Suburban\'s magnesium anode rod is the most important maintenance item — the difference between an 8-year tank and a 4-year tank.
Anode types
- Magnesium — standard, most protective. Sulfur smell possible in well water
- Aluminum-zinc — slightly less protective but eliminates sulfur smell
- Both fit Suburban — ¾" NPT × 9-9/16" length
When to replace
- Inspect annually at winterization
- Replace when >50% consumed (you can see the core wire)
- Replace immediately if completely gone (core only)
Procedure
- Turn off heat; close water supply; open hot tap to relieve pressure
- Wait for tank to cool (1-2 hours)
- Catch water with bucket beneath the access door
- Unscrew anode rod with 1-1/16" socket
- Tank drains as anode rod comes out
- Inspect old rod
- Apply Teflon tape to new anode threads (3-4 wraps)
- Install new anode, hand-tight plus ¼-turn
- Close hot tap; refill tank; restore power
Cost
- Magnesium anode rod: $15-25
- Aluminum-zinc anode rod: $20-30
- 10-pack for frequent campers: $80-150
Bottom line
Cheapest most-important Suburban maintenance. Inspect annually; replace at 50% consumed. Aluminum-zinc if sulfur smell at well-water campsites.