Rheem Performance 30-Gallon Short Electric Water Heater

The Rheem Performance 30-Gallon Short Electric Water Heater (XE30S06ST45U1) is the tight-clearance electric tank — 30-gallon capacity in a 38"-tall lowboy form factor. The right pick for 1–2 person households with severe clearance constraints: crawl spaces, manufactured-home utility cabinets, RV/cabin installs, attic-mount applications.

Headline specifications

• Model: XE30S06ST45U1
• Capacity: 30 gallons
• Fuel: Electric, 240V
• Element: 4500W upper + 4500W lower
• First Hour Delivery: 42 GPH
• Recovery: 21 GPH at 90°F rise
• UEF: 0.93
• Warranty: 6-year
• Dimensions: 38" H × 22" diameter (lowboy)

Who this model is for

1–2 person households, ADUs / mother-in-law suites / garage apartments serving 1–2 occupants, manufactured homes with tight utility cabinets, RVs and cabins with minimal headroom, attic-mounted installs in 1930s–1950s homes where roof framing limits height. The 38" lowboy form factor is the lowest residential gas/electric tank Rheem makes — fits under standard 42" countertops.

For 2–3 person households, the Performance 38G Short Electric adds 8 gallons of capacity in a 43" form factor. For under-sink point-of-use, the Performance 6G Mini-Tank at 14" cube is the alternative single-fixture pick.

Where it beats the alternatives

Vs full-height 30G electric (e.g. AO Smith Conservationist 30G): Rheem 30G Short fits in 38" clearance vs ~47" standard. Same capacity, same warranty class. Choose short only when clearance demands it.

Vs Performance 20G Point-of-Use: 30G Short adds 10 gallons of capacity for ~$80 more. If your usage exceeds 20-gallon-per-evening pattern, step up to 30G.

Vs running plumbing from main water heater: for ADUs or detached structures, point-of-use 30G eliminates trenched hot-water plumbing — saves $1,500–$3,500 in plumbing labor.

Where it falls short

42 GPH FHD is the limit — single bathroom only. Two-shower demand will exhaust the tank.

21 GPH recovery is slow. Full reheat after depletion ~90 minutes.

0.93 UEF resistance electric. Operating cost $300–$400/year for 1–2 person households at $0.14/kWh.

6-year warranty class-baseline.

Lowboy geometry accumulates sediment — flush is more important than tall-tank installs.

Install considerations

38" height + 22" diameter. Verify floor-to-ceiling clearance accounts for ~6" above for connections. 30-amp 240V dedicated circuit. Drain pan recommended.

Install cost: $350–$750 like-for-like swap.

Maintenance

• Annual flush — critical for lowboy
• Anode check year 3, replace year 5
• T&P valve test annually
• Element inspection year 5

Bottom line

The Rheem Performance 30G Short Electric (XE30S06ST45U1) is the lowboy electric pick — 38" tall lowboy form factor for crawl space, manufactured home, and attic installs. 42 GPH FHD, 6-year warranty. For more capacity in moderately less clearance, see Performance 38G Short Electric. For full-clearance 30G installs, the standard Performance 30G Electric saves ~$50.