# Freezing pex pipe



## sparky (Jan 8, 2014)

Got a customer that has a wirsbo pex line running across his attic that is heavily insulated but yet it still freezes over by the eve,my question is can we wrap pex pipe with heat tape???i never done that before and was not sure if it is safe to do so.any thoughts????tips????thanks:thumbup:


----------



## Nealfromjpt (Oct 10, 2012)

we have some BowPex with heat tapes on them and had no issues with it.
BowPex is rated for 180Deg temps


----------



## HSI (Jun 3, 2011)

Has it split from freezing?


----------



## sparky (Jan 8, 2014)

HSI said:


> Has it split from freezing?


No,not yet,he just can't use it while it is frozen,was thinking about taking the pex pipe out and replacing it with copper and heat tape,but would rather wrap the pex line if it is doable!!like I said I never have put heat tracer on pex pipe


----------



## Dpeckplb (Sep 20, 2013)

I had a contractor wrap a 1" poly line with heat wrap. It melted a hole in it and it flooded the crawl space.


----------



## HSI (Jun 3, 2011)

I would call the local rep and ask for the info in writing. That way you have a selling point for copper if you can't trace it or if you can and a problem comes up your covered. Local supply house should have the rep info.


----------



## rjbphd (Feb 5, 2010)

Why is the pipe installed in freezing area??? Failed the in plumbing class 101


----------



## saysflushable (Jun 15, 2009)

1. you better find heat tape that is rated for indoor use.
2. you better find heat tape that is rated for indoor use.
3. I see pex with heat tape on it all the time UNDER mobile homes


----------



## Plumberdood1 (Apr 23, 2014)

Same here. See heat tape on black polly and pex under trailers.


----------



## SchmitzPlumbing (May 5, 2014)

cant you insulate the attic? when i have to run a line in an attic, (only for a ceiling mounted shower head), i run the pipe close to the drywall ceiling, box it in with 2" foam so it can get heat from below, and blow in insulation over the top. it wont freeze. heat tape is a fire hazard.


----------



## Master Mark (Aug 14, 2009)

just get a run of that braided cable type of heat tape and put it to the pipe then the insulation it will work fine.....

Wirsbo will not break from freezing, I KNOW that for a fact


----------



## sparky (Jan 8, 2014)

rjbphd said:


> Why is the pipe installed in freezing area??? Failed the in plumbing class 101


It was side porch that was covered over and this was only way to get water over to the area


----------



## sparky (Jan 8, 2014)

I'm with you all here,I think any type of heat tape in an attic is nothing but a fire hazard waiting to happen,I'm gonna recommend that he insulate the attic and see what happens


----------



## SchmitzPlumbing (May 5, 2014)

i think of heat tape in an attic like knob and tube wires. if you cover it with blown in insulation, it can start a fire. knob and tube needs open air so it doesnt over heat. i wonder if heat tape is the same?


----------



## Redwood (Sep 8, 2008)

Master Mark said:


> Wirsbo will not break from freezing, I KNOW that for a fact


I know otherwise for a fact...:laughing:










In fact I will tell you that it is very unlikely that PEX will split from freezing...
*Unless...*
There is metal fittings between 2" & 7" apart...:yes:


----------



## sparky (Jan 8, 2014)

Redwood said:


> I know otherwise for a fact...:laughing:
> 
> 
> 
> ...


Yes I have ran across some zurn pex pipe that had froze and split back last January when that blast of arctic air hit ky,couldn't figure out why it had split but now it makes sense as it was between two brass fittings about 4" apart!!!

Also didn't you tell me red that I could crimp my zurn pex fittings to wirsbo pipe and it be alright???i had been transitioning with shark bites but will crimp it if it doable


----------



## Redwood (Sep 8, 2008)

sparky said:


> Yes I have ran across some zurn pex pipe that had froze and split back last January when that blast of arctic air hit ky,couldn't figure out why it had split but now it makes sense as it was between two brass fittings about 4" apart!!!
> 
> *Also didn't you tell me red that I could crimp my zurn pex fittings to wirsbo pipe and it be alright???i had been transitioning with shark bites but will crimp it if it doable*


Yep it works fine...
Your Wirsbo Rep will have all sorts of things to say why you shouldn't though...

Truth be told...
Do you think plastic pipe will ever pay full compensation for a defect? :laughing:
:no::no::no::no:
What have you got to lose?


----------



## Master Mark (Aug 14, 2009)

Redwood said:


> I know otherwise for a fact...:laughing:
> 
> 
> 
> ...




Redwood, THANKS for the pictures.... I have never seen this before

we had a whole house freeze solid and I was amazed there was no breaks.... 

soo....are these breaks got something to do with the small section of pipe involved???


----------



## Redwood (Sep 8, 2008)

Master Mark said:


> soo....are these breaks got something to do with the small section of pipe involved???


Right! The Pex freezes first at the 2 metal fittings then starts freezing towards the center. The volume of freezing water, the expansion rate when freezing, is just enough to exceed the ability of the Pex to expand when the distance is between 2-7 inches.

