In the master bathroom shower unit I have one handle for both hot and cold water. When I turn the valve full hot I get very little pressure, but when I turn full cold I have great pressure. The other hot water lines in the other shower and fauctes are fine. I have a feeling I have a small build up restricting the flow in the hot supply line for this shower. Is there a way to clean this out either by non-hazardous chemical or air pressure blow out, or do I need to remove the supply line and replace it? Thanks