I just changed the hot water stem & knob . Replaced with the same parts . Water pressure was not great before I had to do the change but was all right, very good from cold water side.HELP PLEASE!

You may have dislodged some mineral built up in the pipe walls that's now clogging the hot water seat. Shut the hot water off and remove the stem and washer assembly. Now turn the water back on to flush out the hot water supply. Pressure better now? Regards. Tom