Suburban 233516 Aluminum Anode Rod | 9" | 3/4" NPT | Hard Water

Protect your Suburban RV water heater tank from corrosion with the Suburban Aluminum Anode Rod (Part 233516) — a 9-inch sacrificial aluminum anode with 3/4" NPT thread that absorbs the electrolytic action that would otherwise eat your tank. Available at The RV Surplus.

⭐ Why Your Water Heater Needs an Anode Rod

Water chemistry attacks metal tanks electrolytically. An anode rod is the sacrificial metal that corrodes INSTEAD of your tank, exactly the same way as the water heater in your house.

• No anode rod → the electrolytic action attacks your tank lining directly, leading to pinhole leaks and tank failure
• Fresh anode rod → the rod corrodes while the tank stays protected
• Spent/missing anode rod → the tank is the next thing to go

Replacing the anode rod is one of the most-skipped RV maintenance items — and tank replacement is dramatically more expensive than a new rod.

⚠️ Aluminum vs Magnesium — Match Your Water

• Aluminum rod (this part): generally recommended for HARD water
• Magnesium rod: generally recommended for SOFT water

If you camp mostly in hard-water areas or your RV has well-water fill, aluminum is the right choice. If you're on soft municipal water or regularly use a water softener, consider a magnesium rod instead.

⭐ Fitment

• 9" length
• 3/4" NPT thread size
• Fits Suburban RV water heaters with the standard 3/4" NPT anode port

⚠️ Dometic/Atwood water heaters do NOT use anode rods — they have aluminum tanks that don't need one. Verify you have a Suburban water heater (steel tank with porcelain lining) before ordering.

⭐ When to Inspect and Replace

• Inspect at least once per season — more often with heavy use
• Replace when substantially eaten away — once more than ~75% of the rod is gone, the tank starts corroding next
• If the rod comes out looking like a thin wire, you waited too long — order now and don't skip the next check
• A rod that lasts only a few months indicates very corrosive water — consider a magnesium swap or installing an inline water softener

⚠️ Installation — With the Tank DRAINED

1. Shut off power — both LP gas and 120V AC to the water heater
2. Let the water heater cool completely — never work on a hot tank
3. Turn off incoming water and open a hot faucet to release pressure
4. Drain the tank fully through the drain port / anode location
5. Remove the old anode rod with a 1-1/16" socket
6. Apply fresh thread sealant (Teflon tape or pipe dope rated for potable water) to the new rod's threads
7. Thread the new rod in by hand first to avoid cross-threading, then torque snug — do NOT overtighten
8. Close the drain, open the water supply, bleed air from a hot faucet until flow runs steady
9. Restore power and resume normal operation

⭐ Flush the Tank While the Rod is Out

With the anode removed and tank drained, flush the tank with a water heater tank rinser or a short hose blast through the anode port. Years of sediment settle at the bottom — flushing while you're already in there extends tank life.

What's Included

• (1) Suburban aluminum anode rod, 9" × 3/4" NPT

NOT included: thread sealant / Teflon tape (standard plumbing supply).

Manufacturer Warranty

Backed by Suburban Manufacturing's standard parts warranty. Check documentation for full terms.

Specifications

• Brand: Suburban Manufacturing
• Part Number: 233516
• UPC: 755790713189
• Material: Aluminum
• Length: 9"
• Thread Size: 3/4" NPT
• Application: Hard water (soft water takes magnesium instead)
• Fits: Suburban RV water heaters with 3/4" NPT anode port
• Not For: Dometic/Atwood aluminum-tank water heaters (no anode rod required)