Hey everyone.:) Just watched an episode of this old house where they used pex-al-pex pipe running from the boiler to the radiators. I have the same heating system where the boiler pipes hang low from the basement ceiling. I want to eliminate those pipes and was wondering can pex-al-pex pipe be used in this situation? I reside in Chicago Ill. Where the bears are going to beat the packers.:) If so, is this code in Chicago?

Thank you guys for your input.
And thank you ask me help desk.

Do you have a steam system or a hot water system. If steam, then no, but if hot water, yes pex can be used to supply the registers, as pex is rated for up to 200 degrees, and the boiler will operate at 180 for baseboard heat. Make sure to get pex that is rated for hot water heat applications with at least 200 degree rating. We still run all of our lines in copper, but pex is allowed in my area. Good luck and hope your project goes smoothly. Also, check local codes to make sure it is allowed in your area.

PS. Ill say it again, do not use pex on a steam system. I believe the show you saw was converting steam registers to hot water registers.

Pex seems to be code everywhere, but there's more code pertaining to it, so ask your inspector on the phone.
It's red in the coiled lengths, but you can get gray in short lengths where it will show if you want.
1/2" is pretty bendable but 3/4" is tougher so you do need fittings at the turns.
A friend just installed Runtal rads for me and they take 1/2". Beautiful works of art, super thin, and super heat (but expensive).