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AO Smith Cyclone Xi 75-Gallon Commercial Gas Water Heater (FCG-75)

Model FCG-75
4.3/5 from 160 ratings
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Btu
76000
Venting
Atmospheric
Fuel Type
Natural Gas
Tank Type
Commercial
Energy Factor
0.85
Warranty Years
3

AO Smith Cyclone Xi 75-Gallon Commercial Gas Water Heater (FCG-75) Review

The AO Smith Cyclone Xi 75-Gallon Commercial Gas (FCG-75) is a commercial-grade large-capacity gas water heater. The "FCG-75" identifies the 75-gallon variant in the Cyclone commercial line.

Specs: 75 gallons stored, 199,000 BTU input, UEF 0.97 condensing, 240-gallon FHR, 8-year tank warranty. Power-vent PVC venting. Cyclone heat exchanger uses spiral flow paths for maximum heat transfer.

The Cyclone Xi 75-gallon serves light commercial applications (small restaurants, salons, small multi-family residential) or very-large residential (6+ bath homes with overlapping demand). The UEF 0.97 is among the highest in the gas tank category.

About $4,200 unit, $6,500-$8,500 installed depending on venting work. Right buyer: small commercial application or very-large residential where parallel tankless install would otherwise be required.

Pros
  • Natural gas combustion — faster recovery than electric resistance at comparable tank size
  • UEF 0.85 — above federal minimum EF 0.62; solid efficiency for a non-condensing gas unit
  • 75-gallon capacity — right-sized for 3–4 person households with standard usage patterns
  • 185-gallon first-hour rating — handles morning-rush simultaneous demand without shortfall
Cons
  • 3-year warranty — well below the 8–12 year category average; extended warranty advisable
  • Atmospheric venting requires vertical B-vent — less routing flexibility than power-vent or condensing alternatives

Full Specifications

Brand
AO Smith
Model Number
FCG-75
Btu
76000
Venting
Atmospheric
Fuel Type
Natural Gas
Tank Type
Commercial
Energy Factor
0.85
Warranty Years
3
Capacity Gallons
75
First Hour Delivery
185

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