Upside down manifold okay?

josephny

I'm installing my first between the joists radiant system into an old house with layers and layers of low quality repairs, modifications and additions (that is to say, it's slow going).

Usiing Uponor materials (pex, plates, EP manifold, etc.).

Can I install the manifold so that the pipes come out the top?

Also, I understand pex expands with heat, but I don't know how to allow for that expansion when the pex is in plates?

Thank you!

Ironman

Most manifolds can be mounted that way, but some caution that debris can get in the flow gauges causing them to be inaccurate.

The expansion of the pex in plates takes place at the U bends and turns at the ends.

ewang

Also consider that if mounted upside down, the included vents on the EP manifolds will be rendered useless.

By looping from above to come below, you naturally create a loop that the expansion can act upon and not cause issues.

josephny

Ironman said:

Most manifolds can be mounted that way, but some caution that debris can get in the flow gauges causing them to be inaccurate.

The expansion of the pex in plates takes place at the U bends and turns at the ends.

Thank you!

josephny

ewang said:

Also consider that if mounted upside down, the included vents on the EP manifolds will be rendered useless.

By looping from above to come below, you naturally create a loop that the expansion can act upon and not cause issues.

ewang said:

Also consider that if mounted upside down, the included vents on the EP manifolds will be rendered useless.

By looping from above to come below, you naturally create a loop that the expansion can act upon and not cause issues.

Sounds like you would advise to come from under and loop below.

Thank you!

Rich_49

Can you place then vertically ?

josephny

Rich_49 said:

Can you place then vertically ?

I don't understand (but would love to). Please what vertically?

Thanks!

hot_rod

If you use electric actuators on an upside down manifold, get the type that are sealed so any leak stays out of the motors.

Ironman

Placing them vertically means the manifold bodies are mounted vertically, instead of horizontally, and the tubing connections enter from the sides.

josephny

Ironman said:

Placing them vertically means the manifold bodies are mounted vertically, instead of horizontally, and the tubing connections enter from the sides.

Ah, got it. The pex all comes from on top (where the joists are), so it would be neater to have them come right down into the manifold, but ewang points out that come down behind and then under and in front of the manifold mounted on plywood would provide for expansion.

Thanks!

ewang

@josephny I just commissioned my new DIY system yesterday and despite the amount of real-estate needed to come from above and hit the bottom of the EP Manifold's, I am very glad I did. The vents that are included from Uponor's EP manifolds made bleeding a breeze.

josephny

ewang said:

@josephny I just commissioned my new DIY system yesterday and despite the amount of real-estate needed to come from above and hit the bottom of the EP Manifold's, I am very glad I did. The vents that are included from Uponor's EP manifolds made bleeding a breeze.

That's great! Congrats!

Would love to see pics.

Rich_49

here are some pictures of a system done quite awhile ago with both manifold orientations . https://mechanical-hub.com/langans/

josephny

That is some neat work! Thank you.

What do you call the brackets or hold downs that hold multiple pex lines against the back board?

Rich_49

That was done using Uponor 1/2" pex rails , cut to needed lengths . There is one attached to the board and another facing the board after all lines were installed then fastened . https://www.supplyhouse.com/Wirsbo-Uponor-A5700500-1-2-PEX-Rail-65-ft-2137000-p?utm_source=bingad&utm_medium=shopping&msclkid=4eccfefa3d651d3fd6dd9ef7893c4ab5

Darek_NYC

I did mine upside-down. It works for now. Look for my latest post. The went on the end of the manifold (if you have one) can be turn to upright position. I have only a purge valves on the ends and they also turns.