TK-110U-I Indoor Tankless Water Heater
by Takagi

Looking for a powerful yet compact tankless water heater for your home? Takagi Tankless Water Heaters are on the forefront of tankless technology, and offer many features that you're sure to appreciate. Keep a constant flow of hot water available for the many uses around the house with a tankless water heater from PlumbingSupply.com®!
We also offer many more tankless water heaters by Takagi:
TK-110U-E (outdoor) - TK-310U-I - TK-310U-E (outdoor) - TK-510U-I - TK-510U-E (outdoor)

Takagi TK-110U-I - Tankless Gas Water Heater for Indoor Installations

Takagi TK-110U-I indoor tankless water heater
  • The TK-110U-I is a compact and powerful tankless water heater designed for indoor installations (wall brackets built-in)
  • Unlike regular tank style water heaters, this unit will never run out of hot water
  • With it's compact dimensions of only 20.5" x 13.75" x 10.0", this water heater can be installed nearly anywhere, often allowing for installation far closer to the main point of use than tank-type heaters, which reduces travel-time through pipes and wastes less energy
  • Heats water flows ranging from .75 to 6.6 gallons per minute, a rate that is typically ideal for light residential applications with one or two bathrooms, such as a small home, apartment, condo or cabin
  • Computer-controlled burners and electronic ignition use only the amount of gas required according to the demand, which significantly increases this unit's efficiency and can help decrease your gas bill
  • Excellent safety features including built-in freeze protection, flame sensor, overheat cutoff fuse, and surge protection
  • Copper heat exchanger provides 2.5x better heat transfer than stainless steel which stabilizes outgoing water temperature more quickly and reduces pressure drop across the heat exchanger
  • Field convertible from natural gas to liquid propane with included conversion kit
  • Complies with ultra-low NOx regulations of less than 14 ng/J (<20ppm)
  • Can be used with water storage tanks, recirculation systems, and combined domestic and heating applications
  • Includes a built-in power cord and temperature controller, which allows the default factory setting of 120°F output temperature from the water heater to be adjusted within the range of 100°F to 140°F, and also works as a diagnostic tool that will give a concise error code whenever there is a problem with the unit
  • View detailed specifications
  • View owner's manual
  • View installation manual
  • View gas conversion instructions
  • Looking to install this tankless water heater outside? Click here
Takagi TK-110U-I Indoor Tankless Water Heater $681.29
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Please note: For potential safety reasons, we do not recommend using PVC to vent gas tankless water heaters. For the best results, we recommend using Category 3 stainless steel gas vent pipe for all gas tankless water heaters.



Frequently Asked Questions

Q. "What type of vent do these tankless water heaters require?"
A. These tankless water heaters require Category III stainless steel vent only.

Q. "If these units don't have a tank, how do they know when to turn on?"
A. These tankless water heaters have a flow switch built into them. When you turn on the hot side of a faucet the water begins moving. Once the water is traveling at minimum flow rate for the heater, the flow switch will turn on the gas.

Q. "Why can't I install the TK-110U-I myself?"
A. Improper installation of the TK-110U-I could create carbon monoxide gas and other dangerous gases. Installation of this unit by persons other than professionally trained technicians voids the warranty.

Q. "What's the difference between a conventional flue and a direct vent?"
A. A conventional flue is what most people are familiar with. It typically consists of a double-wall flue pipe going from the top of the heater through the roof, venting outside. The fixture draws its combustion air from the space around it (utility room, garage, hallway, etc.). A direct-vent unit vents and draws its combustion air through a specially designed pipe from the outside via an adjacent wall.

Q. "Can I use PVC to vent this tankless water heater?"
A. No. The temperature of the exhaust is too high to safely use PVC as venting material. We never recommend PVC as venting even where the ideal exhaust temperatures would technically allow it due to a much higher incident of dangerous issues associated with PVC venting on poorly-maintained gas tankless water heaters.

Q. "Your products specify the 'temp. rise' based on the GPM flow; what do you mean by this?"
A. Temperature rise is the amount the heater raises the temperature of the incoming water, based on the flow rate shown of that water.

Q. "What's the first hour rating of this water heater?"
A. Traditional tank water heaters have a first hour rating which is determined by the amount of hot water the heater can produce in an hour when starting with a full tank of hot water. As tankless water heaters do not start with a tank of hot water, they don't really have a first hour rating the same way a tank water heater does. Instead, tankless water heaters have a gallons per hour rating, which is determined by how many gallons per hour the tankless water heater can produce when raising the incoming water temperature a specified amount.

All Takagi tankless water heaters must be installed by a licensed professional.


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