The Best Tankless Water Heaters

The ATI 540H Tankless Water Heater is well suited for residential/commercial applications such as residential homes, small restaurants, and beauty salons. Utilizing HRS35 copper alloy for the heat exchanger tubing, the 540H is also suitable for heavier-residential usages such as space heating or domestic recirculation systems. Remote control included as a standard feature. Indoor models are certified up to 10,100 ft. altitude. AO Smith uses a thicker heat exchanger drum and utilizes HRS35 (heat-resistant) copper for the heat exchanger tubing which provides more efficient heating and heat retention. Provides a variety of installation options: outdoor and direct vent. Includes a pump control port, ensuring efficient operation of all circulation pumps. Complies with Ultra-Low NOx regulations and meets the energy efficiency requirements of ASHRAE 90.1b-1992. Easy-Link System capable up to 4 units. Multi-Link System capable up to 20 units.

ATI 540H-N

The ATI-540H-N tankless water heater uses up to 199,000 BTUs of natural gas to deliver a max flow rate of 6.6 GPM. It utilizes condensing technology to achieve an Energy Factor of 0.95, and is ENERGY STAR® qualified. This model meets Ultra-Low NOx emission requirements, and comes with a 15-year limited warranty.