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General Plumbing and Gasfitting Talk => Plumbing => Ask Plumbers (Trade) => Topic started by: Rodza1 on September 23, 2012, 01:02:11 PM

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Title: HJ Coopers Duplex S/Steel solar/wetback ready Mains Pressure HWC queries
Post by: Rodza1 on September 23, 2012, 01:02:11 PM


Hi Guys,

Im looking at doing a upgrade of hot water heating shortly for family. Im looking at a HJ Coopers 250L MP duplex s/steel cylinder. Their current LP 180L electric HWC is on the way out.

Im after a 250L duplex s/steel model with a 3kw element, an indirect wetback coil so I can do a nice LP setup for their wetback on a PRV/open vent and also it needs to have solar connections as they wish to add solar panels in the future, direct feed though, not a secondary coil. Ive been quoted about $1900 inc gst. Is this a reasonable price?? It sounds ok to me but I really dont know. They will be primarily be using just the element for their hot water heating needs but want the wetback circuit ready to go in case of power cuts etc as they do occur occasionally in their area.

Havnt ordered it yet but have been wondering what the quality of HJ Coopers s/steel cylinders is like as I have heard stories that they crack due to constant expansion and contraction of the s/steel. I have put about 10 in already over the last four years only ever having heard of one in that 10 ive installed that failed and had to be replaced under warranty. Its been a while since I have put one in, at least a year now and cant quite recall what they are like. Some friends who are also plumbers are also a little sceptical as have had issues before.

Does anyone know if they are still doing the 20 year warranty for the solar/wetback HJ Coopers models?  I have looked at some of the models listed in the new products section of this website but am unsure which model is the one I am after.

If anyone has any alternative options that I havnt considered I would be open to suggestions, looking to make a decent system that will last them many years.
Last thing I want is for my installation to fail in only a few years. What are the superheat/peter cocks/greenglo/triumph cylinders like??

Also are steel enamel lined cylinders with sacrificial annodes really that bad?? Even if the annode gets replaced every couple of years?? All I know is the enamel lining/coating cracks internally after years of heating cycles, exposing the steel cylinder to corrosion and eventual failure.

Looking forward to getting some good feedback

Cheers