Customer had 13 yr old heater stop heating. Also found a couple incorrect installments of items relative to heater. Checked pressure, found pressure to be at 165PSI. Customer also mentioned slow draining shower. After reviewing issues at hand, gave a few options for repairs/replacements. Replaced heater with 50 gal Rheem water heater. Also installed new PRV with main valve. Later ran small machine into drain line for shower. After machine filled shower stall and allowed to drain to check for proper drainage. Checked for leaks and proper function. Pressure is now set at 60PSI.