Running out of hot water before you finish your morning shower is one of life’s little irritants. If you have an electric water heater, the answer may be as simple as adjusting a thermostat or replacing a heating element.
Your first task is to check the settings on the thermostats, of which there are two on most water heaters. First, check your electrical panel and locate and shut the circuit breaker that controls the water heater – you’re dealing with 240 volts as soon as you open up the water heater, so DON’T TRY AND DO THIS WITH THE POWER ON. There is, however, no need to shut off the water for this first step.
Remove the two access panel covers on the front of the water heater, which are held in place by one or two screws each. Set the panel covers and screws aside and, if present, remove the small insulation blankets inside the access areas. This will expose the thermostats, which are simply two small dials marked in degrees Fahrenheit, with a small adjustable pointer.
First, check to see what number the pointers indicate, and that both pointers are set the same. For the typical residential water heater supplying hot water for bathing, laundry and a dishwasher, the thermostats should be set between 130 and 150 degrees, depending on how much hot water you use and what your personal preferences are. At settings much below 130, you’ll have a hard time maintaining a large flow of hot water, and this may be below the minimum temperature recommended by your dishwasher manufacturer. On the other hand, settings above 150 will waste electricity and increase the risk of scalding, especially for small children.
To set the thermostats, simply use a screwdriver to move the pointers until they point directly at the desired temperature. Be sure that both thermostats are set to the same temperature.
To change a water heater element, you first need to drain the water out of the tank. After shutting the power, close the water inlet valve, which is typically located above the water heater on the cold water side (the lines are marked with C and H where they enter the tank). Connect a garden hose to the drain valve on the bottom of the water heater, and route the hose to a convenient location before opening the valve. To help the flow of water coming out of the hose, open a hot water faucet near the water heater, or loosen one of the flexible water lines where it enters the water heater.
When the tank is drained, close the drain valve and remove the access panel covers as described above. Near each thermostat, you will see a fitting that resembles a large bolt head with wires attached to it. Make a note of how the wires are attached, then disconnect them. Using a special water heater element wrench, which looks somewhat like a socket wrench, unscrew the fitting and remove the element. Element wrenches are available wherever the elements are sold.
Water heater elements are rated by their wattage, and are sized to specific tanks. Your best bet is to take the old element to a home center or plumbing supply retailer and have them match you up with a new one. For best results and longest life, it’s best to replace both elements at the same time.
To replace the elements, simply reverse the above procedure. Be sure that any gaskets or washers are in place, then screw the element into the tank and tighten it securely. Reconnect the wires in the same configuration as before, then replace the access covers. Make sure the drain valve is shut and that you’ve retightened any pipes you loosened, then open the inlet valve to refill the tank. Leave a hot water faucet open near the water heater to allow air to purge out of the tank as it fills. Once the tank is full and water is coming out of the faucet, turn the power back on. NEVER turn the power on when the tank is empty or only partially full – that’s a sure way to burn out the elements.
Remember, if you’re uncomfortable with any of the plumbing or electrical connections, contact a qualified, licensed plumber or electrician.
Remodeling and repair questions? E-mail Paul at firstname.lastname@example.org.