Lost water pressure - Shower

Hey guys, seeking some advice here.

My showerhead seems to have lost pressure after some service from my building maintenance. They haven't been able to diagnose yet so coming here for advice because I feel the issue should be simple, but I'm no plumber.

This is the set I have: [www.amazon.com]

Moen Chrome Single Function Eco-Performance Shower Trim, (Posi-Temp Valve Required), [a.co]

The issue began with my shower handle requiring a lot of force to turn it off only. Turning it on was normal. After a few days of that, the handle broke while showering so I was neither able to turn the water off or change the temp, it would just spin and the water running where it broke.

I reached out to maintenance for them to change the handle, and they did. As well as my showerhead which I asked them to swap as well. Ever since they did this, my showerhead water pressure is much weaker, but the tub faucet seems the same, or I can't tell a noticeable difference. They replaced it with the same model Showerhead.

More details: when they were here, I mentioned to them that when I turn the shower on there's not much of a cold water setting, it kind of just starts at room temp and gets hotter. They said they will adjust the dial. The handle is now a lot looser than even before and I have to turn further to get hotter water. Also, the water dial turned on just a bit is hot/warm, got to turn a bit more for cold. In hindsight , should've stayed quiet.

When I turn on the water and use the tub faucet, it now makes a loud humming, vibrating, sound that seems to come from the pipes. This did not happen before. It stops when I turn on the showerhead. Though the water doesn't sound the same coming out, could be because of the pressure though.

The pressure in the tub faucet seems to be unaffected. The pressure in all sinks everywhere else in my apartment is also unaffected.

I checked my main water valve, and it is all the way open.

Thoughts?



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Did they remove and check the cartridge when the handle was replaced? Has the new showerhead been removed and checked for debris?

yeah, they need to turn the water off, remove the cartridge and turn the water on with no cartridge in there. flush out the valve body for for just a few seconds and turn the watwer off and rerplace the cartridge. in fact, while they have the water off and the cartridge removed, might as well replace the cartridge.
now remove the shower head and run the water to see how much water comes out of the shower arm and how the temperature control is acting.
there is probably some kind flow restrictor in the shower head but if you remove it you may be called before a senate committee.

We changed the cartridge and flushed but it had no effect, the humming/vibrating sound still persists when using the tub faucet, and now the showerhea too. I did remove the flow restrictor which gave me most of my lost pressure back, but not all.



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