Repair or replace damaged PEX in a quik trak under floor radiant system

dwa

I am installing radiant heating under a kitchen floor in a new residential house using quick trak in the kitchen.

I realised there was damage to the pex pipe just before laying the plywood layer, do you recommend removing the entire pex loop and starting the loop installation again to ensure a continuous loop of pex or is it safe to cut the short damaged section of pex out and repair the short section (couple of inches) ?

I am new to radiant heating but confident in my pex crimping abilities . When complete there will be a heat reflector, plywood and ceramic tile above the pex. Is the crimp joint likely to deteriorate over time due to it being under a floor ?

Should I repair and save time and money now or is it likely to cost me more in the long run several years later ?

Any guidance woudl be much appreciated.

Thanks.

Rich_49

dwa,
While you may be confident in your pex crimping abilities I strongly suggest you not crimp Uponor PexA tubing . The only fitting I am aware of that is acceprable for warranty and QC purposes is Uponor A4010313 repair coupling for their 5/16" tubing . Are you certified by Uponor to install their product ? I would also suggest not using layers of other material over top of QuikTrak as you will derate the BTU output and quite possibly end up with as disaster for which there will be no one to point at other than yourself . Replace the plywood with Hardi backer maybe but not plywood , then you can do thinset on top of that . Do your research and do it right . If you'd like suggestions many here can assist .
I suggest Sunboards' foam panel with 1/2 pex . this has superior output to all other competing products and will lessen the head and thus the required pump .

kcopp

If its Quik trac you cant crimp it. There is not a crimp fitting. Its 5/16" tubing. If it just one cut you can get the fittings and cut a space in the floor for it to fit.

Bob Bona_4

Most likely you're going to either need to router the nearest return panel to redirect the tubing so you have some slack to submerge the QS repair coupling, or you're going to need 2 of the couplings and a section of tubing to get that slack. You will need to create a smooth gentle gradient groove in the area on both sides of the repair, and create a slot in the floor about 1 1/4 wide x about 4-5" long to accept the coupling so it's all below the panels when done. It's critical that no stress or chafing happens where the tubing dips down to the coupling or stress from too short tubing ends acting to pull the connection apart. Then pressurize.

Paul Pollets

Viega makes a 5/16" crimp coupling which is far more reliable than the mechanical compression coupling. I would still be very hesitant to install couplings that require the floor to be removed if it fails.

hot_rod

Properly installed the crimp fitting should last as long as the rest of the system. A couple of these and a short section of tube would be one method.

dwa

Thanks everyone, sorry Rich, i added some confusion into the discussion, I called it quik trac since that is what I originally intended to install as I learned about that product first but ended up installing watts radiant sub ray. I keep incorrectly calling it quik trak, my bad. The sub ray uses an aluminium conduction layer above the pex. It's the pex that has the damage. I am the home owner working with a general contractor for some aspects of the build and taking on some tasks myself. The damaged pex is about 10 feet from the manifold. I will look at some of the fittings suggested here (thanks) and instead of cutting out a few inches of pex and using 2 joints I will remove one side of the damaged pex back to the manifold so there is only one coupling instead of two. The area above the ceramic is in the middle of the floor with no plans for cabinets over it, will make sure i accurately record the location of the joint for future reference