Replaced homeowners Pressure reducing valve due to high water pressure and thermal expansion tank. Installed watts PRV and set pressure to 60 psi. Located the pinhole failure on the 1/2 hot side uponor piping in the half bath on the main floor. Removed manifold and installed new section of pex piping. Replaced the master and upstairs kids bathroom shower cartridge. Turned water on and tested and everything is working properly at this time.