This is a complete guide on AO Smith Electric Water Heater Troubleshooting. Throughout this article, I will introduce you to common problems of the AO Smith electric water heater, including:
- Not hot water
- Not enough hot water or slow hot water recovery
- Temperature too high
- Drips from T&P Relief Valve Discharge Pipe
- And more
The best part is- I will also provide the solutions to those problems so that you can run the hot water trouble-freely.
So, let’s dive in.
AO Smith Electric Water Heater Troubleshooting [5+ Solutions]
Every electric appliance starts malfunctioning over time. And your AO Smith electric water heater is not an exception to that. And this chapter will break down the common problems of an electric hot water heater.
01. No Hot Water
Reasons that cause your AO Smith electric water heater to produce no hot water are:
- The unit receives no electric power
- The upper heating element gets burnt out
- A broken upper thermostat or its wiring gets damaged
- The energy cut-off switch gets tripped
- The Inlet and outlet connections of the water heater are reversed
- Produce little to no hot water because of a leak in the hot water side of the plumbing system.
How To Fix:
It’s a common issue that your AO Smith Electric Water Heater gets no electric power if you newly install the unit. So, start with checking the electric power to your unit. Just get a non-contact circuit tester and follow the below guidelines:
- Turn your water heater off at the circuit breaker.
- Remove the cover of the junction box. You can find it at the top of the water heater.
- Identify the two wires- the power wire and the ground wire. The color of the power wire is black/black or black/red. On the other hand, green or copper wire is the ground wire.
- Now, turn on your circuit breaker and use a non-contact circuit tester to inspect the power on both incoming power wires.
- Finally, shut off the power and put the cover back on the electrical junction box.
Without second thoughts, call a certified electrician to check your home’s wiring and circuit breaker if you get no electric power to the unit.
Secondly, you get no hot water from your AO Smith Electric Water Heater if the upper heating element gets burnt out. It’s very common for new installations. The upper heating elements get fried out if you mistakenly power on the unit without filling the water heater.
I highly recommend you inspect the heating element electrically before jumping the gun on replacing the part. Follow the below steps to test the heating element:
- Shut off the electric supply to your water heater at the circuit breaker.
- Use a flathead screwdriver to pull out the upper access panel.
- Remove the insulation to access the upper thermostat and heating element.
- Ensure there is no electric power by placing the circuit tester on the top two screws of the upper thermostat.
- Then, disconnect two power wires from the upper heating element.
- Place the two probes of your multimeter between the two screw terminals on the upper heating element. The resistance of a healthy heating element should be 5 to 25 Ohms.
If the resistance of the heating element goes out of range, you must replace the upper heating element. Regarding this, you can find the below tutorial useful:
On the other hand, you must reattach the power wires and ensure the wires are in good condition if the resistance is within the range. Also, make sure the wire connections are clean & tight.
Thirdly, check the upper thermostat or its wiring for damage. If needed, replace the upper thermostat along with the wiring.
Fourthly, inspect the energy cut-off or reset button for a trip. Basically, the ECO or the reset button is a safety feature of an electric water heater. If the water temperature in the tank gets too hot, the ECO button gets tripped to shut off the power to the heating element.
To check the Energy Cut-off (ECO) switch, turn the electric power off to your water heater. Then, remove the upper access panel. Next, take the insulation out to access the reset button. Now, press the red button (it’s the ECO or reset button) and have your ears hear a click. If it clicks, you successfully reset the ECO button.
Keep in mind; the ECO button will trip if it senses too hot water. So, call a professional to inspect what causes the water too hot.
If you press the reset button but don’t hear a click, I bet there is a problem with the upper thermostat. In this case, you should call a qualified technician to handle this issue.
Fifthly, ensure the inlet and outlet connections are in the correct position.
And finally, check the hot water side of the plumbing system for a leak. If you fail to trace the exact leaking point, hire a plumber to make this task easy for you.
02. Not Enough Hot Water or Slow Hot Water Recovery
You will get insufficient hot water output out of your AO Smith Electric Water Heater due to the following reasons:
- Defective thermostatic mixing valve in a faucet or shower control
- You may set one of the thermostats too low.
- The capacity of your water is too small.
- The dip tube gets melted
- A bad lower heating element
How To Fix:
Many shower controls now have thermostatic mixing valves. If they fail, the shower controls reduce the amount of hot water the shower or the faucet provides even though there is enough hot water in the tank.
I suggest you check the water temperature at several water faucets to ensure the problem is not in the faucet or the shower control.
2ndly, check the thermostats of your water heater to ensure you set them to hot settings. Most electric water heaters have two thermostats- upper and lower. Before adjusting the temperature, make sure you turn the electric supply off to your water heater.
To adjust the temperature, remove both the upper and the lower access panels. Then, folded away the insulations. Now, turn the temperature dial clockwise to increase the temperature.
You must set both thermostats to the same hot settings. Next, put the insulation and the access panel covers back into their places. Finally, turn on the electric power and wait for two hours to heat up the water.
3rdly, if the demand of your home is more than the capacity of the water heater, you will get insufficient hot water. So, install the correct size water heater based on your needs.
4thly, take a look at the dip tube for damage. If the dip tube gets deteriorated, you must replace it. Regarding this, you can find the article on Rheem Dip Tube Replacement helpful. Though the brand is different, the replacement procedure will be the same.
5thly, you should check the lower element for damage. If it gets faulty, replace it with a new one. The following video will come in handy if you don’t know how to replace the lower heating element.
