Troubleshooting and Repairing Electric Water Heaters
Electric Water Heater Troubleshooting: The Basics
- When I say “water heater," I am referring to a 30-gallon electric water heater, but the same principles described below will apply to a 60 or 90-gallon water heater.
- The unit is powered with 240 volts and contains two heating elements and two thermostats.
- Of the two heating elements, only one is used at a time. One is located at the bottom and the other at the top, and when the bottom reaches the set temperature, the heating element shuts off and the top one kicks on. This cycle repeats.
- If you are getting hot water for only a couple of minutes, then you may need to adjust the temperature on the thermostats. However, make sure that you secure the power to the water heater before you take off the access panels to the thermostats.
I will be going over some basic troubleshooting for broken electric water heaters here: not gas, not tankless, but electric. If you need information on the other types, I am sure you can find an article elsewhere, but as for now, I am going to cover everything that you need to know about electric water heaters.
How to Replace a Water Heater Hose
Before you go and try to replace a water heater hose, you better have some general plumbing knowledge. If you do not follow the correct steps, you could flood your house in a matter of minutes.
- So the first thing that you need to do before you start loosening connections is to turn off the water that is going into the water heater.
- After you turn it off, run a test by turning on a few faucets on the hot water side only to make sure there is no water coming out of them.
- Now you can begin replacing the part. Begin by removing the leaky hose. Some hoses can be disconnected with a pair of pliers or a wrench, just make sure that you have the right type of hose connections to make this work. Sometimes the hoses are connected by solder: If so, you will have to cut the pipe and detach the hose. If you have soldered fittings, the new hose can be connected by using either a compression fitting or soldering the new hose back on. If you have no experience soldering copper piping, don’t try it, leave it to the pros.
- Once you have your hose connected, you can reopen the inlet water valve (hot side) to the heater, just make sure that you have a faucet valve that is open somewhere in the house to relieve some of the pressure.
Resetting the Reset Button
Checking the Heating Elements and Thermostat
Although there are a lot of articles on the web that explain how you can check the heating elements, I have only read one or two that tell you how to do it correctly: the others are all crap.
- Before you start undoing access panels and all of that, check the breaker box and make sure there isn’t a tripped breaker. If the breaker is good, let’s move to the next step.
- You'll need to have a multimeter in hand, and it has to be able to check ohms or continuity.
- Make sure that there is sufficient power going into the water heater; you should have two wires going into the unit that have 120 volts each. If you are not getting a full 240 volts, then there is a problem with the breaker, and it may need to be replaced. (I will not be going over this in this article, it’s a whole other can of worms). If you are not experienced in working with electrical, do not even bother, it’s too dangerous, get a professional or somebody with experience to help you. Okay, if you've got 240 volts to the water heater, we are good there, so let’s get to testing the heating elements and thermostat.
- Take off the access panels, which are usually secured by a couple of hex-headed screws. Look for the thermostat first and remove any insulation that may be blocking it. Look for a little red button: if it is off, that means that the thermostat is tripped. Pushing the button back in will fix this problem in most cases, but if it just pops back out when you turn the power back on, then the thermostat needs to be replaced.
- Now to test the thermostat and the water heater element, you need to turn the power off!
- Remove one of the wires from the thermostat. You can remove all of them if you want, but it is only necessary to remove one. Set your multimeter to ohms, then take one of the probes on your meter and stick it on the first screw, the one without the wire connected. Holding that there, with the other probe go and test each screw and each connection.
- If your meter is reading .1, that means that the circuit is open: this is good, this means that your thermostat or element is good. If your meter is reading something like .003, it will eventually drop to 0, which means that the circuit is closed, which means that you will have to replace the thermostat or the element. Below is a picture of me testing a thermostat.
- If the thermostat is bad, just replace it. You already have the power off, so just hook up the new one exactly how the old one was hooked up and set the temperature accordingly. If the heating element is bad, then replacing that is a bit different, I will explain how to do this below.
Replacing a Water Heater Element
So you should have already tested the element as I said to do in the paragraph above. Once you confirm that the element is bad, let’s get to work.
- Shut off the power to the water heater and turn off its water.
- Lots of people recommend draining the water heater before changing out the element, and this can be done by hooking a garden hose up to the drain valve and siphoning the end of the hose to create a vacuum. Then you wait 30 minutes to an hour for it to drain. You might also check to make sure it is drained completely by opening up some hot water valves throughout the house. You can do all this, or you can listen to me and save yourself an hour and skip the draining: Just grab a few towels and lay them around the water heater. When you are pulling the element out, some water will come out, but it is not pressurized, so if you swap the elements out quickly, you will barely get any water on the floor or carpet (that’s what the towels are for, more than enough to soak up the little bit of water that will come out).
- Unhook the couple of wires on the old element. You will need the appropriate size lug wrench to loosen the element. Have the new heating element on hand: these elements come with a rubber o-ring on them so you will not need to use any Teflon tape.
- Unscrew the old element and pull it out (if you didn't drain, some water is going to be pouring out so make the swap quick), then tighten down on the new element. Hook up the wires as they were before. Put back any insulation you may have removed and put the access panel back into place.
- Turn the breaker on to the water heater and turn on the water and you are done.
Tank Element Replacement
How Do I Know When I Need to Replace My Water Heater?
Is your water heater leaking?
The first sign of your water heater going bad is when it starts to leak water, usually from the bottom of the unit. The leak usually starts as a pinhole and gets worse over time. This is just normal wear and tear, a common problem for water heaters that are anywhere from 10 to 15 years old.
The easiest way to tell if your water heater is leaking is that you will probably start to see some rust marks or water stains coming down from the unit.
Now it may be that you simply have a leaky hose. If so, then you will just need to replace the hose itself.
Is your water heater not heating?
If the unit is acting up and not heating right, then there is either a problem with one of the breakers, one of the heating elements, or one of the thermometers that are behind the unit's panel. Those are the main parts that are inside, and it is common that they fail every once in a while. You'll find solutions below.
Where and what kind of water heater should I buy?
If you do need to replace the unit, there are many places that you can go (especially online) to find cheap water heaters. Before you buy a new unit, determine how much water you use. If you have a big house or use a washing machine and dishwasher, and if you often have two showers running at the same time, you will probably need a 50 gallon plus water heater.
Please leave any comments in the section below.
This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.
© 2008 Handyman Pro