Replaced two 2” Watts PRVs. Replaced one 2” union that was leaking. Replaced the 4.5 gallon expansion tank at the water heater. Installed hammer arresters on the hot and cold water lines in the ceiling of the first floor. We adjusted the water pressure to 50 PSI and inflated the expansion tank. We bled air from all of the fixtures before turning the water heater and recirculation pump back on. The hammering and vibration issue have been resolved. Thank you for choosing TE Certified!