by Roxanne Prather

Troubleshooting a water heater

There is nothing worse than not having enough hot water or having no hot water at all! When this happens, you have a couple of choices: either you fix it yourself, or you call an electrician. It’s not that hard to fix if you know what you are doing.

First you need to know a little about water heaters and how they work. There are only a couple things on a water heater that can fail, your element or thermostat. 

Cold water comes into your water heater through the top and is pushed down through a dip tube where it gets heated before it moves up. The bottom element heats the water, and the top element maintains the heated water. So, if you jump in the shower and have no hot water, check the bottom element and bottom thermostat first. If you have some hot water or it is warm, but it runs out quickly and normally wouldn’t, then start at the top element and thermostat. 

If the water heater is old and you have a lot of sediment in your water, the sediment  can build up on the bottom of the water heater and cover the element, which would prevent it from working properly. You should notice this when trying to pull the bottom element. Sometimes it is so built up that you might have trouble getting the element out. If there is some sediment but it’s not too bad, you might be able to pull some out with a metal coat hanger after removing the element, but if it’s too bad then it’s time for a new water heater.

Before trouble shooting anything make sure you shut the breaker off so there is no power to the water heater. 

There are two access panels on the side of the water heater, one at the top and one at the bottom. Depending on what element or thermostat you want to check, remove that access panel and insulation and you will see a plastic cover covering the element and thermostat. Remove the cover but don’t touch any wires.  Use a volt strip (which is a little tool that will light up if there is any power) and touch the wire to verify there is no power. Then using a voltmeter on “ohms,” on the bottom element touch one probe to one screw and the other one to a good piece of metal on the inside of the water heater to ground it.  There should be no resistance; if there is any resistance the element is bad, and you need to replace it.

If you are checking the top element, with a probe you would touch the screw on one side and the screw on the other side with the other probe.  If the element is good, your ohmmeter should read between 10 and 16 ohms or somewhere close to that. If there is no reading, your element is bad and should be changed. If the elements are good check the thermostats the same way as the elements, sometimes all that is wrong is that the thermostat snapped off. This can happen if there is a surge in power, or it is sometimes caused by an element going out. You might be able to hit the reset button on the thermostat and be good to go. But if it happens again you need to troubleshoot to see what is causing the problem.

There are 2 types of elements, a screw-in and a bolt-on, you should be able to tell what you have by looking at the end, the screw in one looks like a big bolt and requires a special tool to get it off. The bolt on the other type has 4 bolts holding it on. Always replace the one you take out with the same amps, voltage and style as the one you took out. 

To change the bottom element, you should open the pressure relief valve for a minute then reclose it. Then go to the bottom of the water heater and put a container under the drain nozzle and open it for a few seconds and then shut it off. This will get rid of some of the water before you remove the element.  Pull the element straight out, being careful not to ruin the rubber seal. Make sure you have the new one ready to go in quickly to avoid more mess. 

If you are changing thermostats, make sure you have the same one as the one you took out. Pay close attention to where the wires come off on the old one so you can remember where they go on the new one. Some people take a picture before they take them off to refer back.

When you’re all done put the plastic shield back over the element and replace the insulation and the access cap. Then make sure the water heater is completely full of water before you turn the breaker back on. If the water heater isn’t full and any part of the element is out of the water, it will burn out when you turn the power back on.