Reliance 6 66 EORS 66-Gallon Electric Water Heater
Reliance 6 66 EORS 66-Gallon Electric Water Heater Review
The Reliance 6 66 EORS is a 66-gallon electric water heater built by A.O. Smith and sold under the Reliance brand. The "6 66 EORS" naming reflects 6-year warranty, 66-gallon capacity, electric residential.
Specs: 66 gallons stored, two 4500W heating elements (240V), UEF 0.93, 80-gallon FHR, 6-year tank and 1-year parts warranty. Glass-lined steel tank, magnesium anode rod.
The 66-gallon capacity covers 4-5 person households on a budget. Bridges the gap between standard 50-gallon and larger 80-gallon electric tanks.
About $649 unit, $1,250 installed. For households with basement install supporting heat-pump, the upgrade to Reliance 66-gal Hybrid Heat Pump or AO Smith Voltex Premium HPTU-66 operating cost (75% lower) usually makes that the better economic choice.
Right buyer: 4-5 person primary residence with electric utility only, 5-7 year ownership horizon, install location not supporting heat-pump.
- No combustion, no venting required — installs anywhere with 240V electrical access
- Strong UEF 0.93 efficiency — approximately 20% lower annual operating cost vs 0.62 standard
- 66-gallon capacity — right-sized for 3–4 person households with standard usage patterns
- 6-year warranty — below the 8–12 year average for premium models in this class
- Resistance electric has slower recovery than gas at comparable capacity — schedule heavy use to match tank recovery