- ENERGY STAR® certified
- Continuous flow rate up to 10.0 GPM
- Integrated recirculation pump
- Primary commercial-grade copper heat exchanger is 25x better than stainless steel at heat transfer, stabilizing outgoing water temperatures quicker
- Secondary heat exchanger is made of 316L Stainless Steel to protect against corrosion
- Highly efficient condensing Ultra-Low Nox tankless water heater delivers up to .95 Uniform Energy Factor (UEF)
- Common vent up to 8 units, Easy-Link 540P with three other 540H to increase flow capacity
- Includes a wall mount temperature remote controller and advanced diagnostics to simplify troubleshooting
- Safety features include exhaust & water temperature safety control, overheat cut-off fuse and air-fuel ratio (AFR) sensor
- 15-year limited warranty on heat exchanger in residential applications
The 540P series integrates a recirculation pump to provide instant hot water in residential applications with dedicated recirculation lines. The pump is easily controlled with a simple user interface and multiple pump settings allow you to customize pump operation to meet your needs while maximizing heater efficiency. As part of the high efficiency tankless family, the 540P series provides endless hot water while being environmentally friendly. The ATO-540P-N outdoor tankless water heater uses up to 199,000 BTU/hr of natural gas to deliver an endless supply of hot water for a 3 bath home in northern climates and a 4 bath home in southern climates. It is built with commercial grade materials like marine-grade 316L stainless steel giving it an industry-leading warranty. A. O. Smith’s ProLine® water heaters are residential products built to commercial-grade standards and are only available for purchase through professional wholesalers and contractors.