I have a Delta shower with a single handle. It is a shower only and about 10 years old. Just recently I tried putting on another shower head and it did not work so I put the old one back on. The new one did not work in that no water came out.

After that is when I tried turning on the water. When I turned it to the hot water side the pressure was very low and not much hot water would come out. On the cold water side it was fine. I tried removing the shower head and looking for anything that might be slowing or stoping the water but could not find anything.

I also tried another shower head thinking that I might have done something with the old one but still the hot water pressure was low.

I tried checking the rest of the house and the hot water pressure seems to be fine. There is a tub in the same bathroom and it works fine.

I read about sometimes there is a pressure value in some showers but I think this one is too old for that.

If you have any suggestions I'd appreciate it. Thanks.

So from what you say everytnig was fine until you trieda new shower head> then the problems started and the brand new head did not work, very strange but is it possible your supply pipe coming out of the wall has a small slide shut off? Try removing everything from the pipe in the wall so all that is left is the chrome curved pipe, how is the pressure?

It is likely that it is not in the riser or shower head if the cold works fine. Simply replace the cartridge and flush out the valve body when the cartridge is removed.