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A.O. Smith ATO-540H - Residential 199,000 BTU - Natural Gas Tankless Water Heater - Outdoor
Model:
ATO-540H-N
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Recommended Accessories
Expert Recommended Accessories
Selected by Ken, our Expert
Required Accessories
9
These accessories are required to properly setup/install this product.
Optional Accessories
10
Features
Fuel
Natural Gas
Location
Outdoor
# of Showers
3.0
UEF
0.95
Energy Star Certification
Yes
Product Video Disclaimer: "PED is not responsible for any variances from the product in this video and the item you purchase. Please review all product specs prior to purchase."
- High Efficiency Condensing Technology
- The ATO-540H-N features the latest in water heating condensing technology. This means that the unit can deliver some of the highest efficiency standards on the market, keeping dollars in your pocket.
- Ultra Low-NOx Emissions
- The ATO-540H-N is designed to qualify for the most stringent Low-NOx standards. These standards coincide with SCAQMD rules and other air quality management districts.
- 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
- ATO models come with a long list of safety features standard. These include: built in freeze protection, manual reset hi limit, an overheat cutoff fuse, inlet and outlet thermistors to monitor temperatures, and a built-in flame sensor.
- Space Saving Design
- A.O. Smith tankless heaters take up less space than their conventional counterparts. The convenient wall mount design means they can fit in nearly any outdoor wall layout and offer additional flexibility.
A.O. Smith continues to lead the way in residential water heating with close to 70 years of innovative hot water solutions. The ATO-540H-N is A.O. Smith's high efficiency, Ultra-Low NOx outdoor model, it keeps emissions low by featuring the latest in water heating technology. Switching on when a hot water tap is opened, a built in temperature sensor helps to maintain hot water within a one degree set point during use, and the system automatically shuts off when the tap is closed saving you energy. An included wall mount remote controller gives you simple and complete control over your water heater.
California residents see
WARNING: This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm..
For more information go to: www.p65Warnings.ca.gov
Specifications
ATO-540H-N
Overview
Product Category
Water Heater - Tankless
UPC
671657140953
General Information
Type
Tankless Water Heater
Product Line
ProLine
Product Category
Water Heater - Tankless
Medium
Medium
Medium refers to the substance that carries heat through the heating system. Systems are either designed to use either Hot Water or Steam as a medium, and components are usually specific to one or the other.
Hot Water
Heat Exchanger Material
Copper/Stainless
Fuel Type
Fuel Type
To create heat, some form of fuel is required. Fuel Type specifies what the product uses as an input to create heat.
Natural Gas
Combustion Type
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
Vent Type
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.
Outdoor (No Venting)
Storage Type
Tankless
Application
Residential
Mount Type
Wall
Installation Location
Outdoor
Includes Pump
No
Gas Conversion Kit
Not Available
Performance
Maximum Input Capacity
Maximum Input Capacity
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.
199000 BTU
Minimum Input Capacity
15000 BTU
Flow Rate at 40F Temperature Rise
Flow Rate at 40F Temperature Rise
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
9.5 GPM
Flow Rate at 50F Temperature Rise
Flow Rate at 50F Temperature Rise
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
7.5 GPM
Flow Rate at 60F Temperature Rise
Flow Rate at 60F Temperature Rise
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
6.3 GPM
Flow Rate at 70F Temperature Rise
Flow Rate at 70F Temperature Rise
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
5.4 GPM
Uniform Energy Factor
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.
0.95
Flow Rate at 77F Temperature Rise
4.9 GPM
Ultra Low NOx Emissions
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
Yes
Low NOx Emissions
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. Low NOx appliances emit less than 40 ng/J (nanogram per Joule) of NOx. Learn More
Yes
Electrical Data
Phase
1
Frequency
60 Hz
Dimensions
Gas Connection Size
3/4 Inch
Cold Water Inlet
3/4 Inch
Hot Water Outlet
3/4 Inch
Product Height
23 5/8 Inches
Product Width
17 3/4 Inches
Product Depth
11 1/4 Inches
Product Weight
59 Pounds
Shipping Weight
59 Pounds
Certifications
CSA Listed
Yes
Energy Star Listed
Yes
AHRI Certified
Yes
ANSI Certified
Yes
UPC Listed
Yes
NSF Certified
NSF Certified
The National Sanitation Foundation has developed public health standards and certification programs to protect the world's food, water, consumer products and environment.
Yes
AHRI Reference Number
5526886
Warranty Information
Parts Warranty
Parts Warranty
A warranty is a safeguard from defects in manufacturing and can vary in length and terms. Some manufacturers require registration for extended warranty benefits, be sure to check out features and the warranty document. To see the manufacturer's warranty statement, click on the Manuals tab. Learn More
5 Years
Heat Exchanger Warranty
15 Years
Reviews
(2)
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A.O. Smith ATO-540H - Residential 199,000 BTU - Natural Gas Tankless Water Heater - Outdoor
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