The steel used to make water heater tanks is protected from corrosion by anodes. The anode sacrifices itself (corrodes) so that the tank can last longer. Thus, the anode has to be replaced periodically so that the tank can last for a long time. Anodes are of two major types, rigid anodes and flexible anodes. The rigid ones are made from a single metal rod section while the flexible ones have several jointed sections (such as a string of sausages). This article discusses some of the weaknesses of rigid anodes that are addressed by flexible water heater anodes.
Confined Space Installation Challenges
It is very hard to install a rigid water heater anode if your water heater is located in a place with limited headroom. This is because you will be unable to raise the anode above the heater so that it can be installed into the tank. You may be compelled to bend it. This can damage its surface and reduce its effectiveness. Flexible anodes solve this dilemma. The sections of this anode can be slipped into the tank independently without having to bend the anode.
Risks of Making Contact with the Tank
Rigid anodes can shift and touch the surface of the wall of the water heater tank. This can damage the glass coating inside the tank and expose the steel underneath to agents of corrosion. The rigid anode can alter its orientation if the installer did not secure it firmly. Flexible anodes do not pose this risk. The joints allow the sections to maintain the straight orientation due to the force of gravity acting upon them. Thus, the anode will not accidentally damage the tank wall even if it was loosely installed.
Owners of hot water heaters that have rigid anodes have to remove the anode completely in order to check how much the anode has worn out. This is not only inconveniencing but also potentially risky. For instance, there is a risk that the tank will be exposed to corrosion during the time when the anode is removed. This risk can be managed by draining the tank before you remove the anode (another inconvenient and time-consuming task). You only need to remove a flexible anode partially in order to establish the degree of wear. The section that comes out first can give you an accurate picture of the state of the other sections. The sections that remain inside the tank during this inspection process ensure that the tank does not lose its sacrificial protection momentarily.
As you can see, flexible anodes offer homeowners a more user-friendly way to prolong the life of a water heater. That extra cost you incur to buy this type of anode is more than justified by the benefits that you will enjoy during and after the anode has been installed.