Bowen household to CRA 15.5.16

Constant cylinder element failure


Good Evening,

I have been suffering repeated element failures in a Hot Water Cylinder installed in 2011 as an EQC earthquake repair – I think we are up to element set # 15.

I am reluctant to accept that this is a problem just at our house, and I am keen to know if any other residents in the Southern suburbs of the city are having similar problems. EQC staff have indicated they are really interested in finding a solution but keep doing the same thing – getting me to pay for the installing of new elements – and expecting a different result. All the plumbers seem to be aware that there is a problem with the water in Cashmere, but no-one at the CCC wants to talk about it.  What can you tell me about this matter?

CRA committee member responds: We understand it’s not only Cashmere, that plumbers are now talking of effects city-wide. It is mainly mains pressure units. [CRA invited an article be posted, which follows]

Is anybody else having these problems with their Electric Hot Water Cylinder elements ….?

We live up the top of Bowenvale Avenue. In September 2011 we had a hot water cylinder (HWC) replaced by EQC as part of their earthquake repair programme. Since installation the elements have needed to be replaced every three months or so as they are being damaged by severe corrosion and they ultimately fail. The elements in use at the moment are due to fail, based on previous experience, in the coming weeks. The cylinder supplier and the plumbers that undertake the installation of replacement elements are amazed at the nature, extent and speed of the corrosion. Some people I have spoken to about this say that Cashmere, and areas in the south of the city, are prone to failures of this nature – at the moment that’s hearsay.

So, what do I know from my investigations;

  • The Cylinder manufacturer is adamant that it is not the cylinder causing these failures – citing that there are thousands of these, and similar units installed in homes around the country.

  • An element manufacturer in Auckland has been sent a set of failed elements, and they are equally assertive that their product is entirely satisfactory, and the failures are not in any way linked to poor quality materials or low manufacturing standards.

  • The electrical supply and connections are correct, and the circuits have been checked twice for continuity.

  • The City Council advise that the water is not causing these element failures.

  • We have installed probably every type of element appropriate for the application and there is no significant difference in the time between installation and failure.

I can’t believe that this situation is unique to our property and I am keen to know if any other homes have experienced similar failures / problems with their Hot Water Cylinder elements. It is now May 2016 and we are up to element set number 14 I think. Our Peter Cox Silver Bullet cylinder is showing signs of degradation, with weeping from some outer casing rivet points and water in the drip tray. Please ask around your neighbourhood to ascertain whether anyone has experienced similar element failures, and if so ask them to post their story on this site.



CRA responds 23.6.16:

We are working closely with Christopher to resolve this. Today we met onsite where plumbers were checking a sacrificial anode and cylinder element after two months in place (see pic). Will these last longer than another two months? Cleaning scale from the element will extend its life but shouldn’t be necessary at $200 labour each time. EQC were there too and are committed to returning normal hot water service, but what is the permanent fix? Christopher now has a scraping sample of the scale to be tested. (History of fault is in the following table.)