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Eccotemp FVI12-NGV FVI12 Indoor 4.0 GPM Natural Gas Tankless Water Heater Vertical Bundle

$ 579.00

This bundle includes the FVI12-NG Tankless water heater, 2.5" to 3" Stainless steel adapter, and the 3" Vertical vent kit.

The Eccotemp FVI12-NG is a Natural Gas-fired, Indoor Tankless Water Heater designed for small to medium hot water production where you need more than one hot water application at the same time. This model is perfect for vacation cabins, cottages, and smaller homes. The Eccotemp FVI12 offers a 45-degree Fahrenheit temperature rise when operating at 4 Gallons Per Minute maximum flow capacity and a 77-degree Fahrenheit temperature rise at 2.3 Gallons Per Minute. Included in the bundle is a Vertical Stainless Steel Vent Kit, ready to install.  The Eccotemp FVI12-NG's 120-volt UL listed power cord powers the internal exhaust fan and digital display and only pulls about 2 watts idle and 1.07 Amps during operation, making it ideal when energy conservation is paramount.


Product Features:

  • Sleek modern design
  • Digital temperature display
  • True 1/2" NPT water fittings
  • Manual water temperature controls
  • Natural Gas Powered
  • 4 GPM flow capacity
  • Power ventilation for safety, efficiency, and venting options
  • Tested-Safe Electronic ignition system
  • Fully independent gas and water controls
  • Precise temperature and water flow adjustment
  • Uses gas only when hot water is on
  • Requires standard household 120-volt electric outlet
  • UL listed electrical components
  • Energy factor: 79%
  • Maximum / Minimum gas rate: 25,000 to 74,500 BTUs


What’s Included:

  • 3" Stainless Steel Vertical vent kit
  • 110-volt UL Listed Power Cord
  • 2.5-3" Stainless Steel Adapter
  • Hardware Pack
  • Instruction Manual
  • 2-Year Limited Warranty


2.5 to 3" Stainless steel adapter

This stainless steel adapter can be used with the Eccotemp FVI12 series taking it from a 2.5" to a standard 3" vent system. Total length is 6". Note, you may need to purchase a straight pipe piece with a backflow preventer to ensure that freezing air does not come back through the vent pipe.

Eccotemp Vertical Ventilation kit 3"

This 3" single walled Z-Flex Vertical Vent Kit is for vertical installations only. You will need to purchase an additional Z-Vent straight pipe. You will need to determine how many additional feet as well as need a condensation drain. Also, remember a max vent run of 20’ subtracting 4’ for every 90-degree elbow in the run.


  • 1 x 3" Rain Cap
  • 1 x 3" Top Support/Storm Collar
  • 1 x 3" Adjustable Roof Flashing (specify either Normal or Steep Flashing)
  • 1 x 3" Paloma Appliance Adapter
  • 1 x 3" Backflow Preventer 

Z-Vent special gas vent kits are all made of AL-294C stainless steel and are category II/III and UL compliant.

FVI12 Manual 

FVI12 Warranty

The Eccotemp FVI12 has been tested for use at elevations up to 2000 feet. Installation and use of the Eccotemp FVI12 above 2000 feet may affect overall product efficiency and performance. Installation and use of the Eccotemp FVI12 above 5000 feet is not recommended.

IMPORTANT NOTE: Cannot be used for HYDRONIC SYSTEM, RECIRCULATING, or FLOOR HEATING nor be used with a bilge pump.