ProLine® XE Indoor 199,000 BTU Condensing Natural Gas Tankless Water Heater

Model GTS-540-NIH 100
5 out of 5 Customer Rating
ProLine® XE Indoor 199,000 BTU Condensing Natural Gas Tankless Water Heater is rated 4.6 out of 5 by 78.
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Installation Type
Fuel Source
Maximum BTU's

  • Continuous Hot Water—Delivers continuous hot water at a flow rate of up to 10.0 GPM
  • Optimized Heat Transfer—Primary commercial-grade copper heat exchanger is 25x better than stainless steel at heat transfer, stabilizing outgoing water temperatures quickly
  • Corrosion Protection—Secondary heat exchanger is made of 316L Stainless Steel to protect against corrosion

    • ProLine® XE Indoor 199,000 BTU Condensing Natural Gas Tankless Water Heater
    Model GTS-540-NIH 100
    5 out of 5 Customer Rating
    ProLine® XE Indoor 199,000 BTU Condensing Natural Gas Tankless Water Heater is rated 4.6 out of 5 by 78.
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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
    2.7 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
    $208/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 10.0 GPM
    • Optimized Heat Transfer—Primary commercial-grade copper heat exchanger is 25x better than stainless steel at heat transfer, stabilizing outgoing water temperatures quickly
    • Corrosion Protection—Secondary heat exchanger is made of 316L Stainless Steel to protect against corrosion
    • Energy Efficient—Highly-efficient condensing Ultra-Low Nox tankless water heater delivers up to .93 Uniform Energy Factor (UEF)
    • Flexible Venting—Flexible power direct vent design allows for venting up to 100 feet using either PVC, CPVC, polypropylene or ABS Pipe (solid core)
    • Shared Vent for Multiple Units—Common vent up to 8 units
    • Simple Control & Troubleshooting—Integrated temperature controls and advanced diagnostics make it easy to adjust settings and troubleshoot problems
    • Safety Features—Added safety features include a flame sensor, temperature monitoring, and an overheat cutoff fuse
    • Peace of Mind—Industry-leading 15-year limited warranty on heat exchanger in residential applications

      • The State ProLine® XE GTS-540-NIH Indoor Tankless High Efficiency Condensing water heater uses up to 199,000 BTU/hr of natural gas to deliver an endless supply of hot water for a 3-bath home in northern climates and a 4-bath home in southern climates (one shower head per bath).

      This Ultra-Low NOx model with condensing technology has a Uniform Energy Factor of 0.93 and meets the ASHRAE 90.1-2007 energy efficiency requirements, making it environmentally friendly and reducing operating costs.

      The GTS-540-NIH uses commercial grade copper alloy for the heat exchanger tubing and is suitable for heavier residential usages, such as domestic recirculation systems. Remote control is included as a standard feature on all outdoor models. Indoor models are certified up to a 10,100 ft. altitude.

