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Eccotemp i12-NG Natural Gas Indoor Tankless Water Heater

Original price $499.00 - Original price $518.95
Original price
$499.00 - $518.95
Current price $499.00


Eccotemp i12-NG Indoor Tankless Water HeaterEccotemp i12-NG Natural Gas Indoor Tankless Water Heater

Eccotemp created the i12-NG Natural Gas powered water heater with top-of-class design. It is unique among tankless water heaters on the market today. The exterior case is made of black Gorilla Glass. You can control the temperature with the touch screen, which has an LCD output temperature and gallons per minute ("GPM") flow display.

This bundle with vent kit makes it quick and easy to get hot water for vacation cabins, cottages and homes with limited simultaneous points of use. Calculate your flow rate and temp rise to ensure it will work for you.

The i12-NG digital display control functions and the internal exhaust fan are powered by the 120 volt UL listed power cord, using only 2 watts while in idle, standby mode, and 1.07 Amps during operation. This makes it a super energy efficient appliance.

Water temperature heating delta/increase capability:
≈ 35°F to 40°F at a flow rate of 3 GPM
≈ 77°F at a flow rate of 1.5 GPM

Download Eccotemp i12 Manual

More Features

  • Gorilla Glass casing
  • Child lock controls
  • Fully automatic temperature controls
  • LCD temperature display
  • Power vented for safety and efficiency
  • Tested safe electronic ignition
  • Stainless vent kit included (2.5" not 3"): 18" termination pipe, wall thimble (for 4 to 7" wall thickness), and 90 degree elbow with backflow preventer
  • Uses gas only when hot water tap is on and flowing
  • Includes 5-foot power cord with plug
  • UL Listed power cable
  • TEN year warranty on heat exchanger in residences; two years in commercial installations. FIVE year warranty on parts. For warranty replacement shipping within 30 days, Eccotemp pays shipping both ways. After 30 days, Eccotemp pays for shipping to customer.


  • 1/2" NPT water connection
  • 1/2" gas connection. 1/2" to 3/4" adapter included
  • Weight: 33 pounds
  • Dimensions: 15" W x 24" H x 4" D
  • Requires standard 120 volt electric outlet with a breaker size of at least 2 amps.
  • Minimum gas rate of use: 25,000 BTUs
  • Maximum gas rate of use: 80,000 BTUs
  • Energy efficiency rating: 85%
  • Minimum water pressure of 14 psi. Minimum water flow rate of 0.75 GPM.
  • Minimum Inlet Gas Pressure: 4” W.C. (1Kpa)
  • Maximum Inlet Gas Pressure: 10.5'' W.C. (2.61Kpa)
  • Manifold Pressure: 3.05'' W.C. (0.76Kpa)
  • Hot water capacity range: 0.6 to 4.8 GPM
  • Heat exchanger material: copper
  • Maximum operating temperature: 140°F. Control panel temperature range: 90°F to 140°F
  • Ratings of gas appliances are based on sea level operation and need not be changed for installations at elevations up to 2,000 feet. The i12 is not recommended for elevations greater than 2,000 feet.

Operate on well water systems at a range of 50 to 60 PSI.

The maximum recommended incoming water temperature is 80°F. Not recommeded for recirculation applications. Instead, consider an electric tankless water heater.

Frequently Asked Questions ("FAQ")

Q1: Is the heated output water potable (drinkable)?
A1: Yes! Eccotemp has tested the heated output water as acceptable according to water safety standards.

Q2: What is the maximum recommended altitude?
A2: Customers have reported good operation at 6500 feet. The manual states, "Ratings of gas appliances are based on sea level operation and need not be changed for installations at elevations up to 2,000 feet. Unit not recommended for elevations in excess of 2,000 feet.". As altitude increases, gas appliances normally have a fuel efficiency loss (derating), and the fuel-to-air ratio changes with less oxygen in the air.