Testing heating elements with an ohmmeter is the best method.
Electric water heating elements are in direct contact with the water. Over time, minerals and other impurities in the water will corrode the metal elements. A lack of hot water is a good indication of a bad heating element. Most electric water heaters use two separately controlled electrical elements. One heating element is located near the top of the water tank and the other is near the bottom. Each element is controlled by its own thermostat. The best way to test and troubleshoot the element is by using an ohmmeter. Does this Spark an idea?
Instructions
1. Shut off the electrical power to the water heater. This may entail switching off the circuit breaker or pulling the fuses that supply power.
2. Remove the metal cover that conceals the electrical heating element at the top of the water heater tank. Most models use two screws to secure the cover to the water heater housing. Pull the insulation from in front of the thermostat and the heating element. Slip the plastic insulating cover off to reveal the heating element's electrical screw terminals.
3. Disconnect both electrical wires from the heating element screw terminals using the screwdriver. In most cases, a single black and single yellow wire is connected to each of the screw terminals on the element.
4. Insert the red lead into the front connector on the ohmmeter marked "Ohms." Slip the black lead into the "Com" connector on the ohmmeter. Switch the front dial on the ohmmeter's face to "X1 ohms." Touch the metal ends of the leads together. The meter display should read "0 ohms."
5. Touch the metal end of the red lead to one of the screw terminals on the element. Contact the metal end of the black lead to the other screw terminal on the element. A good heating element should read approximately 15.5 ohms for a 3500-watt element, 13.0 ohms for a 4500-watt element and 10.0 ohms for a 5500-watt element. A broken or burned heating element will read "Inf," or infinite ohms, on the meter. If the meter reads 0 ohms, the heating element has a direct short and is also bad.
6. Test the second element on the water heater following the same process.
Tags: heating element, screw terminals, heating element, water heater, black lead