I have one doing the same thing and prolly because it's leaking. Lower pressure means when the valve shut that station off, the leak cause it to lose vacuum and not go back down. You can simply push them down with your hand--WD40 might help that.
We just bought a 3 yr. old house w/Irritrol controller/heads...saw yesterday that some of the rotaters were replaced w/Hunter PGJ. Anyway one of the old ones is leaking at the base and I'd like to use the PGJ's. Water bubbles were coming up at the base. How do I replace these heads and also the stationary (small) heads?? Great forum, glad I found it.
