EcoSmart ECO 36 36kW Electric Tankless Water Heater

The EcoSmart ECO 36 is the largest unit in EcoSmart's whole-house electric tankless line at 36 kW. It is the answer for 3+ bathroom homes in cold-climate regions without natural gas service — a scenario that's hard to serve with anything smaller in electric tankless. Three 50-amp double-pole breakers, 150A continuous draw at 240V. Requires substantial 200A service headroom; some homes need an electrical-service upgrade just to accommodate this unit.

Capacity at the tap: about 3.6 GPM at a 60°F rise (typical Northeast winter) or 5.5 GPM at a 40°F rise (Sun Belt). Two simultaneous showers possible in any US climate, plus a kitchen tap. Stainless steel heat exchanger tolerates hard water well; lifetime warranty on both heat exchanger and electronics.

The right buyer is a multi-bathroom household with 200A+ electrical service, no gas option, and a willingness to accept the highest install cost in the electric tankless category. About $920 unit, $2,400 installed including the electrical work. Wrong buyer: homes with 100A or 150A service (will trip breakers under load), single-bathroom homes (massively oversized), or anyone where a heat-pump tank could fit the install location (cheaper to run by far).