Rheem Performance 75-Gallon Atmospheric Gas Water Heater

The Rheem Performance 75-Gallon Atmospheric Gas Water Heater (XG75T06ST76U0) is the high-capacity atmospheric gas tank — 75-gallon volume for 5–7 person households or homes running 3+ simultaneous demand points. 76,000 BTU recovery, 6-year warranty, atmospheric venting. The volume-channel sibling of the higher-warranty Performance Platinum 75G.

Headline specifications

• Model: XG75T06ST76U0
• Capacity: 75 gallons
• Fuel: Natural gas, atmospheric vent
• BTU input: 76,000 BTU/h
• First Hour Delivery: 120 GPH
• Recovery: 76 GPH at 90°F rise
• UEF: 0.60
• Warranty: 6-year
• Dimensions: 70" H × 24" diameter

Who this model is for

5–7 person households with 3+ bathrooms running concurrent showers, homes with whirlpool tub or hot-tub fill demand, light-commercial residential (in-home daycares, small B&Bs, group homes), homes upgrading from a 50G tank that's consistently running short. Existing natural gas service with chimney/atmospheric flue access required.

For 3–4 person households, the Performance Plus 50G at lower upfront cost is sized better. For 5+ person households wanting longer warranty, step up to the Performance Platinum 75G with 12-year warranty + EcoNet WiFi. For long-term high-demand efficiency, the Rheem RTGH-95DVLN tankless at 9.5 GPM handles equivalent simultaneous demand with much higher operating efficiency.

Where it beats the alternatives

Vs Performance Platinum 75G ($1,649): Performance 75G is ~$300 less. Trade is 6-year vs 12-year warranty and no EcoNet WiFi. For shorter-horizon ownership, Performance wins; for longest-warranty math, Platinum.

Vs dual Performance Platinum 40G cascade: single 75G is simpler — one vent, one gas drop, one maintenance schedule. Dual 40G cascade adds redundancy at higher install cost. Single 75G usually correct.

Vs AO Smith ProLine Master 75G ($1,549 plumber channel): AO Smith 10-year warranty + Coregard anode + power vent option. Rheem 6-year + atmospheric. AO Smith wins on warranty and feature set; Rheem wins on big-box availability.

Where it falls short

0.60 UEF is class-baseline atmospheric. Operating cost for a 75G tank running 5–7 person household demand: $450–$650/year. A condensing tankless (e.g. Rheem RTGH-95DVLN) handling the same demand: $300–$420/year. Over 10 years the operating-cost delta is $1,500–$2,300.

70" height + 24" diameter is large. Won't fit standard utility closets. Requires basement, garage, or large mechanical room.

76,000 BTU is high recovery for a tank but requires proper gas-line sizing — verify 1/2" or 3/4" capacity at install.

Atmospheric venting requires chimney access. No 75G power-vent or condensing variant at this Performance tier — for those, see Performance Platinum 75G or step into tankless territory.

6-year warranty is short for a $1,300 unit. Plumber-channel competitors offer 10-year at similar price.

Install considerations

70" height + 24" diameter — verify clearance and door-frame access. Atmospheric flue must be sized for 76,000 BTU input — verify B-vent diameter. 1/2" gas line at typical residential runs (3/4" preferred for long runs).

Install cost: $1,200–$2,100 like-for-like swap with existing 75G atmospheric.

Maintenance

• Annual flush — 75G accumulates more sediment than 50G
• Anode check year 3, replace year 5
• T&P valve test annually
• Burner inspection every 2 years (76K BTU burner has more parts than 40K)

Bottom line

The Rheem Performance 75G Atmospheric Gas (XG75T06ST76U0) is the volume high-capacity Rheem gas tank — 120 GPH FHD, 76K BTU recovery, 6-year warranty. Right pick for 5–7 person households needing tank simplicity at the highest-residential capacity tier. For longest warranty + WiFi, step up to Performance Platinum 75G. For lifetime operating-cost minimization, condensing tankless wins.