ProLine® XE Outdoor 190,000 BTU Non-Condensing Natural Gas/Liquid Propane Tankless Water Heater

Model GTS-310U-E 200
3.4 out of 5 Customer Rating
ProLine® XE Outdoor 190,000 BTU Non-Condensing Natural Gas/Liquid Propane Tankless Water Heater is rated 4.8 out of 5 by 18.
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Installation Type
Maximum BTU's

  • Continuous Hot Water—Delivers continuous hot water at a flow rate of up to 8.0 GPM
  • Space-Saving Design—Wall-mount design saves valuable space and allows for additional storage and flexibility
  • Optimized Heat Transfer—Commercial-grade copper heat exchanger is 25x better than stainless steel at heat transfer, stabilizing outgoing water temperatures quickly

    • ProLine® XE Outdoor 190,000 BTU Non-Condensing Natural Gas/Liquid Propane Tankless Water Heater
    Model GTS-310U-E 200
    3.4 out of 5 Customer Rating
    ProLine® XE Outdoor 190,000 BTU Non-Condensing Natural Gas/Liquid Propane Tankless Water Heater is rated 4.8 out of 5 by 18.
    • y_2025, m_9, d_16, h_9
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    What to Expect from this Model
    modal-clock
    tooltip
    Number of minutes you can enjoy a shower before running out of hot water. Assumes a 2.1 GPM flow rate
    Unlimited
    single shower length
    modal-frame
    tooltip
    Number of back-to-back showers you can take without running out of hot water. Assumes a 2.1 GPM flow rate and an 8 minute shower length
    Unlimited
    back-to-back
    modal-frame
    tooltip
    Number of showers you can take at the same time without running out of hot water. Assumes a 2.1 GPM flow rate and an 8 minute shower length
    2.2 showers
    at the same time
    modal-tank-capacity
    tooltip
    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
    Unlimited
    max tub size
    modal-cost
    tooltip
    The estimated annual cost to operate this water heater in your location
    $236/year
    est. energy cost
    Based on location results for Columbus, OH 43215
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    Edit Location / Advanced Settings
    Product Details
    • Continuous Hot Water—Delivers continuous hot water at a flow rate of up to 8.0 GPM
    • Space-Saving Design—Wall-mount design saves valuable space and allows for additional storage and flexibility
    • Optimized Heat Transfer—Commercial-grade copper heat exchanger is 25x better than stainless steel at heat transfer, stabilizing outgoing water temperatures quickly
    • Converts to A Different Fuel Source—Easily convertible from natural gas to propane with supplied kit
    • Energy Efficient—Highly-efficient condensing Ultra-Low Nox tankless water heater delivers up to .82 Uniform Energy Factor (UEF)
    • Longer Vent When Needed—Vents up to 60 feet using 4” Category III stainless steel
    • Simple Control & Troubleshooting—Integrated temperature controls and advanced diagnostics make it easy to adjust settings and troubleshoot problems
    • Safety Features—Added safety protection from built-in freeze protection, overheat cut-off fuse, and air-fuel ratio (AFR) sensor
    • Peace of Mind—Industry-leading 15-year limited warranty on heat exchanger in residential applications

      • The State GTS-310U-E Ultra Low-NOx Outdoor Non-Condensing Tankless water heater uses up to 190,000 BTU/h of natural gas to deliver an endless supply of hot water for a 2.5-bath home in northern climates and a 3.5-bath home in southern climates (one shower head per bath).

      This model has a small footprint and is wall-mountable, providing a variety of installation options. The GTS-310U-E complies with Ultra-Low NOx regulations, meets the energy efficiency requirements of ASHRAE 90.1-b 1992, and has a Uniform Energy Factor of 0.82.

      The GTS-310U-E tankless water heater provides years of hot water through innovation and quality and is backed by an industry-leading 15-year limited warranty.

    Specifications
    Tech Specs
    UEF
    0.81
    Maximum BTUs
    190,000
    Power Source
    GAS
    Limited Parts Warranty
    5 Years
    Water Connection Location
    BOTTOM
    Emissions
    Ultra-Low NOx
    ASME Certified
    No
    Destination Country
    US
    Digital Display
    Yes
    Fuel Source
    NATURAL
    Installation Type
    OUTDOOR
    Limited Heat Exchanger Warranty 
    15 Years
    Max Flow Rate
    4.8 GPM
    Minimum BTUs
    15,000
    Application
    RESIDENTIAL
    Shipping Height 
    28
    Shipping Length 
    16.625
    Shipping Width 
    12.375
    Side Loop
    No
    Dimension & Venting
    Type
    Water Heater
    Height
    20.5"
    Width
    13.75"
    Shipping Weight
    39 lbs
    Vent Type
    Direct Vent
    All Reviews for Tankless Ultra Low Nox Non Condensing Tankless Non-Condensing Ultra-Low Nox (200 series)
    Rated 5 out of 5 by from no tank Just bought unit today seems to work unit had great review from people who had one
    Date published: 2024-02-09
    Rated 5 out of 5 by from Great Product I bought this month ago and I am very happy with product. Only thing not positive is you can not increase temperature more then 120 F.
    Date published: 2024-01-18
    Rated 5 out of 5 by from Works very well I bought this about a month ago so far no complaints from me or my child
    Date published: 2023-05-30
    Rated 5 out of 5 by from On my new house and it’s great for water temperature
    Date published: 2022-06-01
    Rated 5 out of 5 by from easy to operate! Got this unit under warranty to replace the unit we had before! Love this unit; so easy to set up and delivers ample hot water!
    Date published: 2022-04-11
    Rated 5 out of 5 by from Nice Digital Readout Works as described! I even get hot water quicker than the other one
    Date published: 2021-05-10
    Rated 5 out of 5 by from Best tankless unit on the market I’ve had Rinnai and the others but this unit is the best built overall and much cheaper also. I haven’t had a single issue in 6 years!
    Date published: 2021-05-03
    Rated 5 out of 5 by from Not sure yet but had a Takagi hot water heater since 2005 with no problems. The circuit board went out and they did not make it anymore so I needed to replace the unit. I purchased this because it it from the same Manufacturer Takagi. hopefully it will last as long.
    Date published: 2021-01-31
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