Pex run inside 1 and 1/4 iron

Coffem

Here's one for you...



Second floor conversion from steam to hot water. Currently, or, previously there was single pipe steam run from basement boiler to second and third floor.



The challenge of course is always getting the piping up there. We have an idea to snake 1/2 inch pex (times two for feed & return) inside the existing single pipe and then connecting the pex to rad as supply/return. So far seems like the two pex will fit, but worry a bit about the abrasiveness inside the old iron.



Bet this is unique, ideas???

Steamhead

"abrasiveness inside the old iron"

is reason enough not to do it this way. You couldn't guarantee it wouldn't leak.



Best thing is not to convert it at all.

Charlie from wmass

No

others have tried but often it is not advised as how are you going to hold up the pipe never mind the expansion of the pex rubbing every time it warms and cools.