Somewhere here there is a link to the study that I had read that had this info. It's here somewhere you can trust me on that... :laughing:

I'll let you find it...

It was commissioned by an HVAC Organization and the 2-7 inches is for plain Pex all brands, pex-al-pex used in heating applications didn't do well with any freezing at all, as would be expected...


----------



## Master Mark (Aug 14, 2009)

Redwood said:


> Right! The Pex freezes first at the 2 metal fittings then starts freezing towards the center. The volume of freezing water, the expansion rate when freezing, is just enough to exceed the ability of the Pex to expand when the distance is between 2-7 inches.
> 
> Somewhere here there is a link to the study that I had read that had this info. It's here somewhere you can trust me on that... :laughing:
> 
> ...



I will trust you as far as I can throw you....:laughing::laughing:


a small section of pipe like that must the the exception to the rule 
because I have seen whole houses frozen solid only to watch it thaw
out and be ok.... Of course a small section of copper would also make a sizeable crack too if frozen solid..... 

so what does it all mean in the grand scheme of things for a lowly plumber like myself to ponder...?????? :blink::blink:

..??????[/SIZE]


----------



## dhal22 (Jul 30, 2010)

Wouldn't the Raychem design work fine in an attic situation? The heating reaction only occurs when the temp gets to a certain position. The reaction stops as the self made heat warms the cable. Reaction may not be the correct term.


----------



## sparky (Jan 8, 2014)

dhal22 said:


> Wouldn't the Raychem design work fine in an attic situation? The heating reaction only occurs when the temp gets to a certain position. The reaction stops as the self
> 
> made heat warms the cable. Reaction may not be the correct term.


I really have no clue to be honest with ya,I have decided that I'm not gonna wrap any pipe in that attic and be held responsible when it burns down and kills someone,gonna tell the ho to put much more insulation in whole of attic,esp. Around the eves


----------



## rjbphd (Feb 5, 2010)

sparky said:


> I really have no clue to be honest with ya,I have decided that I'm not gonna wrap any pipe in that attic and be held responsible when it burns down and kills someone,gonna tell the ho to put much more insulation in whole of attic,esp. Around the eves


If ya piped my way.. it won't freeze... think hydronic heat..


----------



## Cajunhiker (Dec 14, 2009)

If the attic is cold enough to freeze and break PEX pipe, the home prolly has a lot of serious issues.


----------



## sparky (Jan 8, 2014)

Cajunhiker said:


> If the attic is cold enough to freeze and break PEX pipe, the home prolly has a lot of serious issues.


he said the pipe hasnt ever cracked or busted as it is one continous run with no fittings around where it freezes at,it just freezes up i guess when the wind hits it just right.:laughing:


----------



## sparky (Jan 8, 2014)

rjbphd said:


> If ya piped my way.. it won't freeze... think hydronic heat..


since the slab was already poured and this was a porch at one time,i assume this is the reason the original plumber ran the line this way,as it was the onlly way to get it over to where it needed to be without running it across the finished room.:laughing:


----------



## rjbphd (Feb 5, 2010)

sparky said:


> since the slab was already poured and this was a porch at one time,i assume this is the reason the original plumber ran the line this way,as it was the onlly way to get it over to where it needed to be without running it across the finished room.:laughing:


Def not a hydronic heating guy here....


----------



## sparky (Jan 8, 2014)

rjbphd said:


> Def not a hydronic heating guy here....


Nope,I run potable water systems:laughing::laughing:


----------



## Redwood (Sep 8, 2008)

Cajunhiker said:


> If the attic is cold enough to freeze and break PEX pipe, the home prolly has a lot of serious issues.


LOL Come on up...
Here the serious issue would be some dumbazz ran pipes in the attic...
Attics & Exterior walls are pretty much off limits...


----------



## fhrooter72 (Apr 12, 2011)

Redwood, Based on the pics you posted, it seems the PEX was improperly installed. Uponor requires a minimum of 8" between fittings to allow for expansion if the pipe freezes. Houston rarely has freeze issues but, I filled a 12" section of pipe and capped both ends and left in my deep freezer for a week to see what would happen and the pipe expanded but, no leaks.


----------



## Redwood (Sep 8, 2008)

fhrooter72 said:


> Redwood, Based on the pics you posted, it seems the PEX was improperly installed. Uponor requires a minimum of 8" between fittings to allow for expansion if the pipe freezes. Houston rarely has freeze issues but, I filled a 12" section of pipe and capped both ends and left in my deep freezer for a week to see what would happen and the pipe expanded but, no leaks.


Those were from a test commissioned by some HVAC Industry Association several years back...

They tested many different types and brands of PEX with a variety of lengths between fittings, subjecting them to numerous freeze thaw cycles. The consensus was other than PEX-AL-PEX which failed to have any freeze damage resistance, that no brand of PEX was immune from suffering freeze damage, when metal fittings were used and spaced between 2" & 7" apart. That includes Wirsbo/Uponor....


----------

