Maybe get a brass threaded coupling to screw onto the threads to protect the thread.
I think that a NPT or NPSM thread should work.
Get a 1" pvc threaded fitting to try on for size and then get the brass fitting once you know the size.
Don't damage the threads.
Just screw it on until snug, but not tight.
Below says that it is a 1" fitting with 11.5 threads per inch, which is standard NPT.
Hi Everyone, I have a Hayward model S244T sand filter with a drain at the bottom. Can anyone tell me what size and what the thread type is on that drain cap/outlet? I would like to connect a hose to it for when I drain it at the end of the season. Thanks
www.troublefreepool.com
NPT – American National Standard Pipe Tapered thread.
This type creates a pressure-tight seal, which occurs when the male and female NPT threads compress and tighten.
NPSM – American National Standard Pipe Straight Mechanical Joint thread.
This type creates a non-pressure tight connection in applications that are not subject to internal pressures.
Both NPT and NPSM connectors have the same number of threads per inch, and the angle of each thread is 60 degrees.
The obvious difference between NPT and NPSM, as their names indicate, is that the former is tapered (slightly conical) while the latter is straight (parallel).
Maybe something like this?
SharkBite 1-in PEX x 1-in NPSM Brass Female Swivel Adapter
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If you use just the brass threaded part, that should protect the threads.
Wrap up a radiant water heating system to your residence with the addition of this affordable Apollo Brass PEX Barb NPSM Swivel Manifold Inlet Adapter.
www.homedepot.com
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