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Eccotemp i12-NG Gas Indoor Tankless Water Heater & Horizontal Vent Kit

Original price $699.00 - Original price $718.95
Original price
$699.00 - $718.95
Current price $699.00


Eccotemp i12-LP Indoor Tankless Water HeaterOn Backorder, the Expected availability date is 31st May 2023

Eccotemp i12-NG Natural Gas Indoor Tankless Water Heater & Horizontal Vent Kit

Save time and money with this bundle of the i12-NG water heater and through-the-wall vent kit. All the basic venting pieces for a standard wall-hung installation are here.

Eccotemp created the i12-NG with top-of-class design. It's 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 a few simultaneous points of use. Calculate your flow rate and temp rise to be sure 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
  • Uses gas only when hot water tap is on and flowing
  • Includes 5-foot power cord with plug
  • UL Listed electrical components
  • 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 plus 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.
  • Hot water capacity range: 0.6 to 4.8 GPM
  • Energy efficiency rating: 85%
  • Minimum gas rate of use: 25,000 BTUs
  • Maximum gas rate of use: 80,000 BTUs
  • 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)
  • 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. Electric tankless water heater are recommended instead.

Included: Horizontal Vent Kit with 3" Diameter Single Walled Stainless Steel

Vent parts are made by Z-Flex Z-Vent with lifetime warranty. Includes all the basic components for a quick and easy installation. Your installation may require additional pieces. Please contact us for assistance.

Included pieces

  • qty 1 2.5" to 3" diameter stainless steel adapter. Converts the i12 flue opening 2.5" to a standard 3" diameter vent system. Total length is 6".
  • qty 1 3" diameter Universal Appliance Adapter
  • qty 1 3" diameter 90° elbow
  • qty 1 3" diameter 1 foot long pipe
  • qty 1 3" diameter wall thimble
  • qty 1 3" diameter termination hood with backflow preventer in climates that have freezing weather

The stainless steel is alloy is AL-294C with a lifetime warranty from Z-Flex, and is Category 2, 3, 4, and UL approved.

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.