Weight (lbs): 70 lbs
Warranty: 12 Year Ltd. Warranty on Heat Exchanger/ 5 Year on Parts
Energy Star Rated: Yes
Height: 25.6"
Width: 18.5"
Depth (Inches): 12.4"
Min Flow (GPM): 0.5
Max Flow (GPM): 9
Flow Rate:
0.5-9.0 GPM
Gas Input: 13000-199000 BTU/h
Water Connection: 3/4"
Gas Connection: 3/4"
Temperature Range (F): 100°F to 185°F
PSI Range: 15-150 psi

Description for Takagi T-H2-OS-NG

Note: Isolation valves are not included but are recommended for installaltion.

Capacity: 3 Showers + 1 Appliance
Flow Rate: 0.5 to 9.0 GPM
Max Temp. Range: Up to 185ºF
Gas Inputs: 13,000-199,000 Btu/h
Energy Factor: 0.91

The T-H2, Takagi's greenest model, is the 2nd Generation High Efficiency Tankless unit with an average efficiency of 92% with natural gas (estimated) and 95% with propane (estimated). At a change in temperature of 60ºF in warmer areas - where the winter ground water is 60ºF and with the output set at 120ºF - the unit will provide 6.1 GPM, or 366GPH. In other areas where the input temperature may be 40ºF or less, you can expect a flow rate of about 4.6 GPM or 276 GPH.

The T-H2 can provide at least three showers' worth of water simultaneously along with one appliance at input temperature of 60ºF or greater.

The T-H2 can be vented with PVC, providing 0 clearance for DV installations. PVC venting can be used in all applications and 3" exhaust venting is coming soon. This state-of-the-art tankless water heater uses not one, but two heat exchangers to maximize the unit's energy efficiency, resulting in the higher-than-average efficiencies stated above. The primary heat exchanger is made of "Heat Resistant Alloy" HRS35 Copper, Takagi has also added a "High Corrosion Resistant Stainless Steel" #316L secondary heat exchanger to recover waste heat from the vent stack before it leaves the unit to preheat the incoming ground water. This second heat exchanger and the resulting condensation that forms from the high efficiency operation, classify it as a "Condensing" Water Heater.

With a variable gas input up from 13,000 Btu/h to 199,000 Btu/h and with its high efficiency, the T-H2 can deliver 9.0 gallons (Max.) of hot water per minute under ideal conditions and when you Easy-Link 4 units together you can produce up to 36GPM (Max.) as a result, the unit will meet the needs of large homes, as well as light commercial and industrial applications. Able to deliver water up to 185ºF, the T-H2 is appropriate for sanitary applications needing 180ºF water to meet code requirements.

The T-H2 features sixteen temperature presets for flexibility of installation. To achieve any temperature other than the sixteen presets, the user will require the TM-RE30 temperature controller.

T-H2-OS Takagi Tankless Outdoor Water Heater (Natural Gas)


by PowerReviews
T-H2-OS Takagi Tankless Outdoor Water Heater (Natural Gas)

(based on 2 reviews)

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Reviewed by 2 customers

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Expensive but effective

By Jeff

from San Luis Obispo, CA

Verified Buyer

Comments about T-H2-OS Takagi Tankless Outdoor Water Heater (Propane):

I'm using this in conjunction with a 3 panel Solar Hot Water heating system. It boosts the water temperature easily to 120 degrees and eleminates the need to use the storage tanks back-up Electrical element to make temperature. Without a recirculator, it takes about 30 seconds to get warm water and about 45 to get hot water from the nearest faucet.


Highly Recommend!

By Robin, The House Manager

from Santa Barbara

Verified Buyer

Comments about T-H2-OS Takagi Tankless Outdoor Water Heater (Natural Gas):

I was not sure about switching from my standard Tank Heater to a Tankless Heater. We installed the Tankless Water (outdoors) to ensure it would properly be vented. The heat is fantastic, the unlimited supply is amazing... the cost savings is wonderful. We also have hard water so now we are saving on EXPENSIVE water bills because our Salt Hard Water System no longers needs to rinse the Tank every 48 hours dumping gallons of unused water down our drain! The Tankless Water Heater SOLVES these problems and keeps an unending flow of HOT WATER. Thrilled!!!

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