Fitting Thread sizes

kennethruiz

I have an Uponor EP heating manifold. The loop male thread connections are listed as R20.

I want to make sure, before ordering, that Caleffi Fitting 5/16" PEX Loop Fitting for Manifolds is compatible.

The supplier was unable to confirm. These are half the price of Uponor's and I need 10.

Thanks in advance for any help.

Jamie Hall

It is my understanding that R thread is the same as — or very similar to — British Parallel Pipe Thread — BPPT. It is NOT interchangeable with NPT. Not sure what thread the Caleffi manifold uses ( @hot_rod ?)

kennethruiz

Thank you, from the research and information I could find, I believe you are correct.

The only information on the Caleffi thread is : 3/4". no other information is provided.

Thanks again.

hot_rod

the R20 thread is a standard, straight thread, but the shape of the tailpiece and o ring can vary from brand to brand, where it seals into the manifold

The Caleffi has both a taper and o ring, so it is fairly universal

Also, the part that goes into the pex has a slight taper and an o ring for pex that may have a large id