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AO Smith Vertex Power Direct Vent 75-Gallon Gas Water Heater

Model GPDX-75
4.5/5 from 180 ratings
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Btu
100000
Fuel Type
Natural Gas
Tank Type
Tank
Energy Factor
0.89
Warranty Years
8
Capacity Gallons
75

AO Smith Vertex Power Direct Vent 75-Gallon Gas Water Heater Review

The AO Smith Vertex Power Direct Vent 75-Gallon Gas is A.O. Smith's premium 75-gallon condensing gas tank with power direct-vent venting. Higher BTU output and longer service life than typical 75-gallon atmospheric tanks.

Specs: 75 gallons stored, 100,000 BTU input, UEF 0.86 condensing, 150-gallon FHR, 8-year tank warranty. Sealed direct-vent PVC venting. ENERGY STAR certified.

The Vertex 75-gal combines large capacity + high BTU + condensing efficiency in one unit. Recovery rate ~95 gph at 90°F rise — substantially faster than typical 75-gallon atmospheric units (~70 gph). The combination handles 5+ person households with overlapping demand without the install complexity of tankless conversion.

About $1,700 unit, $3,400 installed including direct-vent piping. For households considering very-large-capacity solutions, the Vertex 75-gal sits between standard 75-gallon atmospheric ($2,200 installed, slower recovery) and parallel tankless install ($7,500+, endless hot water).

Pros
  • Natural gas combustion — faster recovery than electric resistance at comparable tank size
  • UEF 0.89 — 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
  • 165-gallon first-hour rating — handles morning-rush simultaneous demand without shortfall
  • High 100K BTU input — rapid recovery for large-volume commercial-residential applications
Cons
  • Tank standby heat loss — tankless or heat-pump alternatives eliminate this continuous efficiency gap

Full Specifications

Brand
AO Smith
Model Number
GPDX-75
Btu
100000
Fuel Type
Natural Gas
Tank Type
Tank
Energy Factor
0.89
Warranty Years
8
Capacity Gallons
75
First Hour Delivery
165

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