American Water Heater water heater parts are sourced from the A.O. Smith (parent company) part catalog. Common residential wear items are universal aftermarket — only brand-specific parts (gas valves with proprietary controls, specific anode kits) require OEM ordering.
Common replacement parts
Heating elements (electric models)
Standard 1" NPT screw-in elements at 4500 W 240V. Universal aftermarket fits: Camco 02922, Reliance 100109109 — $15–25. OEM: $35–55.
Thermostats
Dual-stage upper (with reset/high-limit) and lower (single-stage). Compatible aftermarket: Therm-O-Disc 59T, Honeywell L4080 — $25–40 each.
Gas valves (gas models)
Modern American Water Heater gas units use Honeywell or Robertshaw gas valves with integrated ignition control. Verify model number before ordering — $180–280 OEM. Gas-fitter expertise required for replacement.
Anode rod
3/4" NPT, 42–46" long. Universal: $25–65 depending on type (rigid magnesium, flexible for tight-ceiling installs, or aluminum-zinc for sulfur-water areas).
T&P relief valve
Standard ASME-rated 3/4" NPT, 150 psi / 210°F. Any compatible: Watts 100XL, Honeywell EW100, Apollo — $15–30.
Dip tube
Universal residential dip tube fits American Water Heater tanks — $8–15.
Drain valve
Standard 3/4" NPT brass boiler drain — $12–25.
Where to source American Water Heater parts
- A.O. Smith (parent company) parts direct: typically the broadest catalog and OEM-authentic parts
- Home Depot, Lowe's: universal aftermarket parts (elements, thermostats, T&P, anodes)
- Plumbing supply houses (Ferguson, HD Supply): mid-tier parts inventory, faster for contractor accounts
- Amazon: universal aftermarket parts; faster shipping, often cheaper
Locating part numbers
The data plate on every American Water Heater water heater lists the model number, serial number, and manufacture date. Cross-reference the model on A.O. Smith (parent company)'s parts website for an exact match. Universal parts (elements, anodes, T&P) match by spec, not by part number.