By The Energy People

08/28/2025 Inside every storage water heater is a small but essential component most homeowners never think about: the sacrificial anode rod. It isn’t high-tech or expensive, yet without it, your tank would corrode far sooner than expected. When it stops working, the result can be significant damage, costly repairs, or even a complete system replacement. Knowing what this part does and how to maintain it can greatly extend the life of your water heater.

How the Anode Rod WorksThe anode rod is a metal shaft, usually made from magnesium, aluminium, or an alloy containing zinc, inserted into the tank’s interior.
Its sole purpose is to protect the steel walls from rust by drawing in corrosive minerals through a process called galvanic corrosion.
Over time, these elements consume the rod instead of the tank, hence the name “sacrificial” anode.
As long as the rod remains intact, your system is shielded.
However, after a few years, it naturally degrades, leaving your tank vulnerable to corrosion and eventual leaks.
Signs of a Failing Anode RodWhen the rod is nearly depleted, the steel tank starts to corrode directly.
This often begins with small rust patches that gradually weaken the tank until it leaks or fails completely.
Common early indicators include:

• Brown or rusty water from your taps
• A metallic taste or smell in the water
• Popping or rumbling noises while heating
• Sediment buildup at the bottom of the tank

Homes with hard water or older units are particularly at risk.
For example, if you have a gas hot water system in Canberra, the rod may wear out faster without regular servicing.

Checking and Replacing the RodA quick inspection every 2–3 years can prevent costly tank replacements.
The rod is generally accessible beneath a hexagonal fitting at the top of the heater.
If it’s coated in mineral deposits, heavily pitted, or reduced to less than half its original thickness, it’s time for a new one.
While some homeowners handle this themselves, it involves draining the tank and using specific tools.
If you’d rather not take the DIY route, a technician experienced with hot water systems in Canberra servicing can manage it safely.

Why Maintenance Pays Off
A well-maintained anode rod can add years to your heater’s lifespan.
Without one, even a newer model can deteriorate rapidly, especially during heavy winter use when Canberra hot water demand peaks.
Regular checks and timely replacements help ensure reliable performance and protect your investment in the long run