① found signs of failure, should disconnect the power cord connector and unscrew the electric water heater socket, with a zero emery cloth or grinding paste polished to light, remove the power cord and electrical connector contact tongue at the junction of the wire , Wiring screws, tongue and electric water heater socket conductive column oxide layer to reduce the contact resistance.
② Apply a little conductive paste on the socket lead post of the power cable connector and water heater.
③ tongue on the electrical connector, screw serious burning wire to replace immediately.
④ electric water heaters on the socket and conductive column serious burns also have immediate removal, replacement of the same size socket and conductive column. In the installation of electric water heater socket, should install a power knife switch.