Are there any reasons one would not use aluminum or flexplates with Onix tubing? It seemsw these are a better system to transfer heat and increase transfer with PEX so why not use them with Onix? It is also easier to install than the insulation.
Post by Watts Radiant on Apr 14, 2011 7:50:02 GMT -6
The short answer is that since using Onix+staples creates a tight surface in a staple-up application, the heat transfer plates aren't really necessary.
The typical (historical) application for PEX was a suspended system, doing so dramatically decreased the amount of total heat transfer to the floor. The transfer plates allow the PEX to utilize conduction and keeps the PEX in place during thermal expansion. Staples with PEX is also sometimes seen, but this is a terrible application and we don't even talk about it.
We have not designed nor installed an Onix+plates application at this point as the plates are designed and tested for PEX. You could theoretically use Onix with transfer plates, but due to the difference in outer diameter sizes, cramming the Onix into the plates would most likely either distort the plates or the Onix (or both). This is not an approved application however, and we would not be able to guaranty the integrity of the components.
You'd be better off beefing up insulation underneath and around the perimeter than spending the extra money on plates.