State GTS-510C-NI (Takagi TK-510C, AO Smith ATI-510C, Reliance TS-510C)
Tankless Non-condensing Water Heater Concentric Vent 199,000 BTU Natural Gas/Propane
The 110C, 310C and 510C series tankless water heater are fully modulating, gas fired, with sealed combustion and power vented flue. It is optimized for residential hot water systems. Either directly or indirectly, this heater can be used with water storage tanks, recirculation systems, or combined domestic hot water and space heating applications.
The GTS-510C-NI tankless water heater delivers a maximum flow rate of 10 GPM. However, please refer to the Flow Rate vs. Temp. Rise graph below to determine how much hot water you will get. It may not be 10 GPM under all circumstances.
This heater uses up to 199,000 BTUs of natural gas or liquid propane. It is non-condensing with an Energy Factor of 0.82. The venting design is concentric and meets California and Texas Ultra-Low NOx emission requirements. It features a long, 15-year limited warranty on the heat exchanger for residential installations, and a 10-year limited warranty with commercial installations. 5-year limited warranty on all parts.
• Easily converted from natural gas to propane with included kit
• Built-in protection from freezing
State/A.O. Smith/Takagi/American/Reliance brands Tankless Non-Condensing Water Heaters
With innovative designs and stronger components, these non-condensing water heaters are more durable and longer-lasting. Count on AO Smith's brands of non-condensing tankless water heaters for expertise and innovation.
Certified by CSA according to ANSI Z21.10.3. Minimum energy factor of 0.82. Complies with the energy efficiency requirements of the US Department of Energy, ASHRAE 90.1, SCAQMD Rule 1146.2 and some other air quality districts with contiguous requirements for low NOx emissions (14 ng/J or 20 ppm). Certified to NSF 5 standards.
Specifications of Indoor Models
Operating water pressure range is 15 to 150 psi. 40 psi (and above) is recommended to achieve the maximum flow rate.
1For Propane, the minimum inlet gas pressure 8.0 inches of W.C. and maximum of 14.0 inches of W.C.
Electrical: For flame ignition, the heater uses a 120 V/60 Hz power source with a standard appliance power cord. Max amps including freeze protection mode: 0.83 Amps
Certified from sea level up to 10,100 ft. elevations.
Complies with lead-free standards.
Venting and combustion
This heater uses the Takagi Proprietary APNC35 Concentric Vent Design which allows for an extremely long maximum venting length of 43 feet and up to 4 elbows. This power direct vent system can be installed with vertical or horizontal vent termination installation. Venting instructions:
More Technical Details
This is a fully modulating, non-condensing, on-demand gas fired tankless water heater. It features a maximum input rating of 199,000 Btu/h, and uses either natural gas (NG) or propane (LP). For LPG, the heater can be changed in the field using the included conversion kit. The heater has an integrated temperature controller that provides diagnostic information, allows the user to set an output temperature, and shows fault history.
This heater uses a commercial-grade copper alloy, a quick release bronze or brass waterways, and a fin tube heat exchanger. The heater is controlled by a solid-state printed circuit board with the following:
• Thermistors that monitor water temperature
For additional water heating capacity, using the Easy-Link system up to four heaters can be connected. The Easy-Link controls can be built into circuit board to eliminate the need for external controls. The linking control wire is provided with the heater. The MultiUnit Controller (part number 008300005) can manifold together 5 to 20 heaters. Both the Easy-Link and Multi-Unit Controller will modulate the system for the highest performance. It rotates the priority heater every 12 hours or 100 starts to balance the duty and cycle operation.
— indicates a set temperature of 125°F (52oC) or lower
FAQ (Frequently Asked Question)
Q: Why does this product title say "State GTS-510C-NI (Takagi TK-510C, AO Smith ATI-510C, Reliance TS-510C)"?
• Isolation Valve Kit (item number 9007604005)