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Eccotemp 20HI-NG Indoor Natural Gas Tankless Water Heater

$549.00
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Overview — Eccotemp 20HI Indoor 6.0 GPM Natural Gas Tankless Water Heater

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.
  • Uses standard 3/4" NPT water and gas fittings


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 affect overall product efficiency and performance. Installation and use of the Eccotemp 20HI above 5000 feet is not recommended.

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!

All Whole Home Water Heater purchases will be shipped with SIGNATURE REQUIRED. If you wish to remove SIGNATURE REQUIRED from your shipment please contact Customer Service immediately to have it removed. Please Note: By opting out of SIGNATURE REQUIRED you release Eccotemp Systems, LLC from all liability of lost or stolen packages.

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Warranty — Eccotemp 20HI Indoor 6.0 GPM Natural Gas Tankless Water Heater

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Includes all applicable Manufacterer Warranties

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Specs — Eccotemp 20HI Indoor 6.0 GPM Natural Gas Tankless Water Heater

Current Stock:
Availability: Usually ships within 1 to 6 business days
Power Type Natural Gas (NG)
Applications Apartment/Condo/Townhome
Applications Tiny Home
Applications Mid-Size Home
Applications Whole Home
Applications Office
Installation Indoor
Flow Rate 6.0 GPM
Color White
Condition New
Map Zone Northern Region
Map Zone Mid Region
Map Zone Southern Region

FAQs — Eccotemp 20HI Indoor 6.0 GPM Natural Gas Tankless Water Heater

Q: What is the max temperature my tankless water heater can achieve?

Answer: The temperature can vary based on the temperature of the incoming water. Each of our tankless water heaters offer at least a 35-40 degree F temperature rise based on the temperature of your incoming water. You will need to adjust the heater to the preferred temperature.

Q: Why do I need to clean my tankless water heater? Is it really necessary?

Answer: Yes. It is important to clean and descale your unit at least every 6 months to maintain its flawless performance. You can use our Eccotemp EZ Flush Descaler Kit. This will get rid of any water scale, lime, or rust deposit buildup in virtually any piece of water based equipment. Your water heater will run the risk of overheating and can deteriorate its effectiveness if you do not keep up with flushing your water heater.

Q: Can my tankless water heater freeze, even if it's installed indoors in a heated space?

Answer: It depends on the model. The L5, L7, L10, i12, FVI12, & iE Series do NOT come with any anti-freezing technology to help prevent freeze damage. This means that even if your i12 for example is installed indoors, it is not protected from freeze damage. The freeze damage can occur from cold air entering the internal chambers of the water heater via the venting. The 45H/HI, EL22/EL22i, 20H/20HI, all come with a built-in anti-freeze technology in the form of heating blocks. In order to ensure these blocks are doing their job, you must keep your water heater plugged in at all times. These blocks help prevent freeze damage to the heat exchanger, but is NOT a guarantee. Proper installation and maintenance must be followed to ensure that your water heater will last as long as possible.

Q: How do I check for Gas leaks?

Answer: After you have your gas connected to your unit, spray some soapy water or Windex sort of mixture on the connection and if you see bubbles, then you have a leak. If no bubbles, you are good to go with no leaks.

Q: Where’s the pilot light in the Eccotemp tankless water heaters? I can’t seem to find it.

Answer: Our products do not have pilot lights. There is an electronic ignition or battery powered ignition depending on the model of the water heater. The unit will ignite when there is hot water being requested of it and it will go out when you're done using the hot water.

Q: Can I convert my Natural Gas tankless water heater to use Liquid Propane instead?

Answer: No. Unfortunately, there are certain parts within each unit that are gas specific and not able to be converted to any other gas type.

Q: What are the clearances for the installation of my water heater?

Answer: The clearances vary depending on the model, but safely should be: At least 1-2 ft on top, 18" minimum at the bottom, 8-10" left and right, 6" from the wall, 2-3 ft from an open window

Q: What are the fittings made of on the water heaters?

Answer: The fittings are made of steel and all have external threads.

Q: Can I use PVC pipe for my venting?

Answer: Using any other material than what is recommended by CSA standards will void your warranty. You must use Stainless Steel Category II venting.