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Eccotemp FVI12-NG Indoor Tankless Water Heater

Original price $399.00 - Original price $418.95
Original price
$399.00 - $418.95
Current price $399.00

Eccotemp FVI12-NG Indoor Tankless Water Heater


The Eccotemp FVI12-NG Indoor Tankless Heater is a natural gas powered indoor tankless water heater designed specifically to produce small to medium hot water in situations that require more than one hot water source simultaneously. The Eccotemp FVI12-NG tankless heater is ideal for cottages, vacation cabins, and smaller houses.

The Eccotemp FVI12-NG tankless hot water heater comes with a ready-to-install horizontal stainless steel vent kit. The 110-volt UL listed cord powers the digital display and internal exhaust fan. It only consumes about 2 watts on standby and 10 watts during operation: truly energy-efficient.


• Sleek, modern design
• Natural gas powered
• Includes 2.5" not 3" stainless steel vent kit: 18" termination pipe, wall thimble, and 90 degree elbow with backflow preventer
• Power ventilation for efficiency, safety and venting options
• Delivers three (3) GPM of piping hot water
• Digital temperature display
• Tested-Safe Electronic ignition system
• Precise water flow and temperature adjustment
• Fully independent water and gas controls
• UL listed electrical components
• CSA certification
• Uses gas only when the hot water is on
• Freeze protection protects the heater's internal components from freezing when plugged in. (Does not protect external valves and pipes.)


• Manual water temperature controls
• True 1/2" NPT gas and water fittings
• 1/2" gas connection
• 74,000 BTU
• DOE Energy Factor of 79%
• Maximum water flow rate is 4 GPM
• Heats water by 45 degrees F at a flow rate of 4 GPM. Heats water by 77 degrees F at a flow rate of 2.3 GPM.
• Maximum operating temperature is 140F
• Requires standard household 120V electric outlet. 60Hz, 2 amps.
• Minimum recommended operating PSI is 14. The recommended PSI is 14 + pipe pressure loss + shower/faucet pressure loss + 5 PSI safety margin. These values are for pressure at the heater. To supply hot water to upper floors, add 0.44 PSI per foot.
• Copper heat exchanger
• Weighs only 33 pounds
• Unit measures 15" x 24" x 4"
• 2 year warranty

Click here for Installation Use and Care Manual

Frequently Asked Question ("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: Eccotemp stated in 2018 that the FVI12-NG has been tested to operate at 5500 feet. And customers have reported good operation at 6500 feet. The manual which was published before 2018 states that the maximum recommended elevation is 3000 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.