For a home with a substantial hot-water demand, the American G62-100T77-4NOV 400 combines a 98-gallon nominal tank with 75,100 BTU/h natural-gas input. This ProLine high-capacity atmospheric-vent model is listed without side loops and has a six-year limited tank and parts warranty. Its size and input make the existing vent and gas supply central to the replacement decision.
When a 98-gallon tank is worth considering
This model is worth comparing when stored hot water matters—for example, a larger tub draw or several fixtures used close together. We start with how the home uses hot water during its busiest period. A larger tank may address a storage shortage, but it will not by itself correct an undersized supply line, an unsuitable vent or a poorly arranged recirculation system.
American lists 95 gallons of rated storage and a 170-gallon first-hour rating for this exact model. The first-hour number includes recovery during a test; it is not 170 gallons sitting in the tank. We use it as a comparison point alongside fixture flow, incoming water temperature and the timing of demand. A large tank still has a finite supply.
G62-100T77-4NOV 400 specifications
| Exact model | G62-100T77-4NOV 400 |
|---|---|
| Fuel | Natural Gas |
| Nominal capacity / rated storage | 98 gallons / 95 gallons |
| Input | 75,100 BTU/h |
| First-hour rating | 170 gallons, as listed on the exact product page |
| UEF | 0.58 |
| Thermal efficiency | 80%; a separate measure from UEF |
| Side loop | No |
| Product-page dimensions | 65 inches high × 27¾ inches diameter |
| Catalog drawing references | A: 68½ inches; B: 66½ inches; see height discussion below |
| Water connection size | 1¼ inches |
| Insulation blanket supplied | No |
| Limited warranty | 6-year tank and 6-year parts; conditions apply |
No-side-loop configuration
This guide covers the model listed with Side Loop: No. American’s general family description mentions side taps, but the exact product specifications and the catalog’s 98-gallon drawing data are the relevant references for this configuration. A relief-valve connection on the side of the tank should not be confused with a pair of recirculation taps.
If the existing installation uses dedicated side-loop connections, we need to review that piping arrangement before choosing this model. Compare the 74-gallon G62-75T75-4NOV 400 natural-gas model and G62-75T75-4PV 401 propane model. Both are listed with side loops; account for that connection difference as well as capacity when comparing them with this 98-gallon model.
Gas supply, venting and physical fit
The 75,100 BTU/h input is substantially higher than the 40,000 BTU/h rating of the G61-50T40R 400. We review the natural-gas supply with the other connected appliances in mind. Reusing the existing branch simply because the old water heater ran on natural gas can overlook the increased demand.
This is an indoor atmospheric-vent heater. American states that its control system requires no external electrical connection. The absence of a blower does not make venting an afterthought: we assess combustion air, the existing vent route and its condition, including any shared vent arrangement. The installation must follow the instructions applicable to the delivered unit.
At 27¾ inches in diameter, this tank also needs a realistic route into the installation area. We check door openings, working room and space for the drain and water connections. Access for later maintenance belongs in that assessment, especially when a larger tank would occupy most of a closet or utility area.
Height and document checks before ordering
The product page’s 65-inch height is not a complete installed-height allowance. The August 2026 American catalog, printed page 34, shows A = 68½ inches to the draft-hood reference and B = 66½ inches at the upper water-connection reference. Allow additional room for the vent connector, piping and service, and verify the actual supplied assembly for a tight replacement.
The product page lists a 5-inch flue-diameter field, while the catalog lists a 4-inch draft hood. These are separately labeled figures; neither should be used alone to design or approve the vent system. The installer must reconcile the supplied hood and the applicable instructions with the complete vent layout.
The product page’s spec-sheet link currently opens NRGSS00115, whose model table does not include these 74- and 98-gallon heaters. The official catalog linked below contains the correct high-capacity model table. American also links manual 100263114, a general residential FVIR gas manual; confirm the manual supplied for the exact model before relying on its connection or venting details. This guide does not infer FVIR construction from that download link.
Compare capacity and fuel options
The G62-100T77-4PV 401 propane model is the separate fuel counterpart. For a smaller same-fuel tank, compare the G61-50T40R 400 natural-gas model. Moving up to this 98-gallon model changes both the stored-water reserve and the installation requirements.
Browse the American Water Heaters page and the water heater model catalog for other choices. We can review the existing heater, household demand and site measurements together before recommending the replacement.
Maintenance and warranty
Plan for access to the drain, burner area and anode when laying out the installation. A self-cleaning dip tube is not a reason to skip a maintenance schedule. Discuss care for the home’s water conditions and keep the unit’s model and serial number with its installation records.
The listed six-year warranty covers the tank and parts on a limited basis, subject to the manufacturer’s written terms. It does not mean six years of free installation labor. Review eligibility, exclusions and claim requirements in the certificate; a residential rating should not be assumed to carry the same coverage in every application.
Frequently asked questions
Does this 98-gallon model have side-loop connections?
No. American’s exact product page lists Side Loop: No, and its catalog shows no side-loop dimensions for the 98-gallon model. The family’s general marketing language about side taps does not change that model-specific listing.
Is G62-100T77-4NOV 400 a natural-gas or propane model?
G62-100T77-4NOV 400 is the factory natural gas version. Its listed input is 75,100 BTU/h. Confirm the complete model and fuel on the delivered unit’s data plate; the two fuels are not interchangeable configurations.
Is the tank capacity 98 gallons or 100 gallons?
The model name contains 100, but American lists 98 gallons of nominal capacity and 95 gallons of rated storage. The published 170-gallon first-hour rating includes reheating during the test and is not the amount held in the tank.
How much height does the installation need?
The product page lists 65 inches, while the catalog drawing gives A = 68½ inches to the draft-hood reference and B = 66½ inches at the top water-connection reference. Additional vent, piping and service space is needed. Confirm the supplied assembly before deciding whether it fits.
Does the six-year warranty include replacement labor?
American lists six-year limited tank and parts coverage. The written warranty generally excludes removal and installation labor and related expenses. Coverage depends on its eligibility and installation conditions; retain the purchase and installation records.
Official American product documents
- G62-100T77-4NOV 400 product specifications
- American catalog, August 2026 — high-capacity specifications on printed page 34
- Manufacturer-linked manual 100263114 — confirm applicability as noted above
- American residential limited warranty 100287889
Specifications checked October 17, 2026. The photograph is American’s representative high-capacity series image; use the exact model data and supplied instructions to verify the installation.