Pex Tubing Temp Rating

SMITTY wrote:Interesting. Last person I talked to that used it said it was a nightmare to work with - kept coiling up like a rattlesnake. Had to feed it 120°+ water to get it to conform. Maybe there's different grades of that stuff?? Who knows ...

Good to know.

Yeah, got the first batch from Pexsupply,, don't remember the brand , needed a 100 feet more to finish the job, got that from Home Depot, not as good, it was hard to work with. It all is but its worth it, you run it like wire, bend it around corners up into walls, ect, no torch and solder, no right angels and its cheep.. it has a life of about 120 years.. I'm done with plumbing..

Yeah you and me both!

Wow .. impressive!

Keep in mind that PEX for water lines, even DHW, is quite different use than for a boiler. I am definitely sold on the 'plumbing' benefits of PEX- True PEX, not that (often white) plastic where you expand it and count on the elasticity of a pex ring to hold it on.

I use a good copper ring crimp pex quite often for plumbing. I used Propex brand brass connectors for theNG boiler's hydronics install. I feel much better about the secure connection it makes. The tool was pricey, but after renting one years ago, I found one used that was just the ticket. Need some strong arms in some tight spots

If you do use PEX for hot water (DHW or hydronic), be sure to support it properly. It WILL get softer as it heats and can sag.

For curves, they have a nice plastic clipon piece that holds the pex in shape and prevents kinking.

FYI. For hydronics, you MUST use oxygen barrier PEX. The stuff I've used looks like a white lining inside the red tubing. If you don't, you can have lots of rust problems with your boiler and components.

Great info there - thanks!

Learn something new every day! But, I'm still done with plumbing ... at least until I have to fire the oil boiler up again. Maybe I'll keep the stoker going all summer ...

Just heads up on my post. I was looking for a pic of the fittings to show you for hydronics, but am having trouble finding one. The fittings I used have a brass ring that slides on the pex first, you expand the tubing, insert the fitting, then use the 'fork' kind of tool to force the brass ring over the pex where the fitting is installed. It locks the tubing onto the fitting.

If I find a pic, I'll post it. BTW, I don't have a fancy power tool for it, just a manual one.

Smitty, IIRC those plastic radius curve pieces can be snapped onto already installed pex. The larger diameter tubing seems to need it more than the smaller tubing. Nice install you have there. PEX is kind of 'fun' especially if you are using the ratcheting cutters. No glue!

Sounds a bit easier than soldering. Probably quicker too with all the sanding, fluxing, heating ....

SMITTY wrote:Still not sold on that stuff. Copper's tried and true for over 100 years. Expensive, yes - but it works. Keep the plastic where it belongs - wrapped around a baloney sandwich.

smitty once you use pex you will never go back...... another good thing about pex is that the acid from the coal dust will not rot out the piping .... starting to have that problem now on my stoker, a lot of the copper in the mechanical room is getting pin holes in it from the dust,

Rob R. wrote:

SMITTY wrote:Sounds a bit easier than soldering. Probably quicker too with all the sanding, fluxing, heating ....

Making the connections is easier, but you have to support the pex much better than rigid pipe like copper.

When sweating copper, If the fittings are clean, properly fluxed, and you heat it evenly with a good torch...chances are good that you will end up with a nice fitting. If you are in a hurry, use crappy flux from the big box store, and have a pencil flame torch with a big tank that limits the movement of the torch...get ready for leak city.

RAYJAY wrote:a lot of the copper in the mechanical room is getting pin holes in it from the dust,

Any chance the pinholes are near fittings or that you have acidic water?

no its pin holing from outside in not on a joint, just where ever you get a chunk of coal dust it will pin hole I blow the room down now wit a fan in the window it helps,

but 2nd owner on house so some of the damage is all ready done..... thank god for shark bites ..lol there a good bridge till you can fix in the summer

RAYJAY wrote:

Rob R. wrote: Making the connections is easier, but you have to support the pex much better than rigid pipe like copper.

When sweating copper, If the fittings are clean, properly fluxed, and you heat it evenly with a good torch...chances are good that you will end up with a nice fitting. If you are in a hurry, use crappy flux from the big box store, and have a pencil flame torch with a big tank that limits the movement of the torch...get ready for leak city.
Any chance the pinholes are near fittings or that you have acidic water?

no its pin holing from outside in not on a joint, just where ever you get a chunk of coal dust it will pin hole I blow the room down now wit a fan in the window it helps,

but 2nd owner on house so some of the damage is all ready done..... thank god for shark bites ..lol there a good bridge till you can fix in the summer

Have you tried using the (cheap) pipe insulation? BTW, you should be using the thicker copper piping for hydronic runs (m/l)

I won't use pex. If I'm doing a rental on the cheap (potable water) I use CPVC (even then I hate it) or I use Cu or Fe. Stanless steel is another option for potable. I Hate pex, it's cheap-looking, it's ugly, it's made for people who can't sweat copper or fit a pipe and most insalls are so sloppy it's awful. Did I mention I hate pex?

Another thing I REALLY don't like is "Propress" type fittings. Most of the expense and screwing around of Cu, but none of the permanency. I dislike these for two reasons - 1. O rings won't last, they will fail, they will leak, Shark bites are a better design than these. 2. It's a way to cut labor costs, so now, instead of hiring someone who's competent in sweating Cu, you can hire an idiot who can work a crimper.

Berlin wrote:I won't use pex. If I'm doing a rental on the cheap (potable water) I use CPVC (even then I hate it) or I use Cu or Fe. Stanless steel is another option for potable. I Hate pex, it's cheap-looking, it's ugly, it's made for people who can't sweat copper or fit a pipe and most insalls are so sloppy it's awful. Did I mention I hate pex?

Another thing I REALLY don't like is "Propress" type fittings. Most of the expense and screwing around of Cu, but none of the permanency. I dislike these for two reasons - 1. O rings won't last, they will fail, they will leak, Shark bites are a better design than these. 2. It's a way to cut labor costs, so now, instead of hiring someone who's competent in sweating Cu, you can hire an idiot who can work a crimper.

Haha. Tell us how you *really* feel Kidding. I like really like pex for plumbing, good for hydronics in controlled heart systems, but differing opinions - even strong ones- can give good input.