ProLine® XE Indoor 199,000 BTU Non-Condensing Natural Gas/Liquid Propane Tankless Water Heater

Model GTS-510U-I 200
4 out of 5 Customer Rating
ProLine® XE Indoor 199,000 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 10.0 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 Indoor 199,000 BTU Non-Condensing Natural Gas/Liquid Propane Tankless Water Heater
    Model GTS-510U-I 200
    4 out of 5 Customer Rating
    ProLine® XE Indoor 199,000 BTU Non-Condensing Natural Gas/Liquid Propane Tankless Water Heater is rated 4.8 out of 5 by 18.
    • y_2025, m_9, d_13, h_4
    • bvseo_bulk, prod_bvrr, vn_bulk_3.0.42
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    What to Expect from this Model
    modal-clock
    Unlimited
    single shower length
    modal-frame
    Unlimited
    back-to-back
    modal-frame
    2.3 showers
    at the same time
    modal-tank-capacity
    Unlimited
    max tub size
    modal-cost
    $248/year
    est. energy cost
    Based on location results for Columbus, OH 43215
    Product Details
    • Continuous Hot Water—Delivers continuous hot water at a flow rate of up to 10.0 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-510U-I Ultra Low-NOx Indoor Non-Condensing Tankless water heater uses up to 199,000 BTU/h of natural gas to deliver an endless supply of hot water for a 2.5 bath home in northern climates and a 4-bath home in southern climates (one shower head per bath).

      This model is suitable for commercial applications like beauty salons and small restaurants. A commercial-grade copper heat exchanger with a thicker drum means the GTS-510U-I can handle heavier residential usages, such as a combined space heating and domestic recirculation system.

      This model has a small footprint and is wall-mountable, providing a variety of installation options. The GTS-510U-I 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.

      For high-use applications, Easy-Link up to 4 units with the included communication cables. A Multi-Link controller (sold separately) can link up to 20 units.

      The GTS-510U-I 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
    199,000
    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
    INDOOR
    Limited Heat Exchanger Warranty 
    15 Years
    Max Flow Rate
    5 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
    40 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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