Rheem Performance 40-Gallon Electric Water Heater

The Rheem Performance 40-Gallon Electric Water Heater (XE40M06ST45U1) is Rheem's volume-shipping budget-tier electric tank — the unit that replaces failed electric tanks in millions of US homes every year. 53 GPH first-hour delivery. Dual 4,500W elements. 0.93 UEF. 6-year warranty. About $449–$549 retail. The right pick for straightforward like-for-like electric retrofit in 1–3 person households where a heat pump isn't viable.

Headline specifications

• Capacity: 40 gallons
• Fuel: Electric
• Heating elements: Dual 4,500W (upper and lower)
• Voltage: 240V single phase
• First Hour Delivery: 53 GPH
• Recovery: 21 GPH at 90°F rise
• Energy Factor (UEF): 0.93
• Warranty: 6-year tank and parts
• Dimensions: 47.5" H × 20" diameter (shorter form factor than gas tanks)

Who this model is for

The Performance 40G Electric is calibrated for 1–3 person households in homes without natural gas service, or homes where the existing water heater is electric and the install cost of converting to gas isn't justified. It's also the right pick for installs where heat-pump alternatives don't fit — closets, conditioned-space installs, or homes without 700 cu ft ambient air for a hybrid heat pump.

Owners stay in this category for the upfront price and install simplicity: no gas line, no venting, no combustion air requirement, no condensate drain. Just hardline it into a 240V circuit and connect water lines.

Where it beats the alternatives

Vs AO Smith Signature 100 40G Electric ($429): AO Smith ships at slightly lower price. Spec equivalent. Choice usually comes down to retailer (Rheem at Home Depot, AO Smith at Lowe's).

Vs Whirlpool 40G Electric ($399): Whirlpool is AO Smith manufacturing at $50 less. 6-year warranty matches. Pure price-shopping pick.

Vs Rheem Performance Platinum 40G Gas ($949): if you have gas service, the gas tank has lower operating cost in most US regions ($230 vs $440 annual for typical 3-person demand) but $400+ higher upfront. Electric wins on upfront simplicity; gas wins on operating cost.

Vs Rheem ProTerra Hybrid 50G Heat Pump ($1,799): ProTerra costs $1,300 more upfront but cuts operating cost by 70%. With IRA tax credit ($540) + state/utility rebates, net upfront premium often drops to $200–$500. ProTerra wins on lifecycle math if install space is available.

Where it falls short

0.93 UEF is competitive for resistance electric but well below heat-pump (3.4+ UEF). Operating cost runs $380–$460/year for typical 3-person demand — about 60% higher than gas, 3.5× higher than heat pump.

21 GPH recovery rate is slower than gas. Households running back-to-back simultaneous showers will hit a wait period as the tank recovers. For high-demand patterns, step up to 50G or move to a heat pump.

6-year warranty is shorter than premium-tier alternatives (Performance Platinum gas at 12 years, ProTerra HP at 10).

Install considerations

Dedicated 30-amp 240V circuit (10 AWG copper). Standard 1" cold/hot connections. No venting, no gas line, no combustion air. 47.5" height fits most basement, closet, and utility-room installs.

Install cost: $200–$500 like-for-like swap (no gas/venting work, simpler scope).

Maintenance

• Annual flush
• Anode rod inspection year 3, replace year 5
• Element inspection year 8–10 (failed elements are the typical end-of-life event for electric tanks)

Bottom line

The Rheem Performance 40-Gallon Electric is the straightforward budget pick for 1–3 person households needing a straightforward electric tank replacement. Lowest install scope of any water heater category. For buyers with heat-pump install space, the ProTerra Hybrid wins on lifecycle math; for buyers without that space, this is the default. Click through to Amazon or Home Depot for live pricing.