I started getting only warn, not hot water in my shower (all other taps are fine) I tried playing with and removing the anti-scalding device with no luck. My guess's maybe the shower valve is bad.
I don't own the place and with everything that is going on, it's not an ideal time to call a plumber.
The only solution I found at the moment is slightly close the cold water ball valve behind the shower. However, I'm not sure if that will cause any other issues or will wear it out while we wait to get it fixed.
Best Answer
Using the cold water shutoff valve to reduce the flow of cold will not cause any other issues or wear it out. You most likely have a sediment blockage in the hot water shutoff valve or in the shower valve.
Since you do not own the place, it is most likely the owner responsibility to have the shutoff valve repaired or the cartridge in the shower valve repaired.