AO Smith Conservationist 30-Gallon Electric Water Heater

The AO Smith Conservationist 30-Gallon Electric Water Heater (ECT-30) is the compact electric tank for 1–2 person households, ADUs, in-law suites, garage apartments, and small condos. 0.92 UEF, 42 GPH first-hour delivery, 4500W elements, 6-year warranty. The Conservationist line is AO Smith's plumber-channel value-electric tier — built lean, sized small, priced accordingly.

Headline specifications

• Capacity: 30 gallons
• Fuel: Electric, 240V
• Element: 4500W upper + 4500W lower (non-simultaneous)
• First Hour Delivery: 42 GPH
• Recovery: 21 GPH at 90°F rise
• UEF: 0.92
• Warranty: 6-year tank and parts
• Anode: magnesium
• Dimensions: 47" H × 18" diameter

Who this model is for

30-gallon electric is correct for: 1–2 person households with single-bathroom use, ADUs / mother-in-law suites / garage apartments serving 1–2 occupants, studio condos, vacation cabins with intermittent use, single point-of-use applications like a basement bathroom or wet bar where a 50G tank is overkill.

For 2–3 person households step up to 40-gallon. For 3+ people, 50-gallon. The 30G is specifically for small-household / small-footprint applications where the smaller tank's lower upfront cost and tighter form factor matter.

Where it beats the alternatives

Vs Rheem Performance 30 Electric ($429): nearly identical price and warranty (6 years). Choose AO Smith if your installer/retailer is AO Smith-channel.

Vs Signature 100 40 Electric ($549): 30G saves $100 upfront. Adequate for 1–2 person households. If you're on the bubble (2-3 people), step up to 40G — the $100 buys an extra shower per evening.

Vs EcoSmart ECO 18 tankless electric ($549): tankless electric needs heavy 240V service (~75 amps). For a 1–2 person ADU, the 30G tank is much simpler and uses standard 30-amp circuit.

Vs point-of-use mini-tanks (2.5–10G): point-of-use is for single sinks only. The 30G handles full bathroom + kitchen for 1–2 occupants.

Where it falls short

42 GPH FHD is the limit. Two showers within an hour will run cold. Plan around the recovery curve.

0.92 UEF is class-standard for resistance electric. Heat-pump units at this capacity don't exist (heat pumps start at 50G). For small-household efficiency, EcoSmart tankless electric is the only alternative — at the cost of electrical service complexity.

6-year warranty is class-baseline. Rheem doesn't offer a 12-year Platinum equivalent at 30G — the 30G tier is universally 6-year.

Install considerations

47" height + 18" diameter fits very tight closet and pantry installs. Standard 30-amp 240V dedicated circuit. Drain pan recommended.

Install cost: $250–$550 like-for-like swap. ADU new install: $400–$800 depending on circuit run.

Maintenance

• Annual flush
• Anode check year 3, replace year 5
• T&P valve test annually
• Element inspection at year 5

Bottom line

The AO Smith Conservationist 30G Electric is the small-footprint electric pick for 1–2 person households, ADUs, and compact applications. 42 GPH FHD, 6-year warranty, fits 18" diameter closets. For 2–3 person households step up to 40-gallon. For point-of-use single-sink applications, drop to a 2.5–10G mini-tank. Click through for live AO Smith distributor pricing.