Immersion Chiller Materials

[Nodrog]

Has anyone any experience in using PEXAL type pipe for immersion chiller coils?

Seems as if it would have similar heat transfer to copper, but being plastic coated should be cleaner / easier to clean?

PEXAL is a thin aluminium pipe with a plastic inner and outer barrier sheath, its used for hot and cold water plumbing.
there are lots of different brands, this is an example:
http://www.uk-plumbing-supplies.co.uk/about-the-pipe.htm

I think the fittings can be expensive, but the pipe cheap, and for an immersion chiller don't really need any fittings, just hose pipe on the ends.

anyone else tried it?
or
http://www.pexalaustralia.com.au/

 

[NickB]

Would personally be checking that they're food grade on the outside of the pipe...

Cheers

 

[Nodrog]

PEX is used for domestic water plumbing, hot and cold, so have no concerns about that.

 

[T.D.]

Will the plastic coating on the outside withstand boiling wort though (household hot water is much cooler)? And if so, it may end up effectively insulating water in the coil from the wort...

 

[Yorg]

I would not be surprised that it is somewhat thermally insulative rather than conductive. It is not desigbed for boiling is it? There is no reason to assume it is food safe outside its design specs.
Further, why are you considering it - is there a reason you want to use this rather than copper?

 

[Nodrog]

mainly cost, and I thought easier to clean, the crowd seems to be against it though!

 

[Wolfy]

Not against it - as such - however it's something 'new' that you've not proved the advantages of using, and there are many unanswered questions:

Is the outside of the pipe food safe - just because the inside is does not mean the outside also is?
Is the plastic food safe at boiling temps, again just because it's been used for hot water temps does not mean it's food safe at boiling point?
Is it actually a good thermal conductor (sure Aluminum is, but with two layers of plastic what would it work like in practice)?

 

[stew.w]

i dont think it would be anywhere near as good as cooper for heat conduction.
we use pex for all the water services at work and it is reasonably thick wall pipe.
its cheap, fittings arent.
also plastic water pipes have stuff to stop rats eating them (not that it works)
so theres no way i'd be using it in boiling wort.

cheers,

stewart