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**This product qualifies for the Federal Tax Credit. Please see the bottom of this description for tax credit details.

The T-K3-OS is one of Takagi's smaller tankless water heaters. At 13.8 inches wide and weighing only 40 pounds, its ultra-compact design allows it to be mounted on a wall or installed between two wall studs using Takagi's TK-RBO2 recess box, so it's even more inconspicuous. Since it can only be installed outside, the T-K3-OS is ideal for warmer climates.
The T-K3-OS features a built-in power venting system, but unlike any of its predecessors, the new tankless water heater does not require any additional Category III venting or vent caps, making installation one step easier for its installers.
It can provide an unlimited supply of hot water continuously because there is no storage tank to heat and reheat. The T-K3-0S starts heating water at 0.5 gallons per minute (GPM), and can keep that endless supply of hot water running from as low as 0.4 GPM up to a maximum flow rate of 7.0 GPM.
Takagi's newest tankless water heater also features a thermal rating of 83% for both liquid propane and natural gas, so it is extremely efficient and environmentally friendly. Since tankless water heaters only burn gas when hot water is needed, installing this unit can help homeowners save up to 45% on their monthly gas bills.
The T-K3-OS also offers four separate temperature settings, ranging from 113 to 167 degrees, so it does not require the use of a separate remote control.
Capacity: 2 to 3 Bathrooms
Natural Gas Input - Min. 11,000 Btu - Max. 190,000 Btu
LPG Input - Min. 11,000 Btu - Max. 190,000 Btu
Gas Connection - 3/4" NPT
Water Connection - 3/4" NPT
Natural Gas Pressure Inlet - Min. 5.0" WC - Max. 10.5"WC
Weight - 40 lbs
Dimensions - 20.5" x 13.8" x 8.5"
Ignition - Electronic Ignition
Electrical Supply - AC 120V (60 Hz)
Water Pressure - Min. 15 psi - Max. 150 psi
Natural Manifold Pressure - 2.8" WC
LP Manifold Pressure - 3.2" WC

**Federal Tax Credit Information:

The purchase and installation of this energy-efficient product in your home qualifies you for a Federal Tax Credit.

The 2010 tax credit is worth 30% of the item's total cost (including installation), up to a maximum of $1,500. The credit is applicable on products placed in service between January 1, 2009 and December 31, 2010 and installed in your primary residence.

The 2011 tax credit extension is worth 10% of the item's total cost up to of $500 (installation cost is not included). The credit is applicable on products placed in service between January 1, 2011 and December 31, 2011 and installed in your primary residence. There is a $500 cap for the 2011 tax credit extension, so if you have claimed $500 or more since January 1, 2005, you are not eligible for the credit. Additional caps have been placed on specific product categories, including a $300 cap for water heaters and a $150 cap for boilers.

Since this non-solar propane water heater has either an Energy Factor greater than or equal to 0.82 or a thermal efficiency of at least 90%, it qualifies for the Federal Tax Credit.

To apply for the tax credit, you must file and submit the relevant tax forms. For products "placed in service" in 2011, you would take the tax credit on your 2011 income taxes. Remember to save your receipts and the Manufacturer's Certification Statement for your records.

Please see Federal Tax Credits for Consumer Energy Efficiency for additional information.
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2-3 Showers

Product Type:

Tankless Heater

Fuel Type:


Energy Factor:


Gas Input:

8" W.C.



Height (Inches):


Min Flow (GPM):


Max Flow (GPM):


Flow Rate:

0.5-7 GPM





Depth (Inches):


Vent Size:


Vent Type:

Stainless Steel



Water Connection:


Gas Connection:


BTU Input:


Temperature Range (F):

113°F - 167°F


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