PEX FAILURE!!! What do you think was the cause?

jackrich99

I BOUGHT A 5000 SQ FT CASTLE A FEW YEARS AGO AND FOUND OUT THE RADIANT HEAT WAS A MESS AFTER I CLOSED ON IT. TO GIVE YOU SOME BACK GROUND INFO ON THE HEATING SYSTEM: THE HOME HAS 3 STORIES OF WHICH ONLY THE 1st STORY HEAT WAS INSTALLED. IT CONSIST OF 12 LOOPS OF 5/8 WIRSBO HE/PEX APPROXIMATELY 300ft to 350 ft PER LOOP RUNNING IN THE MIDDLE OF A 6 INCH POUR OF CONCRETE SLAB ON GRADE RADIANT HEAT. THIS TUBING WAS INSTALLED IN 1998 TO 2000. AT THE TIME I BELEIVED THIS HAPPENED THE HOUSE ONLY HAD A OUTDOOR WOOD BURNER AS ONLY HEAT SOURCE. I WAS TOLD BY WOODBURNER COMPANY THAT ORIGINAL OWNER PACKED THE OUTDOOR WOOD BURNER FULL OF COAL BEFORE HE LEFT TOWN FOR A FEW DAYS AND THE AQUASTAT MALFUNTIONED LEAVING WOOD BURNER FANS ON FULL BLAST AND DAMAGED THE WOOD STOVE. HE DIDNT KNOW ANYTHING ANOUT THE INSIDE OF HOUSE. DO YOU THINK MAYBE TOO HOT OF WATER CAME THRU THE FLOOR AND EXPLODED CAUSING THIS FAILURE. I HAD FIXED ATLEAST A DOZEN LEAKS LIKE THIS? AT THE TIME THIS PROBALY HAPPENED THERE WAS NO SAFETY MEASURES IN PLACE SUCH AS MIXING VALVE, HIGH TEMP LIMIT, ECT... WHAT'S YOU OPION.?

kcopp

Turn off the ALL caps.... its like you are yelling.

That is a freeze burst.... I have seen it many times. Was that just before a fitting?

Mark Eatherton

Sorry Kevin, but I disagree. Having seen PEX tubes that were melted by a run away boiler, I think these tubes were exposed to extremely high temperature and possibly pressure. That is evidenced by the clear globules near the splits. Freeze breaks don't typically show this kind of distortion. Best way to find out for sure would be to send them back to the manufacturer and ask them for their opinion. If the OP needs the name of a contact at the factory, I'd be glad to help them find a good resource.

Another thing to look at would be delamination of the EVOH barrier, if in fact it has barrier tube on it.

Bummer.

kcopp

All good. You certainly know better than I....
I ran across this this week. They claim it was a freeze. Uponor pex A

Gordy

Quite amazing how far the pex will stretch, and thin before failure. Also a different failure then the OP is encountering.

4Johnpipe

Wonder if the water flashed to steam...OP looks like melted Pex. @Kcopp looks like freeze expansion. Although if the tubing was held in suspension in cement perhaps a freeze expanded into air bubble in cement...???

jackrich99

Yes it was Wirsbo he/pex with the barrier. To answer other question most of these leaks were in the middle area of 300 foot loops. There also was one or two at the exiting of the floor going into the manifold so those ones would've been before a fitting, but most were not. The system was an open system being a outdoor wood burner so Maybe pressure shouldn't have been a factor as much, but I did find an expansion tank on the piping. Rumor is a professional radiant company in Columbus Ohio did this job but I never verified that with them so I won't be naming names. Thanks for your comments

jackrich99

I posted this because of the time I encountered this problem I couldn't find very much info about pex failure and nothing about Wirsbo failing under my conditions. EVERYBODY SAID SCRAP THE RADIANT AND PUT IN FORCED AIR. I was able to find the leaks and install gas boilers and couldn't be happier with the radiant. I am glad it all worked out or I would've got a lot of "TOLD YOU SO" from the forced air folks and wife

jackrich99

Yes Mark if you could tell me who to send that too I would definitely get their opinion but I agree with you that it was a run away boiler.

Mark Eatherton

Send it to Mark Hudoba at the Uponor office in Apple Valley Minnesota. Reference me.