Replacing a Heating Element in an Electric Water Heater
January 24, 2007
We receive emails and phone calls all of the time from people curious if they can replace their heating elements or do they need a new water heater. I am happy to tell you that you may replace the heating element(s) at a fraction of the cost to install a new water heater.
To get started you need to turn off the power to your water heater. Hopefully the circuit breaker is labeled. If you have a small water heater, 20 gallons or less (approximately 30 inches tall), it is probably a 120 volt unit on a single pole 20 amp circuit breaker and it will only have 1 heating element. If your water heater is 30 gallons or more (approximately 48 inches tall or taller), it is probably a 220 volt unit on a double pole circuit breaker (typically 30 amps) and it will have 2 heating elements. Once the circuit breaker has been turned off, go to the water heater and ensure the power is off using a volt-meter.
Now you need to turn off the cold water supply to your water heater and open the drain at the bottom of the water heater. To allow the water heater to drain faster, go turn on the hot water in a sink; this will allow air into the lines and tank. After the water has been emptied, check for voltage again across each terminal on the heating element to ground. If there is no voltage, remove the wires.
After the wires have been removed, remove the heating element. It either bolts in or screws into the water heater. If it screws in, you will notice a large hex type nut that is part of the element; you can get a water heater element socket to remove this at most any hardware store. With your element removed, take it to Home Depot, Lowes, a hardware store or a plumbing supply house and get 1 or 2 new ones. If your tank has 2 elements, I recommend changing both of them. Even though only one of the elements is bad now, the other one will probably go bad shortly. Water heater elements are relatively cheap, approximately $15.00 – $25.00.
Before installing your new elements, I recommend cleaning out the sludge in the bottom of your water heater. The easiest way I have found to do this is with the back of 500 series wiremold. You will also find this wiremold at Home Depot, Lowes, a hardware store or an electrical supply house. The back slides out of the wiremold cover and is approximately 1/2 inch wide. Bend the end approximately 4 inches back at a right angle to form an “L” shape. Insert this through the bottom heating element hole and pull the sludge out. This sludge is typically the cause of your heating element going bad. This is slow and tedious work, but it needs to be done to ensure the longevity of your heating element.
Be sure to clean the entire area around each element opening and replace all seals or gaskets. If your element threads in, be sure to wrap some teflon tape (clockwise) around the threads to prevent leaks. Now hook up the wires to your heating elements.
Make sure you close the drain at the bottom of the water heater and turn on the cold water supply. DO NOT turn on the circuit breaker until the water heater is completely full, as this will instantly ruin your new elements.
Once your water heater starts to get full, the hot water that you opened to drain your tank will start flushing out the air. Leave this open until the air stops and just water flows out of the faucet.
Congratulations, you just replaced your electric water heater elements.
Do you need assistance with your electrical wiring project? Please visit my DIY Electrical Wiring Help from a Master Electrician page. Where I provide electrical wiring tips, expert electrical advice, answers to your electrical questions and electrical consulting & design services over the phone, via instant messenger or via email.
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