# heat pex for boiler install



## timrath (Sep 28, 2013)

I have been doing lots of hot water boiler installs and I was thinking of using heat pex instead of copper for installs. We always used copper anybody ever trying using heat pex for a hot water boiler install? Any downsides or problems


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## Burner tech (Oct 24, 2013)

You need to take into consideration the heat ratings on pex, I believe it says 200 degrees but don't quote me as I have never used the stuff. Consider the heat you will produce, and the expansion and contraction. Personally I would not recommend it.


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## timrath (Sep 28, 2013)

I looked up ratings on heat pex and 80psi at 200 degrees F


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## redbeardplumber (Dec 4, 2012)

You mean for the high temp piping.??

Personally only for the infloor piping or floor warming.


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## MTDUNN (Oct 9, 2011)

Yes on floor heating. That's was the original intent for pex I do believe


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## love2surf927 (Dec 22, 2011)

Straight from the Uponor manual, and it was designed for in-floor heating as was said and it's been in use for quite some time. Which was surprising to me out here in Southern California because it has only become popular out here for a few years. I think they approved its use here in 2009, someone correct me if I'm wrong.


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## wyrickmech (Mar 16, 2013)

love2surf927 said:


> Straight from the Uponor manual, and it was designed for in-floor heating as was said and it's been in use for quite some time. Which was surprising to me out here in Southern California because it has only become popular out here for a few years. I think they approved its use here in 2009, someone correct me if I'm wrong.


you guys are behind the times it's been around here sense mid 90s


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## MTDUNN (Oct 9, 2011)

wyrickmech said:


> you guys are behind the times it's been around here sense mid 90s


Please enlighten us


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## wyrickmech (Mar 16, 2013)

MTDUNN said:


> Please enlighten us


about what I simply stated we have been using uponor For radiant heat sense the mid 90s. It has been approved here for everything domestic and heating sense.


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## redbeardplumber (Dec 4, 2012)

Here as well, I think the OP was using it instead of copper, for the boiler piping????


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## rjbphd (Feb 5, 2010)

Did ya hear about the the lowballer got the job and piped the steam boiler with scd 40 pvc???


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## redbeardplumber (Dec 4, 2012)

Your kidding right?!


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## rjbphd (Feb 5, 2010)

redbeardplumber said:


> Your kidding right?!


No.. true story... happened on east coast about 15 years ago


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## redbeardplumber (Dec 4, 2012)

What happened. Everything melt. Lol. Did it last a week?


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## wyrickmech (Mar 16, 2013)

rjbphd said:


> Did ya hear about the the lowballer got the job and piped the steam boiler with scd 40 pvc???


 that didn't last long


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## rjbphd (Feb 5, 2010)

Okay, if I remember it right from reading one of Dan Holonan's heating stories.... this heating guy been taking care of this old lady's boiler with oil burner which on its last leg for years. Finally, the lady asked for the replacement qoute.. weeks went by and colder weather coming soon... he called her about the job.. she said she found someone to do it cheaper by 1500 bucks and called him a low life thief....

Thanksgiving came and he got a frantic phone call from her to come out and fix the problem with the steam coming out of the basement.. asking where the lowballer was.. wouldn't answer the phone.. so he went out there and she's right, the steam was coming up from the basement so bad that he couldn't enter, went outside and pulled the electric meter to kill the juice..

Upon entering, found the boiler piped in pvc, melted.. and steam was blowing out of it while the low water cut off kept feeding water while the system running to meet pressure..

Why did it lasted this long?? Unseasonly warm fall til the first cold snap..

With all that steam in the house, water and moisture damages to wallpaper and among other things.

Moral of this story, do not ever let a plumber do a boiler replacement.. get a real hydronic heating guys(gals) to do the job.


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## MTDUNN (Oct 9, 2011)

I repiped a heat exchanger last spring. It had PVC in stainless.


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## rjbphd (Feb 5, 2010)

MTDUNN said:


> I repiped a heat exchanger last spring. It had PVC in stainless.


Huh??? Pvc in stainless?? U mean pvc connected to heating exchanger??


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## MTDUNN (Oct 9, 2011)

Yes, the homeowner had some idiot connect PVC on a pool heater. Had 2 stainless heat exchangers connected to his oil fired boiler


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