latest on insulated pex small diameter?

archibald tuttle

We will be opening chases for some wiring in a house that was originally piped in insulated copper to serve fan coil units with hydronic heating and cooling. The pipes were well insulated with slide on armaflex which was carefully glued at joints, tees, etc. Performed well for a decade and then as the armaflex dried and degraded joints opened up and we have numerous nuisance condensation problems.

My thought is to replace the copper with a 'home run' style pex setup, e.g. 1/2" pex with continuous insulation feed and return individual to each fan coil all the way back to the boiler room.

I bought a 125' roll of armaflex and experimented with a couple first floor units that could be easily accessed from the basement and it worked like charm.

Some runs to upper floors could end up as long as 60 feet and I think it might be delicate to pull pex that long through the armflex so I'm wondering about the availability of preinsulated products at least for the longest runs. Has anyone tried this before, maybe I'm over engineering and I could actually lay out a 60 ft. straight length of armaflex and get an electrical fishtape though it and then pull the pex.

The ecoflex and insulpex have some orientation towards burial and tough service and they look really expensive but maybe the ecoflex with feed and return would be rational way to go given labor savings. What is this stuff running per ft with 2 1/2" pipes in the jacket?

Are there other lower tech (read lower price) products that essentially amount to pex presinserted in armaflex of some similar approach?

Thanks,

Brian

william_5

pex

we run oil lines through armerflex some things i have found is we use a few droops of oil on the in side of the armerflex as well as the out side of the oil line lay the armerflex down straight with some one holding the other end tight you would push the pex through any bends and you hade it. hope this helps

william

Dirty Hands Dale

eco flex

I have installed ecoflex only once before, it had a strong memory.

It might be a bear to install if it keeps jamming up and you can not get to that part of the chase.

Larry Weingarten

I've had...

... very good luck getting long lines through conduit by hooking up a shop vac to one end and pulling a strip of cloth on a fishing line through. I then use the fishing line to pull a small rope back. The rope then pulls your PEX. I've done up to 600' so far. If the insulation were a loose fit on the PEX it might help.

Yours, Larry