Understand the FCG-75 model
A.O. Smith markets the FCG-75 400 as a 75-gallon model. Its manufacturer specifications list a nominal capacity of 74 gallons and a rated storage volume of 71 gallons. These are different capacity labels for the same model, rather than different tank options.
This guide concerns the natural gas, atmospheric-vent version. A.O. Smith also makes other large gas tanks with different venting arrangements. The FCG-75 is not the same model as a GPVX power-vent heater, and similar capacity does not make them interchangeable.
Plan a replacement around your home
We review the existing model, gas supply, venting and combustion-air requirements, along with available space, clearances and access. Even when replacing a tank in the same capacity class, changes to the installation may be necessary.
Tell us whether your current heater keeps up with showers and appliances used together. Photos of its readable model label, visible connections and surrounding space help us assess the project and discuss suitable alternatives.
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A.O. Smith FCG-75 questions
Why does a 75-gallon model list 74 gallons?
A.O. Smith uses 75 gallons in the product name and lists 74 gallons as nominal capacity and 71 gallons as rated storage volume for the FCG-75 400. We consider household demand and installation requirements alongside capacity.
Can an FCG-75 replace a power-vent heater?
It is not an automatic substitute. The FCG-75 uses atmospheric venting. WHE needs to review the existing vent system, location and other installation requirements before recommending equipment.
How do I request an FCG-75 installation estimate?
Choose the free installation estimate option and mention A.O. Smith FCG-75 when we follow up. For questions about an existing heater, call 561-602-9062.
Model reference: A.O. Smith’s official FCG-75 400 specifications.