Non-Barrier Pipe, New boiler, Stainless or Cast Aluminum Hex

10 Jun 2009
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United Kingdom
Having a new boiler fitted to replace my old cast iron Ideal, I have non-barrier plastic Hep so am expecting to have system corrosion caused by the oxygen infusion. To minimize problems with the boiler should I go for a boiler with a stainless steel or cast aluminum heat exchanger?

Looking at Vaillant ecotec plus 415 / Wocester Greenstar 12RI

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Get the non-barrier replaced, preferably with copper, or it will screw your system and any boiler.
It is more effective to find a good installer and let him advice you on the project, than trying to learn all the facts in order to tell the installer how to do his job.
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The stainless steel boilers are more expensive to make.

The ali ones are cheaper and so usually sold a bit cheaper.

The main problem with oxygen in your system will be rusting of the steel rads.

The best advice is to replace the pipework!

There seems to be little experience of non barrier pipe problems and its probably very variable with differing levels of inhibitor addition.

Suffice to say there are a few non barrier pipe installations and they are working. However, they are not recommended.


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