A.O. Smith
ATHR-199M Adapt™ Premium Condensing Ultra-Low Nox 199,000 BTU/hr Natural Gas Tankless Water Heater
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- Delivering robust, on-demand performance, these high-efficiency heaters install in practically any residential setting. The single stainless steel, heavy-duty heat exchanger design is more resilient to scale buildup and corrosion and when coupled with X3 Scale Prevention Technology (not included), there is zero lifetime descaling maintenance required.
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- Integrated Recirculation Pump
- Field convertible from Natural Gas to Liquid Propane, Kit Included
- 22:1 Turndown Ratio
- Max flow rate 10.5 GPM, 0.4 GPM activation
- 1/2" Gas Line
- Venting Flexibility 2" up to 75' & 3" up to 150'
- **Outdoor Vent Cap Kit Required, Kit Sold Separately
- Flow Rate10.5 gpm MaxFuel TypeNatural GasHeating Capacity199,000 BTU/hrIndoor / OutdoorIndoor / OutdoorUltra Low NOxYesVent TypePower DirectDimensions33.8 in H x 16.1 in D x 16.5 in WManufacturerA.O. SmithManufacturer #100374799SeriesAdaptVoltage Rating120 VWeight104 lb