Can I use a multimeter to see if an immersion heater has failed?
When they fail immersion heaters will often crack, with the heater installed, all of the wiring disconnected and using resistance scale test from connection point to ground, if you get any reading other than open the heater has failed. Then do a second test across connection points, if open the heater has failed. If it passes both those tests, check your thermostat the upper stat will have an overheat reset button, remove the wires and test across it to find full scale on the meter if not push the button and read again, if still open then it has failed. Next test the upper stat it will have three connection points, one in 2 out put the meter on the in and out to upper element, should read full scale, if not turn the dial up to the top, if still open then it has failed, finally test the bottom stat it will have two contacts test then the same as you did the top stat. Connect the wires back on after each test so you don’t forget how they were connected.
