Open Box - 20HI Indoor 6.0 GPM Natural Gas Tankless Water Heater with Free Extended Warranty

Open box models are tested to original working condition and come with their original manufacturer warranty PLUS free 1-year extended warranty.

The Eccotemp 20HI Indoor Natural Gas Tankless Water Heater is one of the largest indoor models of the Eccotemp tankless line. Rated at an impressive 6.0 gallons per minute (GPM) and 150,000 BTU per hour, the Eccotemp 20HI-NG can meet all the hot-water needs of a standard home or apartment with one or two bathrooms, as well as smaller commercial applications. The compact, wall mounted Eccotemp 20HI-NG is powered by natural gas. The Eccotemp 20HI-NG is ready to install with its 110/120-volt UL listed power cord powering the internal exhaust fan and digital display. With its fully automated control system, the Eccotemp 20HI-NG only pulls about .6 amps during operation, making it an ideal choice for any standard-sized home. 

Product Features:

• Rated for 2-3 applications used simultaneously means that taking a shower and running two sinks at the same time is effortless. The Eccotemp 20HI is ideal for normal hot water heating applications in ANY size residential single-family home.
• Best in class 10-year product warranty offers peace of mind that the Eccotemp 20HI will withstand the time and use you need. The Eccotemp 20HI can be complemented with our patented one of a kind EZ-Flush descaling kit to ensure your tankless water heater is running at maximum efficiency all year long.
• Rated at 6.0 GPM at 150,000 BTU with a temperature rise of 38 degrees this ultra-efficient tankless water heater is ideal for just about every single-family home in the US and Canada. With Advanced incoming and outgoing water temperature sensor technology, you always have total confidence when it comes to safety.
• CSA certified for installation in the US and Canada. This tankless water heater meets and exceeds all safety and efficiency requirements according to the DOE. With an Energy Factor Rating of .83, you can have peace of mind knowing this tankless water heater is ideal for individuals looking to save money.
• Advanced Generation 3 Computer board with high performance processing and smart adjust technology built in. Our proprietary developed programming meets and exceeds today’s consumer demand needs. Easy, affordable 3” stainless steel venting makes the Eccotemp 20HI tankless water heater economical and affordable to install.

What's Included:

• 20HI Indoor Natural Gas Tankless Water Heater
• 110/120-Volt UL Listed Power Cord
• Gas Shut-Off Valve
• Instruction Manual
• Installation Hardware
• 10 Year Heat Exchanger/5 Year Parts Warranty

Installation Clearances:

• The water heater must be installed on a fire-retardant area and must be away from all flammable materials. Clearance should be 1.75 ft to the left and right side of flammable materials, and 6.75 ft to the front.
• 2" clearance from wall
• 1' on both sides (left and right) from anything flammable
• 3' from any window, overhang, awning
• 18" from the ground

20HI Product Info and Manual
20HI Warranty

The Eccotemp 20HI has been tested for use at elevations up to 2000 feet. Installation and use of the Eccotemp 20HI above 2000 feet may effect overall product efficiency and performance.

IMPORTANT NOTE: Cannot be used for HYDRONIC SYSTEMS, RECIRCULATING, or FLOOR HEATING.

Please Note: Failure to clean and descale your water heater quarterly can result in lime and sediment build up within the heater, which can void your warranty! We recommend using our Eccotemp EZ-Flush System Descaler Kit to ensure a clean, energy efficient, long lasting heater! Click here for details.


All purchases valued at $75 or above will be shipped with SIGNATURE REQUIRED. If you wish to remove the SIGNATURE REQUIRED please contact Customer Service. Please Note: By opting out of SIGNATURE REQUIRED, you release Eccotemp from all liability of lost or stolen packages. Call 1-866-356-1992 or chat with us here to speak with a customer service agent.