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Tankless Water Heater Non-Condensing Ultra-Low NOx Indoor 190,000 BTU Natural Gas/Propane

Tankless Water Heater Non-Condensing Ultra-Low NOx Indoor 190,000 BTU Natural Gas/Propane

Tankless Water Heater Non-Condensing Ultra-Low NOx Indoor 190,000 BTU Natural Gas/Propane

Model # GTS-310U-I
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State products are available through independent plumbing contractors.
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Product Description

The 310U Series is great for two bath homes in cold climates. The 310U features a max flow rate of 8.0 gallons per minute providing enough hot water to run three showers at the same time. The design allows for a variety of installation options. Complies with Ultra-Low NOx regulations and meets energy efficiency requirements of ASHRAE 90.1b-1992.

The GTS-310U-I tankless water heater uses up to 190,000 BTU/h of natural gas/liquid propane to deliver an endless supply of hot water for a 2.5 bath home in northern climates and up to a 3.5 bath home in southern climates (one shower head per bath). The GTS-310U-I is ENERGY STAR® qualified with a Uniform Energy Factor of 0.81. With an industry leading 15-year limited warranty, the GTS-310U-I tankless water heater provides years of hot water through innovation and quality.

Where to Buy

Enter your city and state or zip code below to find a local installer.


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State products are available through independent plumbing contractors.
Enter your city and state or zip code below to find a local installer.


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Certifications

15

year

limited warranty

0.81

Uniform Energy Factor

CSA International Low Lead Content Certification in compliance with U.S. and Canadian safety standards on gas components
AHRI Air-Conditioning, Heating and Refrigeration Institute
CSA International Design Certification The CSA Blue Star indicates the product is certified to applicable U.S. standards for appliances using gas or other petroleum fuel
  • Emissions: Ultra-Low NOx
  • Maximum BTU/h: 190,000
  • UEF 0.81
  • Minimum BTU/h: 15,000
  • Limited Heat Exchanger Warranty: 15 Years
  • Limited Parts Warranty: 5 Years
  • Water Connection Location: Bottom
  • Water Connection Size: 3/4"
  • Heat Exchanger: Copper
  • Voltage: 120
  • Digital Display: Yes
  • Technology: Non-Condensing
  • Height: 20 1/2"
  • Width: 13 3/4"
  • Depth: 10"
  • Product Weight: 38 lbs/17 kg
  • Shipping Weight: 39
  • Vent Type: Direct Vent
  • Vent Length: 60 feet at 4 diameter

FIELD CONVERTIBLE FROM NATURAL GAS TO PROPANE

Easily convertible from natural gas to propane with supplied kit..

Copper Heat Exchanger

25x better heat transfer than stainless steel thus stabilizing outgoing water temperature quicker and reducing pressure drop across the heat exchanger.

Safety Features

Includes freeze, overheat, surge protection and troubleshooting diagnostic codes.

Space Savings

State tankless water heaters take up much less space that your conventional tank-style water heater. With no tank to steal valuable storage space, our wall-mount design allows for additional storage and flexibility.


How long would you like to enjoy a shower?

Fairfield, Connecticut 06828

Change Location or Advanced Settings
Number of minutes you can enjoy a shower before running out of hot water. Assumes a 2.2 GPM flow rate.

Need to view or change our assumptions? Access the advanced settings.
minutes

Single
Shower Length

Number of minutes you can enjoy a shower before running out of hot water. Assumes a 2.2 GPM flow rate.

Need to view or change our assumptions? Access the advanced settings.

Close
Number of back-to-back showers you can take without running out of hot water. Assumes a 2.2 GPM flow rate and an 8 minute shower length.

Need to view or change our assumptions? Access the advanced settings.
Showers

Back to
Back

Number of back-to-back showers you can take without running out of hot water. Assumes a 2.2 GPM flow rate and an 8 minute shower length.

Need to view or change our assumptions? Access the advanced settings.

Close
Number of showers you can take at the same time without running out of hot water.Assumes a 2.2 GPM flow rate and an 8 minute shower length.

Need to view or change our assumptions? Access the advanced settings.
Showers

 At the Same Time

Number of showers you can take at the same time without running out of hot water.Assumes a 2.2 GPM flow rate and an 8 minute shower length.

Need to view or change our assumptions? Access the advanced settings.

Close
Biggest tub this water heater will fill without running out of hot water. Assumes a 5.0 GPM flow rate, and a 67% fill level.

Need to view or change our assumptions? Access the advanced settings.
gallons

Maximum Tub Size

Biggest tub this water heater will fill without running out of hot water. Assumes a 5.0 GPM flow rate, and a 67% fill level.

Need to view or change our assumptions? Access the advanced settings.

Close
Number of minutes required to fill a 55 gallon tub. Assumes a 5.0 GPM flow rate and a 67% fill level.

Need to view or change our assumptions? Access the advanced settings.
minutes

Time to Fill Tub

Number of minutes required to fill a 55 gallon tub. Assumes a 5.0 GPM flow rate and a 67% fill level.

Need to view or change our assumptions? Access the advanced settings.

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The estimated annual cost to operate this water heater in Fairfield, Connecticut.

Need to view or change our assumptions? Access the advanced settings.
$ Dollars

Estimated Energy Cost

The estimated annual cost to operate this water heater in Fairfield, Connecticut.

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Close

Many factors affect the actual performance of a water heater. This represents our closest approximation of your likely experience with this water heater in Fairfield, Connecticut, but actual performance may vary depending on factors beyond our ability to control or estimate. To view or adjust our assumptions of the most common factors that impact this product’s performance in Fairfield, Connecticut, please view the advanced settings. *Annual Estimated energy costs are estimated calculated from the energy efficiency of each water heater, your household’s estimated hot water usage & set temperature, the average groundwater temperature for your location, and residential energy prices for your location as reported by the Department of Energy and the Energy Information Administration.

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Product Features & Options

FIELD CONVERTIBLE FROM NATURAL GAS TO PROPANE

Easily convertible from natural gas to propane with supplied kit..

Copper Heat Exchanger

25x better heat transfer than stainless steel thus stabilizing outgoing water temperature quicker and reducing pressure drop across the heat exchanger.

Safety Features

Includes freeze, overheat, surge protection and troubleshooting diagnostic codes.

Space Savings

State tankless water heaters take up much less space that your conventional tank-style water heater. With no tank to steal valuable storage space, our wall-mount design allows for additional storage and flexibility.


Emissions: Ultra-Low NOx
Maximum BTU/h: 190,000
UEF 0.81
Minimum BTU/h: 15,000
Limited Heat Exchanger Warranty: 15 Years
Limited Parts Warranty: 5 Years
Water Connection Location: Bottom
Water Connection Size: 3/4"
Heat Exchanger: Copper
Voltage: 120
Digital Display: Yes
Technology: Non-Condensing
Height: 20 1/2"
Width: 13 3/4"
Depth: 10"
Product Weight: 38 lbs/17 kg
Shipping Weight: 39
Vent Type: Direct Vent
Vent Length: 60 feet at 4 diameter

Certifications

15

year

limited warranty

0.81

Uniform Energy Factor

CSA International Low Lead Content Certification in compliance with U.S. and Canadian safety standards on gas components
AHRI Air-Conditioning, Heating and Refrigeration Institute
CSA International Design Certification The CSA Blue Star indicates the product is certified to applicable U.S. standards for appliances using gas or other petroleum fuel
place

Where to Buy

A. O. Smith water heaters are available through your local plumbing professional.

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