AO Smith Signature 100 80-Gallon Electric Water Heater

The AO Smith Signature 100 80-Gallon Electric Water Heater (EJC-80) is the high-capacity Lowe's-channel electric pick for 4+ person households or homes with multiple simultaneous demand points. 89 GPH first-hour delivery, 0.90 UEF, 6-year warranty. The 80-gallon resistance electric exists because not every house can support a heat pump and not every owner wants tankless complexity.

Headline specifications

• Capacity: 80 gallons
• Fuel: Electric, 240V
• Element: 4500W upper + 4500W lower
• First Hour Delivery: 89 GPH
• Recovery: 21 GPH at 90°F rise
• UEF: 0.90
• Warranty: 6-year tank and parts
• Anode: magnesium
• Dimensions: 60" H × 26" diameter

Who this model is for

The 80-gallon electric is the right pick for: 4–6 person households on all-electric service, homes with 3+ bathrooms running concurrent showers, properties where heat-pump install is blocked (insufficient air volume, cold basement, no condensate drain), and short-term owners who want resistance simplicity over hybrid complexity.

For long-horizon owners with a basement clearing 1,000+ cu ft, the Voltex 80 HP uses one-third the electricity. For households below 4 people, drop to 50-gallon.

Where it beats the alternatives

Vs Voltex 80 HP ($2,049): the Voltex is 3x more efficient but adds $600+ and needs ambient air, condensate drain, and 8 ft headroom. Signature 100 80 fits anywhere 240V power runs.

Vs Rheem Performance 80 Electric ($999): spec-equivalent (both ~6-year warranty, ~0.90 UEF). AO Smith ~$50 less at Lowe's. Tie-breaker by retailer preference.

Vs Bradford White 80 Electric ($1,149): Bradford White ships through plumber channel — better tank longevity historically, but no big-box availability and ~$200 more. Choose AO Smith for DIY install or budget constraint.

Where it falls short

80-gallon resistance electric is expensive to run. Operating cost runs $700–$1,000/year for 4–6 person households. A Voltex Hybrid at the same capacity runs $250–$350/year. The 5-year operating cost delta is $2,000–$3,000 — exceeds the upfront premium of the heat pump by a wide margin.

60" height + 26" diameter limits closet install. Requires utility-room or basement space.

30-amp dedicated 240V circuit needed. Older homes with 100-amp service may struggle to support 80-gallon resistance electric plus typical loads.

Install considerations

26" diameter is wider than 20" standard 50G — measure clearance carefully. 30-amp 240V dedicated circuit required; some installs need service upgrade.

Install cost: $500–$900 for like-for-like swap with existing 80G electric. Conversion from smaller tank or gas: $900–$1,800.

Maintenance

• Annual flush (80G holds more sediment than 50G — flush is more important)
• Anode check year 3, replace year 5
• T&P valve test annually
• Two-element inspection every 3 years

Bottom line

The AO Smith Signature 100 80 Electric is the high-capacity resistance pick for 4+ person all-electric households that can't or won't install a heat pump. 89 GPH FHD, 0.90 UEF, 6-year warranty. For households long-horizon enough to amortize the upfront delta, the Voltex 80 HP saves $400–$600/year in electricity.