Fit a Cylinder Anode

Normally the rust will sit quietly in a cylinder or part of a plumbing system and remain undiscovered until, say, the cylinder develops a leak. By this point though the damage has already been done and there is a very real risk that you will have a flood situation on your hands. There is, however, a piece of metal shaped like a rod that is called an anode. This is designed to be fitted in the top of a cylinder. The anode is there to help reduce the rusting of the cylinder walls. It is sometimes referred to as a ‘Sacrificial Anode’. The names comes from the action that it performs, in other words it sacrifices itself instead of the tank metal. This anode is made from magnesium and zinc and will start to rot before the cylinder metal, increasing the life of the cylinder.


Anode Condition:
You can’t see the condition of an anode. You will need to undo and remove from the cylinder. This will require the heater power isolated and the anode removed so it can be visually inspected. Barnet Plumbers are experienced with this piece of kit. This operation needs to be carried out every two years, because the rusting is a slow process. The anode is easy to remove and replace. There are many different types available so it will help to have the relevant information for your system to hand when you need to purchase a new one. This detail is usually on the water-heater body itself.

Method of Replacement:
1). Isolate the electrical power to the immersion heater. Isolate the cold water feed to the cylinder. This is done at the inlet valve.
2). Unscrew the hexagonal securing nut holding the anode in place on the top of the cylinder.
3). Take the anode out of the cylinder and dispose of it responsibly.
4). Sit the new anode in its place in the cylinder. A Barnet Plumber can replace this. Turn the power back on and turn the inlet valve on.


Note: Teflon tape can be used on the threads of the nut to prevent it leaking. Return the power supply and visually inspect your work.