Tom,

The diverter in the shower and head need to be changed- they are about 15 years old- Moen or American standard- when my husband try to pull off the knob which control temperature and flow he must have distrub settings -now we only have very hot water- how do we remove the knob and back plate -the gold finsh is worn off.

There are 2 screws on the back plate.

Thanks

Post photo of the faucet...