03. Temperature Too High
If you set the thermostats too high, you will get excessive hot water out of your AO Smith Water Heater.
Besides, a malfunctioning thermostat or a shorted heating element is responsible for getting too hot water. If the T&P valve releases a large amount of hot water, I am pretty sure the shorted heating element is the culprit behind this.
Your AO Smith Water Heater will also produce excessive hot water if the thermostat doesn’t fit snugly against the tank.
How To Fix:
First off, check the thermostats to see whether you set them too high or not. If yes, adjust them.
In this case, turn the electric power off to your unit. Remove both upper and lower access panels and fold away the insulations. Now, turn the temperature dial counterclockwise to decrease the temperature.
Once you set the temperature according to your desired settings, replace the insulation and the access panels in their places.
Secondly, you must replace the non-functioning thermostat or the shorted heating elements to solve the excessively hot water issue.
And thirdly, ensure the thermostat fits your water heater snugly. If not, call a professional to fix this problem for you.
04. Drips from T&P Relief Valve Discharge Pipe
The T&P Relief Valve Discharge Pipe will drip if there is high water pressure. Turns out, if you installed a thermal expansion tank but pressurized it to the wrong pressure, you can see drippings coming out of the T&P Relief Valve Discharge Pipe.
In rare cases, the T&P Relief Valve Discharge Pipe will drip if dirt & debris gets stuck inside the T&P relief valve.
How To Fix:
If there is the high water pressure in your home, installing a Pressure Reducing Valve will be a simple fix to stop the drippings. Just install the PRV on the main cold water supply line. Then, set the pressure of the PRV between 50 to 60 PSI.
On the other hand, an electric water heater installed with a thermal expansion tank may also cause the T&P valve to drip if you pressurize it to the wrong pressure. Check the manual that comes with the thermal expansion tank and pressurize it to the correct pressure.
Finally, operate the T&P relief valve manually to make sure the waterways are free of dirt & debris.
05. Low Water Pressure
Get low water pressure on your AO Smith Water Heater!
Generally, melted heat traps or dip tubes are the culprits behind this issue. Soldering copper pipes while they are attached to the water heater can melt the heat traps or the dip tube.
These melted parts can restrict the flow of hot water. As a result, it will create a low water pressure issue.
Another reason that is responsible for low water pressure is- a partially closed supply valve.
How To Fix:
Begin with inspecting the condition of the heat traps inside the hot water and cold water connections. If they get melted, replace them professionally. Also, don’t hesitate to change the dip tube if it is at fault.
Then, take your eyes to the closed supply valve of your water heater. Ensure you open this valve fully to let water flow freely.
06. Water Odor
The tap water contains harmless bacteria. When it goes into your hot water, the bacteria can multiply and leave a ‘rotten egg’ smell.
How To Fix:
Chlorination is an effective treatment to eliminate the bacteria from the water. However, replacing the standard anode rod of your water heater with a special zinc anode rod may help in reducing the odor. I recommend you call a certified technician to do this workflow.
How to turn on the AO Smith Electric Water Heater?
Follow the below steps to turn on AO Smith electric water heater:
- Ensure the electric supply to the water heater is off.
- Remove both upper and lower access panels and pull out the insulations.
- Turn the temperature dial clockwise to increase the water temperature. Adjust the temperature according to your desired setting.
- Replace both insulations and the access panels to your water heater.
- Turn on the electric power to your water heater.
- Wait for several hours for a tank of cold water to heat up.
- Check the water temperature at several usage points like the bathtub faucet, shower, or lavatory sink.
How do I reset my AO Smith electric water heater?
Resetting an AO Smith electric water heater is simple. The steps you should follow to reset the unit are:
- Turn off the electric power to your hot water heater at the circuit breaker.
- Use a flathead screwdriver to remove the upper access panel.
- Remove the insulation to access the red reset button.
- Press the red button inwards. If you hear a click, you successfully reset your water heater.
- Finally, put the insulation and upper access panel back into their places. Next, turn on the electric power to your water heater again.
Why is my electric water heater not heating up?
Your electric water heater won’t heat up if the unit gets no electric power or the circuit breaker gets damaged. Besides, defecting heating elements and a tripped reset button or ECO switch are other caveats behind this problem.
Is there a reset button on my AO Smith water heater?
Yes, there is a reset button on your AO Smith water heater. You can find it on the upper thermostat. Just remove the upper access panel and take out the insulation. Now, you can see a round red button, which is known as the reset button.
We can’t think of a single day without a properly functioning water heater. You can feel the importance of a water heater when you go to take a shower but get no hot water.
And this guide on AO Smith Electric Water Heater Troubleshooting will come into play to solve the common problems you are experiencing. I broke down everything you need to know when your water heater is not functioning properly.
So, it will be worth bookmarking this article on your browser and getting it whenever you encounter a problem with your AO Smith Water Heater.
Eric Alvarez is an HVAC guy based in El Paso, Texas, United States. He obtained his Bachelor of Science degree from the University Of Texas at El Paso. Years of experience in the HVAC field have taught him many lessons, not the least of which is that the value of quality and knowledge far exceeds any promised initial savings. He has a good standing reputation for superior skills in heating, air conditioning, hot water tanks, and indoor air quality systems.
2 thoughts on “AO Smith Electric Water Heater Troubleshooting”
My A.O. Smith electric water heater is under 2yrs old and stopped working. I checked the breaker it’s was fine but there is something liquid black coming out of where the electric hooks in and I have no idea what it is. I have a photo of it if that would help
Hey, Connie Valentine,
Please share the photo with me.