Using Pex for condensate return?

heatbabe

I have a one pipe steam system. Can I run a return for the condensate using pex tubing?

nicholas bonham-carter

Different return

If the return is at floor level, and therefore well below the waterline height of the boiler, you could run the return in any number of materials, as long as they can put up with the temperature. If you choose pex, then I would go a size or two larger, as the fittings have smaller diameters, and of course there would be no pressure apart from gravity to force the water along faster. In a pinch, on a small system, even hot-water rated garden hose could be used.

Make sure you up your venting, so that you don't have a vacuum collapsing the pex or hose as the boiler shuts off. Let us know how long it lasts.--NBC

lza

Pex

The first thing I would do would be to check with the manufacturer for temperature rating at continuous operation. 



But personally I would cringe at seeing pex used as a condensate line.  It will expand dramatically, bow and droop, and  look completely unprofessional.  But if can't afford to do it in Schedule 80 steel pipe and cast iron or 300 pound malleable iron fittings, what can you do?

Dennis Foley

No

check the ratings. I removed Pex from a hot water loop that someone had taken from a steam boiler heat ex-changer. The Pex didn't fail, but it was in really bad shape and no longer provided the flow needed. I will probably shrink in length, and if your aren't above the temperature rating, you will be at it. Plus it will look like..........