Pex AL Pex & no plates for staple up ?

Andrew Hagen_2

The aluminum does nothing for the heat transfer. The aluminum helps by greatly reducing the thermal expansion of the pex. Plates are very important to reducing the required fluid temperatures for the system. When it comes to conduction, it's all about contact area.

Rod Kotiga

Has anyone tried using a Pex Al Pex tubing without plates with any success. We all know the Watts people say they have done case studies and have found that you don't need plates. ( There opinion ) Well if they don't use plates because there Onix has an Al barrier which also helps in the transfer of heat then does that mean if you were so inclined you could use Pex Al Pex with the same results at a third of the cost of Onix. I mean if the areas in question will heat with Onix and no plates then why not Pex Al Pex ?

Rod

Unknown

This is from,

the Ipex manual.

Dave

Unknown

And this,

was Siggy`s article.
You be the judge.

Dave

Rod Kotiga

Andrew your right about the Al in the pex or Onix. It has no performance benefit and Watts said the same. I was just wondering if anyone has had any luck using Pex Al Pex without plates. Iv'e read Siggy's article more than once and plates are the way to go for sure I just have a stuburn Contractor.

Rod

Jim Erhardt_3

A bear...

Never tried PAP in a staple-up application, but I suspect it would be a real PIA to work with. Pex with extruded plates or Onix would be my primary staple-up choices.

Unknown

as Dan would say it all depends....

not to be a smart a$$ but it all depends on the performance you want and need. I have designed and supplied jobs with PAP without plates... but why spend the extra bucks when PEX is easier to work with (I sell both).

If you BTUH demand is high you will need plates to reduce water temp and decrease reactionary time. If your demand is low the no plate rule may apply.

Of course if you are going for MAX efficiency then use plates.

See, it all depends!

skw

hot_rod

pex or PAP with UltraFin

would be another option. Better performance than bare tube staple up, but not a conductive transfer like extruded plates.

It all depends on the loads (btu/sq.ft.)

hr

[Deleted User]

well, there's the next 'product'

attach al strips to the sub floor before it's put down. then staple up

EMB

PAP staple up

Okay, I asked once before how one uses PAP in staple up without a bazillion couplings or kinks but no one seemed to have a cost effective solution, or indeed any solution. The minimal expansion has definite merit, but can it be done cost effectively? Just curious.

Enda

lee_7

We ran close to 1500 feet of Kitec pap with plates, with no couplings, with the exception of the couplings we planned for. Had to put couplings in loops when changing from addition basement to old basement. 2" holes and just keep making loops, then pull down joist bays. it works, takes a little extra time, but it works.

Rod Kotiga

Very carfully is how you do it. It's not as kinky as you think. With two guys it goes preety smooth. Also I was thinking about 3/8" Watts PAP to make things even easier. For some strange reason Wirsbo MLC Pex Al Pex is cheaper than their He-pex ?? I would think it would cost a ton to sandwich in aluminium in there ??

Rod

hot_rod

PAP

does take some extra care when pulling thru holes and open web trusses. But it is do-able. A good uncoiler, two installers, makes the difference. Yes, it does take some patience and practice.

Kitec use to have an installation video showing a good method, called sewing, or something like that.

A better tubing option is the Viega FostaPex. It's a full size pex tube with the aluminum wrapped around the outside. It doesn't kink like PAP and has a very durable outer PE layer. So you get the best of both, a full size pex tube with two extra outer layers and the aluminum.

It does require a stripper tool to remove the outer covering for the crimp rings.

hr

Rod Kotiga

Are ther any noise issues with PAP stapled to the sub floor, like expansion ?

Rod

John_162

Viega FostaPex

hr,
you can't use crimp with FostaPex. you need to use Viega Press fittings with Press Sleeve's. if you try and use crimp fittings with crimp rings it may leak and Viega won't cover it because its not approved fitting system with the tubing

Steve M_2

no noise

Haven't had any problems with noise with PAP because all the systems I've done have been continuous flow, either via injection pumping or with TRV's. I think PAP is easier than PEX in doing staple up because it keeps its form and doesn't coil up when pulling thru the joists. By all means, use plates. Show your contractor the link that Dave put up eariler.

hot_rod

yes, use the factory approved

fitting and connection.

I have used off the shelf pex manifolds and crimp rings for test manifolds with FostaPex, removed them after the pour and building construction to installed the finished product with the Viega connection.

I have a bundle of test manifolds from PHP that I used over and over for the test and pour part of the job. Concrete finishers can be fairly rough on radiant manifolds.

hr