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Eccotemp i12-NG Gas Indoor Tankless Water Heater & Vertical 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 Heater

On backorder, Expected availability date is 31st May 2023

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

Save time and money with this bundle of the i12-NG water heater and through-the-roof vent kit. It's an economical starter kit of venting pieces for a standard vertical installation.

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 roof 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

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. 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 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.

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

Venting pieces are made in USA by Z-Flex Z-Vent with lifetime warranty. Includes all the basic components for a quick and easy installation.

Your installation will probably require additional Z-Vent pieces to reach your ceiling and roof, as follows:
≈ Determine how many additional feet to reach the roof. Buy that length of straight pipe.
Condensation drain pipe may be required depending on your water heater manual guidelines and building code.

Contact us if you need to buy additional Z-Vent parts or assistance, or browse our Venting section at the top of this web page.

Please note this heater allows for a maximum vent run of 20 feet, subtracting 4 feet for each 90° elbow in the run.

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" backflow preventer in climates that have freezing weather
  • qty 1 3" adjustable roof flashing. Unless you specify differently, we will ship normal roof slope flashing.
  • qty 1 3" top support, storm collar
  • qty 1 3" rain cap

The stainless steel is alloy is AL-294C with a lifetime warranty from Z-Flex, and is Category II/III and UL approved. Made with USA steel.

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.