Why did my hot water tank rust so quickly?
Tuesday, December 30th, 2008That’s a question I’ve been asked so many times I’ve lost count.
The hot water storage tank used in most hot water systems, made by the major manufacturers is made of mild steel for strength. The tank then has a coating of vitreous enamel on the internal surface. The purpose of the vitreous enamel lining is to separate the stored hot water from the mild steel cylinder. This vitreous enamel lining protects the steel tank against corrosive action by the water.
A sacrificial anode rod is also incorporated in the tanks manufacture for extra protection. The anode will immediately start to corrode away over a period of years instead of the tank thereby extending the life of the tank using “cathodic protection”.
This is a quote from rheem’s web site about how “Cathodic protection” works.
(When two dissimilar metals are connected together and are both in contact via an electrolytic solution, a weak electric current is formed. This weak current produces a cathodic/anodic reaction between the two metals. Therefore, one metal will corrode in order to protect the second metal. The atoms of the less stable metal form a protective coating over the more stable metal.)
The original anode will only last about 5 years in a standard tank, or for about 9 – 10 years on an “OPTIMA” tank (Rheem’s deluxe model). The optima has a heavy duty anode & also has a double lining of vitreous enamel for added protection, however after this time is up & the anode has completely dissipated away, the tank then starts to corrode internally & at a greatly increased rate because the cathodic protection has gone.
So what can we do about this? Simple, by replacing the anode you can greatly increase the life of your tank, even if the tank is up to 6-8 years old, or 10-12 years old for the deluxe or “OPTIMA” models. I am offering a complimentary (Obligation free) inspection of all anodes whilst on the job, if required you have the choice of replacing it or leaving it till later, or not at all. IT’S YOUR CHOICE. If you decide to replace it the costs are approx $110.00 for standard tank, or $132.00 for deluxe or Optima models (Applicable while on the job for tanks with adequate access, or P.O.A. for low ceiling heights or reduced access) For return trips at a later stage or by appointment $132.00 & $154.00 respectlively.




