pex preheater

[davey]

Any thoughts?

[maple flats]

Pex, being plastic would give very poor temperature exchange. You would also have a hard time eliminating air locks (may be impossible) since the pex will not hold a rigid shape.

[Flat47]

It's do-able. Pex is cheaper than copper here. One down side is that since Pex is plastic it is more of an insulator than it is a conductor, so heat transfer would suffer.




I guess I type really slow. Looks like Maple Flats beat me to it.

[Haynes Forest Products]

Plus I wonder is you would get gassing from the Pex at the higher heat. Plus tight bends under stress will kink at higher temps.

[Flat47]

Plus I wonder is you would get gassing from the Pex at the higher heat. Plus tight bends under stress will kink at higher temps.

Could use the vapor barrier Pex - it's intended for use on closed circuit recirculating heating systems to help eliminate rust and scale in the boiler. I'm told that pvc fittings are now available for Pex, too. I haven't seen them, and the brass one are getting more expensive by the day (no kidding). But, it's easy to put together and is lead-free. I wouldn't bend it for a preheater. I'd use the available elbows.

I still favor copper for a preheater. And copper has it beat hands down for heat transfer. That's reason enough to stay with copper.