It functions normally, but now it's making a squealing noise when it opens.

I checked the diaphragm and it looks fine to me:


I think the black stuff on the diaphragm is tarnish from the aluminum slidey-part. I could not hear it previously; do you EWG guys hear your WG's open with the dump plumbed back into the pipe?

Thoughts?

 

Never heard a squeal on mine but I have the old style gate.

Call Tial? They answer the phone and support is helpful

 

Best solution is to not run an external gate.

 

That would just make your job of building downpipes even easier then.