flex tubing vs. copper pipe for baseboard heating

[hotgastruass]

Anyone's thoughts on this. Is the flex tubing only rated for 180degree water....is this an issue for baseboard heat. I have never worked with this stuff. What are the pros and cons of this stuff. Obviously its more flexible and easy to run. I figure less fittings = less leak possibilities. Do the fitting connectors for this flex tube leak easily?

[johnsp]

Most are only rated for 180° @ 50psi. Since your system should be at around 15-20 psi, it can handle up to 200° without issue. PEX gets limp as a wet noodle, especially at high temps so the tubing needs to be well secured and protected from nails when run inside walls. (Don't forget to insulate hidden tubing.) I think it's much better for main distribution trunks between floors with long runs that will cut down on joints and where retro-fitting requires the flexablity. Using short sections of PEX between BB's on the same zone might get expensive as the transition fittings are expensive.

[vern p]

Just to add to it, the standard test for hydronics in most codes is 100psi for 30 min. Don't think pex alone will stand up for this.

[tinman]

I've used it a few times. Regular pex must be well supported and secured. A better product is alumi-pex. This is a pex with a layer of aluminum. I prefer stadler products.

[hotgastruass]

ya john your right.. i have like 200ft. of copper i have to use up anyways.. id rather use that between bb than buy more of those 5$ fittings.. or whatever they are..I just hope the supply house can lend me the tool to put together the cast iron bb..I hear that tool runs about close to 500.00 I mean i could figure it in but.. id rather borrow one.. I dont want to kill this guy on the labor $$ he's a good contact and refferal. That means more to me than a tool ill probably use once every 5 years.

[casturbo]

Personally, I hate that PEX tubing. It looks like crap, sags all over and has loads of fittings that is no where as strong as a copper solder joint. To me, anything that is put in because it's the cheapest way to go is bull. What happens when someone years from now puts in some chemical in the heating system (for whatever reason) and the PEX plastic hardens and splits? Copper will never do that.