To repair an electric water heater, you must first identify the specific problem. Generally, electric water heater problems include inability to heat water, overheating water and water leakage.
When a heater fails to heat water, it may imply that the electric power does not access the heating elements or that the electric thermostat is faulty. It may also indicate that the upper electric heating element is defective. To fix these problem, disconnect the heater from the power, and reset a tripped circuit breaker or replace a blown fuse so the power reaches the water heating element thermostat. If necessary, replace a faulty thermostat and upper heating element.
To fix a heater that produces excessively hot water, check if the setting of the heating unit thermostat is abnormally high, and adjust the upper and lower heating element thermostats to between 110 and 140 degrees Fahrenheit, which is the normal range.
To repair a leaking water heater, check a leaking tank for corrosion, and replace it with a new tank. Repair a leaking temperature and pressure valve by opening and flushing the valve to remove dirt. Replace the valve if it still leaks after flushing. If the leakage is from a pipe connection, tighten and snug the connection with a wrench.