AO Smith 8 GPM 180,000 BTU 120 Volt Residential Outdoor Natural Gas Tankless Water Heater with Ultra-Low Nox and X3 Scale Prevention Technology
Model: ATO-340HX3-N|Item: bci4834288
Details
A.O. Smith continues to lead the way in residential water heating with close to 70 years of innovative hot water solutions. The ATO-340HX3-N condensing gas tankless water heater features X3 Scale Prevention Technology to last three times longer than other tankless models without X3 Technology. Complies with Ultra-Low NOx regulations and utilizes commercial-grade copper alloy for the heat exchanger tubing and are approved to work with an external recirculation pump and cross-over valve. Making this one of the most efficient heaters on the market.
Product Information:
- X3 Scale Prevention Technology: With the patent pending technology, no annual descaling is required. With no scale buildup means the heater maintains like-new performance longer.
- Heavy Duty Heat Exchanger: The primary heat exchanger is built out of copper, offering better heat transfer than stainless steel and designed to be more resilient against corrosion. A.O. Smith water heaters are built to last and save you money in the process.
- Multiple Safety Features: A.O. Smith water heaters come with a long list of safety features standard. These include built-in freeze protection, overheat cutoff fuse, exhaust & water temperature safety control and an Air-Fuel Ratio (AFR) Sensor.
- Recirc Capable: Tankless water heaters with X3 Technology are approved to work with an external recirculation pump and cross over valve.
- Ultra Low-NOx Emissions: This A.O. Smith tankless water heater is designed to qualify for the most stringent Low-NOx standards. These standards coincide with SCAQMD rules and other air quality management districts.
- Product Includes
- Installation manual and owner's guide
- Temperature remote controller kit
- X3 cartridge
Features:
- Never run out of water again with a steady 8 GPM flow rate
- This product is Energy Star certified with a Uniform Energy Factor of 0.94
- Covered under a 15-year heat exchanger warranty
- Covered under a 5 year parts manufacturer warranty
Specifications:
- Width: 17-3/4"
- Height: 23-5/8"
- Depth: 11-1/4"
- Fuel Type: Natural Gas
- Gas Connection: 3/4"
- Connection Size: 3/4"
- Voltage: 120V
Dimensions and Measurements
Depth | 11.25 in. |
Duct Size | 3" Round, 4" Round |
Gas Connection | 3/4" |
Height | 23.625 in. |
Maximum Flow Rate | 8 GPM |
Maximum Gas Input | 180000 |
Minimum Flow Rate | 4.3 GPM |
Minimum Gas Input | 15000 |
Product Weight | 59 lbs. |
Water Connection | 3/4" |
Width | 17.75 in. |
Dimensions and Measurements
Depth | 11.25 in. |
Duct Size | 3" Round, 4" Round |
Gas Connection | 3/4" |
Height | 23.625 in. |
Maximum Flow Rate | 8 GPM |
Maximum Gas Input | 180000 |
Minimum Flow Rate | 4.3 GPM |
Minimum Gas Input | 15000 |
Product Weight | 59 lbs. |
Water Connection | 3/4" |
Width | 17.75 in. |
Included Components
Includes Remote | Yes |
Included Components
Includes Remote | Yes |
Characteristics and Features
Heating Technology | Condensing |
Indoor Installation | No |
Vent Type | Vent Free |
Characteristics and Features
Heating Technology | Condensing |
Indoor Installation | No |
Vent Type | Vent Free |
Electrical and Operational Information
Altitude Certification | 6000 ft. |
Condensing | Yes |
Energy Factor | 0.95 |
Frequency | 60 Hertz |
Fuel Type | Natural Gas |
Ignition Type | Electric |
Max BTU Input | 180000 |
Voltage | 120 |
Electrical and Operational Information
Altitude Certification | 6000 ft. |
Condensing | Yes |
Energy Factor | 0.95 |
Frequency | 60 Hertz |
Fuel Type | Natural Gas |
Ignition Type | Electric |
Max BTU Input | 180000 |
Voltage | 120 |
Warranty and Product Information
Approved for Commercial Use | No |
Certifications | AHRI, ANSI, CSA |
Collection | ProLine XE |
Country Of Origin | USA |
Energy Star | Yes |
Heat Exchanger Warranty | 15-Years |
Made in America | Yes |
Manufacturer Warranty | 5 Year Parts |
Outdoor Approved | Yes |
Product Variation | Whole House Water Heater |
SCAQMD Compliant | Yes |
Title 20 Compliant | No |
Uniform Energy Factor | 0.94 |
Warranty and Product Information
Approved for Commercial Use | No |
Certifications | AHRI, ANSI, CSA |
Collection | ProLine XE |
Country Of Origin | USA |
Energy Star | Yes |
Heat Exchanger Warranty | 15-Years |
Made in America | Yes |
Manufacturer Warranty | 5 Year Parts |
Outdoor Approved | Yes |
Product Variation | Whole House Water Heater |
SCAQMD Compliant | Yes |
Title 20 Compliant | No |
Uniform Energy Factor | 0.94 |

