Is the element the problem?
We will begin by testing the element to see if it is bad. To begin, shut off the breaker for the water heater. Next, you can remove the access cover(s) and pull back the insulation. Verify that there is no power to the unit with a multimeter.
Now, you can disconnect the electrical wires from the element(s). Using a multimeter, check the resistance between the two terminals on the element. The typical resistance should be between 10 and 20 ohms. If your reading is zero, then the element is shorted and must be replaced. If the reading is much higher than twenty, the element is open and requires replacement.
Next, you should check the resistance between the terminals and the tank itself. The reading should be very high or the element is grounded and requires replacement.