Bradford White ships magnesium anode rods on most residential tanks (Defender, ICON, RG-series, M-I electric). Magnesium provides aggressive galvanic protection but depletes faster than AO Smith's Coregard aluminum-zinc — typical replacement cycle is 4-6 years vs 6-8 on aluminum-zinc.
When to replace
- Soft water: 5-6 years
- Average hardness: 4-5 years
- Hard water (well): 2-3 years
- Softened water: 2-3 years (softened water is more aggressive)
Bradford White inspection cycle is 3 years — pull and check at year 3.
Aluminum-zinc upgrade
Bradford White offers an aluminum-zinc anode upgrade through dealers. The upgrade trades aggressive protection for longer service life (6-8 years between replacements vs 4-6 on magnesium). For most water conditions, the aluminum-zinc upgrade is the better long-term play.
How to replace
- Shut off power (electric) or gas
- Shut off cold inlet, open hot faucet to break vacuum
- Drain 3-5 gallons
- Locate anode access at top center of tank
- Apply penetrating oil around hex base, soak 15 min
- Break anode free with 1-1/16" socket on 24"+ breaker bar
- Install new anode with Teflon tape, torque ~80-100 ft-lbs
- Refill tank, restore power/gas
Sulfur smell from hot water?
Magnesium anodes can react with sulfate-reducing bacteria to produce sulfur smell ("rotten egg" odor) in hot water. Switching to aluminum-zinc eliminates this. If your Bradford White produces sulfur smell, upgrading the anode is the fix.
Bottom line
Replace at year 4-5 (or year 3 in hard water). Consider the aluminum-zinc upgrade for longer service intervals. For full parts directory see parts hub.