      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-540-NIH tankless condensing 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
    0.93
    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
    5.8 GPM
    Minimum BTUs
    15,000
    Application
    RESIDENTIAL
    Shipping Height 
    33.25
    Shipping Length 
    21.75
    Shipping Width 
    15.625
    Side Loop
    No
    Dimension & Venting
    Type
    Water Heater
    Height
    23.63"
    Width
    17.75"
    Shipping Weight
    70 lbs
    Vent Type
    Power Direct Vent
    Find a Replacement
    Current Product
    Option 2
    ProLine® XE Indoor 199,000 BTU Condensing Natural Gas Tankless Water Heater
    Adapt™ SC Standard Condensing 199,000 BTU Natural Gas Tankless Water Heater
    GTS-540-NIH
    STM-199M-N
    current Product
    option 1
    Rebates up to $300 +
    Rebates up to $300 +
    Nominal Capacity
    1 Gallons
    Width
    17.75"
    17.12"
    Depth
    11.25"
    11.85"
    Height
    23.63"
    32.46"
    Shipping Weight
    70lbs
    93lbs
    Power Source
    GAS
    GAS
    Limited Tank Warranty
    0 Years
    0 Years
    Limited Parts Warranty
    5 Years
    5 Years
    Water Connection Location
    BOTTOM
    BOTTOM
    Water Connection Size
    0.75"
    Thermal Efficiency
    0%
    0%
    All Reviews for ProLine® XE Tankless High Efficiency Condensing (100 series)
    Rated 5 out of 5 by from great features I am very happy with this heater. Space saving, effective
    Date published: 2022-04-22
    Rated 5 out of 5 by from Unlimited amount of Hot Water We are pleased with the unlimited amount of hot water this device provides to us. We only wished the contractor had plumbed the house better as the kitchen is the farthest away from the water heater causing us to have to run the water for 3 minutes or more for it to get hot (an extreme waste of water). Great for long hot showers!
    Date published: 2022-04-18
    Rated 5 out of 5 by from Super upgrade It's only been 2 days and we are remarkably pleased and happy. Never will we rin out of hot water. Very efficient cost savings.
    Date published: 2022-03-26
    Rated 5 out of 5 by from Great energy saver I just had my tanked water heater replaced with this tankless model. It works great
    Date published: 2021-09-04
    Rated 5 out of 5 by from works very well. It seems to work very efficiently and is much less expensive to run
    Date published: 2021-05-22
    Rated 5 out of 5 by from Great support from the manufacturer Installed 23 months ago and just developed a water leak. Company stood by the product and we got a new one for free.
    Date published: 2021-04-14
    Rated 5 out of 5 by from Space saver This product helped me gain more space in my laundry room!
    Date published: 2021-03-27
    Rated 5 out of 5 by from Great unit Very happy so far with the tankless hot water heater
    Date published: 2021-02-28
    Rated 5 out of 5 by from This water heater was installed by the builder. I just moved in so honestly I haven't had time to know much about it. Hoping that it will be great. Can't answer the rest of these questions for the same reason. Just getting it registered has been a challenge.
    Date published: 2021-01-25
    Rated 5 out of 5 by from Works well, fast start up. Dependable. I originally installed this 2014 developed a heat exchanger leak 2020. States stood behind their product.
    Date published: 2020-12-23
    Rated 5 out of 5 by from Endless Hotwater Installed in our new home. Love the endless hot water
    Date published: 2020-11-29
    Rated 5 out of 5 by from Great System. This unit replaces another GTS-540-NIH that sprung a leak causing a ground fault. It was covered by warranty, so we replaced with same model. I like the on demand hot water. Never runs out.
    Date published: 2020-11-20
    Rated 5 out of 5 by from Endless hot water!!!! So far we have been very pleased with this product. It can even run off a generator if the power goes out simply by plugging it in.
    Date published: 2020-07-10
    Rated 5 out of 5 by from Efficient Small Footprint Efficient, takes up little space, clear instructions
    Date published: 2020-04-18
    Rated 5 out of 5 by from Easy to install . Small footprint. Excellent details in the installation manual. I'm on well water so the PP-AS20 PRODUCT PRESERVER and the 100112156 ISOLATION VALVE KIT was a no brainer and was suggested in the sale lit.
    Date published: 2020-01-20
    Rated 5 out of 5 by from Saves space - very quiet I had this professionally installed and it's very quiet, and heats up just a little faster than the large tank I had previously installed. Up to 140 degrees I can't even tell it's on. The endless supply allows me to fill the 1 person Jacuzzi now all at once and then shuts off after you turn the water handle to off. No more heating up for an what like seemed to be half an hour.
    Date published: 2019-12-13
    Rated 5 out of 5 by from Works very well! The water is always hot. We’ve had this water heater since September. It works very well. We can’t wait to see the impact on our gas bill.
    Date published: 2019-10-11
    Rated 5 out of 5 by from GTS-540-NIH, it is very compact and pretty look I bought this GTS-540-NIH and installed on 9/12/2019 by Climate Zone. It is very compact, light and wall mountable. It ran very quiet and I loved it.
    Date published: 2019-09-15
    Rated 5 out of 5 by from Excellent features We bought this a month ago and really enjoy the continuous hot water. Can’t wait to see the savings.
    Date published: 2019-03-27
    Rated 5 out of 5 by from Efficient I have had this product for well over a year and it runs perfectly. It supplies my whole house with plenty of hot water. Worth every penny!
    Date published: 2019-03-04
    Rated 5 out of 5 by from No struggle keeping up We bought a tankless 15 years ago when they were new and we had nothing but trouble with it. Now we bought a new one with new technology and keeps up with our large family very well. We never have hot water issues.
    Date published: 2019-01-03
    Rated 5 out of 5 by from Great replacement system Replaced a 75 gallon tank system with the tankless and so far pleased with the result.
    Date published: 2018-12-08
    Rated 5 out of 5 by from Fast, consistent hot water Hot water almost as quick as my tank heater. Installation is a bit expensive, but I think it will be a better investment.
    Date published: 2018-10-18
    Rated 5 out of 5 by from Works great The old one was hard to regulate the water temp and took a very long time to warm up. This unit warms up quicker and is very easy to regulate the temperature.
    Date published: 2018-07-05
    Rated 5 out of 5 by from State Takagi Tankless Water Heater VERY happy with purchase. Replaced tanked water heater and could not be happier. NO issues with endless hot water and saves on gas bill in
    Date published: 2018-03-24
    Rated 5 out of 5 by from Great product Have been using the heater for three months now and it’s is perfect. Installed it myself (professional contractor), and it was straight forward, well designed, and solid. I would and have recommended this water heater. The only thing I highly recommend is a recirculating pump/ line, I will be adding one to my system, I would have done it during install but it was an emergency job as my old 50 gallon tank burst.
    Date published: 2018-02-12
    Rated 5 out of 5 by from Great water heater This is the second State WH we have purchased. We installed one in the house we previously owned and knew when we built this house we would install another one.
    Date published: 2018-01-24
    Rated 5 out of 5 by from using friendly and easy I brought one before but found out some failure after one year now with new free replacement. this product user friendly and easy. gas saving too. For me it is a very good product.
    Date published: 2018-01-08
    Rated 5 out of 5 by from Too Early to tell. Just had this Tankless Water Heater (Propane GTS 540-PEH) installed by an experienced plumber. It is doing a great job. It was just installed 4 days ago. My previous tankless water heater was also a Takagi essentially same model but 3 generations back. It was a relatively good water heater with occasional problems (none of which required any major expense). It was 5 to 6 years old and had only been serviced 6 months before. One of the sensors had gone bad, but with the labor cost for repairs and possible small leak I decided to change to a newer and more efficient model, The GTS 540-PEH by State which is a Takagi model and the plumber who installed it came highly recommended. A little pricy but I hope that it will turn out to be well worth it. The 15 year limited warranty is nice. I will be happy if it lasts 10 years without any trouble. By the way, I am using this water heater in a personal home with a five bedroom, 4 baths, in central Florida. We do a lot of cloths washing. I will provide additional comments in a year or two regarding this model.
    Date published: 2017-11-27
    Rated 5 out of 5 by from Workhorse Just installed last week. This thing provides a ton of heat output. One night it started making an intermittent humming resonance type noise that was a little annoying. It may be related to elevation and air intake - contractor coming back to take a look.
    Date published: 2017-11-12
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