Gas Tankless Water Heaters

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Gas tankless water heaters can use either natural gas or liquid propane for their fuel source and be installed either indoors or outdoors. If you are looking for this type of versatility, shop our wide selection of gas tankless water heaters from the top brands and find the perfect match today.

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Brand

Rinnai (43)

Takagi (36)

Rheem Tankless (33)

Noritz (50)

A.O. Smith (39)

Bosch Thermotechnology (6)

State Water Heaters (12)

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Fuel Type

To create heat, some form of fuel is required. Fuel Type specifies what the product uses as an input to create heat.

Liquid Propane (99)

Natural Gas (120)

Maximum Input Capacity (BTU)

The Maximum Input Capacity describes how quickly the appliance will use fuel when delivering it's maximum capacity. The units may change depending on the fuel being used.

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Uniform Energy Factor

Uniform Energy Factor (UEF) is a measurement of water heater energy efficiency. The higher the energy factor, the more efficient the water heater.

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0.82 (13)

0.83 (2)

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0.95 (31)

0.96 (7)

0.97 (9)

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Vent Type

Products that use combustion (burning) of fuel to create heat also create potentially dangerous gasses that need to be exhausted (AKA "Vented"). Depending on the product, venting can be done via a chimney, through a side wall, or use a second vent to provide fresh air to the appliance.

Concentric Vent (16)

Direct Vent (102)

Outdoor (No Venting) (99)

Power Vent (2)

Combustion Type

Condensing appliances use leftover thermal energy from combustion gases to heat water in a secondary heat exchanger, resulting in higher efficiency and lower exhaust temperature.

Condensing (157)

Non-Condensing (62)

Installation Location

Indoor (106)

Indoor / Outdoor (10)

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Gas Conversion Kit

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Sensei (19)

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Value Series (12)

valueSolutions (4)

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Ultra Low NOx Emissions

NOx is a byproduct of the combustion process, and it's output is regulated in some jurisdictions. Many regulators mirror SCAQMD rules, which regulate air quality for some parts of Southern California. Ultra Low NOx appliances emit less than 10-14 ng/J (nanogram per Joule) of NOx. Learn More

No (4)

Yes (208)

Flow Rate at 40F Temperature Rise (GPM)

Flow rate measures how much hot water your heater can deliver. Click Learn More to determine the appropriate temperature rise to use based on your location. Learn More

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5 (22)

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7 (40)

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Flow Rate at 50F Temperature Rise (GPM)

Flow rate measures how much hot water your heater can deliver. Click Learn More to determine the appropriate temperature rise to use based on your location. Learn More

3 (4)

4 (26)

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7 (53)

8 (2)

Flow Rate at 60F Temperature Rise (GPM)

Flow rate measures how much hot water your heater can deliver. Click Learn More to determine the appropriate temperature rise to use based on your location. Learn More

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4 (20)

5 (116)

6 (55)

Flow Rate at 70F Temperature Rise (GPM)

Flow rate measures how much hot water your heater can deliver. Click Learn More to determine the appropriate temperature rise to use based on your location. Learn More

2 (4)

3 (37)

4 (120)

5 (56)

Includes Pump

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Yes (30)

Price

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800 - 999 (28)

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1400 - 1599 (57)

1600 - 1799 (12)

1800 - 1999 (17)

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2200 - 2399 (5)

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Voltage (Volts)

120 (186)

Rinnai Sensei™ - RSC199 - 6.4 GPM at 60° F Rise - 0.93 UEF - Propane Tankless Water Heater - Direct Vent

Model: RSC199IP

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$2,244.00

In-Stock

Free Shipping

*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges may apply, see our full shipping policy for more details.

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Save 2% instantly by using our convenient "e-check" option or by simply mailing us a paper check. Yes, your order will be delayed slightly (5 business days). But, if you can wait, the savings are significant.