Please find and identify the tank serial number on the template of your tank. The serial number is the date in which your tank was made. Please check the date of manufacture. If you tank was purchased prior to the 2/4/2013 Please contact Hills email@example.com or call (8) 81869267. If your tanks date of manufacture was after the 2/4/2013 then you must fill out the below details to lodge a warranty on your tank.