****PLEASE MAIL COPY OF INVOICE**** Performed diagnostic on 2 1/2 year old water heater Checked for incoming power (adequate) 240 volts AC Checked upper and lower elements both good Water temp was set at 140 degrees (extremely hot) Temp increased by others (Not CPI) Lowered temp on upper and lower thermostat Temp is at approximately 120 degrees Shrader valve on expansion tank not releasing air, indicates expansion tank has failed and not working properly Performed drain and flush of water heater removed sediment And refilled tank Tank is still making loud rumbling sound Tested house water pressure guage read 120 psi this is 40 lbs above safe working pressure STRONGLY RECOMMEND pressure reducing valve and full house emergency shutoff valve in an accessible location In home Left option Confirmed noise was from temperature and pressure relief valve on water heater opening, and discharging hot water to emergency drain piping (copper down the front of tank) felt heat through pipe after