I have a 1930's house. This shower was added a little bit later. All of the plumbing involved here is galvanized and at least 50 years old. Here is the shower - hot water full open:
The cold water in the shower, Toilet and Sink (both hot and cold) work fine and have good flow. But the hot water in the shower is severely restricted.
It has separate hot and cold valves and I have taken the valve apart to clean it out (nothing much to clean out). I turned on the water to the house while the valve was apart hoping to flush anything out of the like (the pressure coming out of the hole was not very much).
Am I correct in assuming that the problem is rust in the hot water line?
And the only way to fix it is to replace the pipe?
Most of the rest of the house is already copper and while doing another project downstairs I ran new copper hot and cold lines to just behind the shower (these are capped and have nothing to do with the current system).
The problem with switching to the copper lines is this shower is in a dormer and although it's possible to crawl behind the shower through the attic space you can only get to the bottom 2' or so. Since the sink right next to it has good hot water flow I'm assuming the blockage is likely to be in the shower wall and the only way to get to is is to rip out that wall. That might be the thing to do if time and money were not objects but sadly they are.
Thanks for any thoughts.