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EcoSmart ECO 36 36kW Electric Tankless Water Heater

Model ECO 36
4.3/5 from 820 ratings
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Wattage
36000
Fuel Type
Electric
Tank Type
Tankless
Energy Factor
0.99
Flow Rate Gpm
8.4
Warranty Years
5

EcoSmart ECO 36 36kW Electric Tankless Water Heater Review

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).

Pros
  • Tankless electric — zero standby loss; no pilot, no venting, minimal footprint
  • UEF 0.99 — top-tier efficiency; qualifies for Inflation Reduction Act §25C residential credit
  • 8.4 GPM flow rate — sized for 2-bath simultaneous demand in warm-climate installs
Cons
  • 5-year warranty — below the 8–12 year average for premium models in this class
  • Requires 36 kW dedicated circuit — may need 200–300A electrical service upgrade at additional cost

Full Specifications

Brand
EcoSmart
Model Number
ECO 36
Wattage
36000
Fuel Type
Electric
Tank Type
Tankless
Energy Factor
0.99
Flow Rate Gpm
8.4
Warranty Years
5

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