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Radiant Floor Heating/fill radiant slab to hold the PEX down until frozen


I'm building a wood working school and wanted to have in floor heat.  The concrete contractor and I agreed putting water in the system would help hold down the Pex.  It worked fine but I forgot to remove the water exposing the slab to a full winter of freezing Colorado weather before the walls went up.  Finally finished the system the other day only to find the water I'd forgotten.  The system 1200 feet 5 zones will hold no pressure.  Remedies discussed already over pour of 2 inches, wood floor with Pex underneath, grooving the existing slab and installing a new set of zones.  I guess my question is, is there any repair technique where the pipe can be repaired in situ?  I feel there is not after 2 weeks of research but it never hurts to ask.  Thanks for your time Anthony.

Badger Boiler Service PEX slab repair
Badger Boiler Service  
There in not now, nor has there ever been a good reason to test or charge a hydronic radiant floor PEX system with water before pouring concrete. We use air, before and during the pour.

Once a hydronic radiant slab has been frozen one can only thaw and pressurize it to check for leaks. By isolating each loop you may find one or more loops still sound (30psi is usually sufficient). Sometimes you will have enough to heat the space. Sometimes you will find a few leaks that can be excavated and fixed.

If the system must be abandoned then PEX can be fixed to the old slab and concrete or gypcrete poured over all.  

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Morgan M. Audetat


Radiant panel heating design, including floors and ceilings, European wall panels and snow melting for residential and light commercial buildings..............................................................-Master of Steam and Hot Water,City of Minneapolis....................................................--- Master Plumber, State of Minnesota...........


30 years..... Charter Board Member - Radiant Panel Association, former manufacturer of condensing boilers, former national distributor of radiant floor products, son and apprentice of mechanical & plumbing contractor. Current mechanical/plumbing contractor specializing in hydronic based, integrated HVAC systems. Radiant floor heating/cooling. Snow Melting. Condensing Boilers. Indirect water heaters. System design, consulting and technical training world-wide. Licensed contractor, designer, installer and consultant.

B.S. University WI 1981 CONTINUING EDUCATION: Viessmann Condensing boiler and Solar water heating certification 2010, N.D.S.U. Lead Worker RRP certification 2010, Knight condensing boiler certification 2009, Wrightsoft Manual J CAD certification 2009, RPA Designer & Installer Certification 2008, Nate Hydronic/Forced Air Certification 2008, Uponor/Wirsbo advanced design school certification 2007, Buderus Wall-hung certification 2007, Power Limited License (low voltage controls) 40 CE credits 2005, Basic Hydronic Certification IPEX & Northern Alberta Institute of Technology 1998, Charter Board Member - Radiant Panel Association 1994, Residential Off-Electric to Hydronic Conversion Heating School Canadian Hydronics Council 1994, B&G Little Red School House 1993, Rood Utilities (now Auburn Technical Institute) Oil Burner School 1993 ,Tekmar Controls residential and commercial 1993, Division Manager and Advanced Hydronic Seminar Instructor for the first Exclusively Hydronic Radiant Floor Distributor in the USA 1990, Hydronic Radiant Heating Association Workshop participant with Richard c. Bourne, PE spring 1988, Master Plumbing, Hydronic, Solar Course Red Rocks Community College 1987.

Awards and Honors
2009 System Showcase Award - Radiant Panel Association

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