Roof wash-off shingles granules and multi-port gasket

[Desmond.TFP]

My composition shingle roof sheds granules (not abnormally so). The pool edge is about 15 feet of Sundek away from roof line, so some granules end up in the pool & some of those end up (probably during backwash) in the multi-port valve and embed under or in the gasket, causes some gasket malfunction.

Any suggestions on how to minimize this problem?

Thanks!

 

[ajw22]

It is helpful us to know you location by putting it in your profile so it shows up
<<----here