Shower "screams"

Jazan

My shower, after a few minutes of use, starts a high, shrill scream sound.
This noise continues for the rest of the time the shower is in use.
We use a Moen Positemp rotary style control. We've had this for at least seven years, but this problem just started this year. Any suggestions
would be greatly appreciated.

Alan

Perhaps the cartridge could use some greasing. More than likely the balancing spool inside is causing that sound.

__________________
Journeyman Plumber

joecaption

Got another shower in the house? IF so switch the shower heads and see what happen.
I'm thinking pluged up head. A real simple thing to check before messing with the balancer.

Jazan

Alan and Joe, Thanks for the suggestions. I think I'll try the easiest idea
first, removing the showerhead, then replacing it with the identical head
from my second shower. If the sound isn't heard, I'll clean the old head
in case it's clogged. If the sound remains, I'll lube the cartridge, or maybe change the cartridge while I have the chance. Thank you both!

Jazan

After paying close attention to the noise, I found that it was coming
from the diverter, not the shower-head or the cartridge.

I switched the diverter from another shower in the house and it did not scream in use. When I put the screamer on the other shower, it did.
Solution: buy a new diverter and the problem is gone. Thank you, everyone who had a suggestion for me to try.

By the way, I also learned something in the process. I did not know there
are two types of diverters, the screw-on type and the o-ring press-on type. Mine happened to be the latter. Most stores don't seem to carry that kind, but Home Depot does. The package even comes with an allan wrench, but does not come with any silicon "grease". It should, though.