A.O. Smith ATO-140H-N 120,000 BTU Condensing Ultra-Low NOx Outdoor Tankless Water Heater (NG)

Product Description

The A.O. SMITH ATO-140H-N tankless water heater uses up to 120,000 BTUs of natural gas to deliver a max flow rate of 6.6 GPM. It features high efficiency Ultra-Low NOx condensing technology allowing for the use of 3 PVC venting and has 0 clearance to combustibles. It utilizes condensing technology to achieve a Uniform Energy Factor of 0.91.

• Continuous flow rate up to 6.6 GPM
• Wall-mount design saves valuable space and allows for additional storage and flexibility
• Primary commercial-grade copper heat exchanger is 25x better than stainless steel at heat transfer, stabilizing outgoing water temperatures quicker

Product Highlights

This A. O. Smith tankless water heater is designed for outdoor installation and provides a continuous flow of hot water on demand.

Product Information

Standard Information

• Brand: A.O. SMITH
• Manufacturer Part Number: ATO-140H-N
• Country of Origin: US

Technical Specifications

• Product Type: Tankless Heater
• Type: Condensing
• Fuel Type: Natural Gas
• Inlet Gas Pressure: 4.0-10.5"W.C
• Installation Type: Outdoor Only
• Gas Connection: 1/2"
• Water Connection: 3/4"
• Gas Input: 15000 to 120000 BTU/h
• Energy Factor: 0.93
• Voltage: 120v
• Max Flow (GPM): 6.6
• Height (Inches): 22.875"
• Width (Inches): 13-7/8"
• Depth (Inches): 10-13/16"
• BTU (Max): 120000
• BTU (Min): 15000
• Vent Type: Outdoor (No Venting)
• Application: Residential
• Flow Rate at 40F Temp Rise (GPM): 5.4
• Flow Rate at 50F Temp Rise (GPM): 4.4
• Flow Rate at 60F Temp Rise (GPM): 3.8
• Flow Rate at 70F Temp Rise (GPM): 3.2
• UEF: 0.91
• Maximum BTUs: 120,000
• Power Source: GAS
• Water Connection Location: BOTTOM
• Emissions: Ultra-Low NOx
• ASME Certified: No
• Fuel Source: NATURAL
• GPM (@67 F Temp Rise): 3.5 GPM
• Minimum BTUs: 15,000
• Side Loop: No
• Water Pressure (Min): 15 PSI
• Water Pressure (Max): 150 PSI
• Temperature (Max): 140 F
• Activation GPM: 0.5
• Duct Size: 3" Round, 4" Round
• Flow Rate (GPM): 6.6
• Maximum Flow Rate: 6.6 GPM
• Minimum Flow Rate: 0.5 GPM
• Minimum Gas Input: 15000
• Uniform Energy Factor (UEF): 0.93
• Vent Maximum Run: 1200, 840 in.
• Direct Vent: Yes
• Display Type: Digital
• Heating Technology: Condensing
• Natural Gas Input (Min): 4.0
• Water Connection Type: NPT
• Altitude Certification: 6000 ft.
• Condensing: Yes
• Default Temperature: 120 F
• Ignition Type: Electric
• Max BTU Input: 120000
• NG Energy Factor: .91
• Hardwired: Yes
• ADA: No
• ANSI Certification: Z21.10.3
• Certifications: AHRI, ANSI, CSA
• Energy Star: No
• Low Lead Compliant: Yes
• Outdoor Approved: Yes
• Product Variation: Whole House Water Heater
• SCAQMD Compliant: Yes
• Title 20 Compliant: Yes
• Uniform Energy Factor: 0.93
• Commercial/Residential/Dual: Commercial/Residential
• Flow Rate: 6.6 gpm
• Heating Capacity: 120000 Btu/hr
• Series: ATO-140H
• Ultra Low NOx: Yes
• Vent Size: 3 in, 4 in