The 540 series is suited for residential use and heavier-residential usages such as domestic recirculation systems. The series utilizes commercial grade copper alloy for the heat exchanger tubing. The product includes a remote control on all Outdoor models. Indoor models are certified up to 10,100 ft. altitude. The product provides a variety of installation options: outdoor and direct vent. It complies with Ultra-Low NOx regulations and meets the energy efficiency requirements.
The ATI-540H-N tankless water heater uses up to 199,000 BTU/hr of natural gas to deliver an endless supply of hot water for a three bath home in northern climates and up to a four bath home in southern climates (one shower head per bath). Utilizing condensing technology, this heater is efficient with a Uniform Energy Factor of 0.93.