AO Smith Water Heater Leaking From Top (Fixed)

Is your new AO Smith water heater leaking from the top? These appliances are known as some of the best in terms of reliability and safety. However, that doesn’t mean they’re without fault. All water heaters encounter various hardware issues, so it’s important to know what to do when your AO smith water heater is leaking.

If your AO Smith hot water heater is leaking from the top, there’s likely a loose fitting around the inlet or outlet pipe. Excessive condensation is another possible cause. Overheating and expansion can cause leaks through small holes anywhere on the water heater, including from the top.

Throughout this article, we’ll explain why your AO Smith water heater is leaking from the top, what you should do, and whether or not you need to shut off the appliance.

top of AO smith water heater

Why Is Your AO Smith Water Heating Leaking From the Top?

Your AO Smith water heater is leaking from the top due to loose fittings, a broken pressure relief valve, and hairline fractures. Other common causes include plumbing leaks and excessive condensation from running the water heater on a freezing night. Repair Clinic explains some drain valves leak from mineral clogs, too.

Let’s take an in-depth look at each of these probable causes below.

  • Loose fittings: Your water heater has an inlet pipe and an outlet pipe. Both of these pipes have fittings that secure them to the water heater. Minor vibrations from regular operation loosen these fittings. When the fittings get too loose, they drip water all over the top of the appliance.
  • Broken pressure relief valve: The pressure relief valve is designed to release built-up pressure within the water heater. You can manually open it to remove the pressure, but some AO Smith water heaters naturally release pressure. When the valve breaks, the water drips out of the top of the tank.
  • Hairline fractures: Small cracks along the top of the water heater typically occur after several years of continuous use. AO Smith water heaters are quite durable, but direct force can lead to tiny fractures. These holes leak water wherever they form. This can also occur due to excessive amounts of rust and corrosion.
  • Plumbing leaks: The previously mentioned inlet pipe and outlet pipe can have leaks within the plumbing. Most water heater plumbing has elbows, 90-degree fittings, couplings, etc. Whether they’re welded or glued with PVC pipes, there’s a chance that a leak could form and drip from the top of the water heater.
  • Excessive condensation: If you live in an extremely cold climate, there’s a high chance your water heater will have a bit of condensation. The good news is that condensation drips aren’t leaks. If there’s condensation on top of the water heater, it’s likely because the outlet pipe is hot compared to the cold air outside of the pipe.
tightening fittings on AO smith water heater

How to Stop an AO Smith Water Heater Leak

To stop an AO Smith water heater leak, follow these steps:

  1. Turn off the water heater before inspecting or repairing it. Fast Water Heater explains that it’s crucial to turn off any water heater prior to working on it because you could risk electrical shocks. Close the water line going to the water heater, too. The last thing you want is to open the water heater and dump hundreds of gallons of water.
  1. Let the AO Smith water heater cool down, then check the pressure relief valve. It’s almost directly on top of the water heater. Open the valve, ensuring your face is far away from the outlet. Wear safety gloves and goggles to protect yourself from potentially scalding water. Close the valve once the pressure is out of the tank.
  1. Look for hairline fractures on top of the water heater. They typically form around seams, such as the edges of the tank or right around the fittings. They could also form at the base of the aforementioned pressure relief valve. These small cracks can often be repaired with two-part epoxies.
  1. Tighten the fittings around the inlet and outlet, regardless of their locations. Check the user’s manual to know if you should hand-tighten them or use a wrench. Most AO Smith water heaters require a wrench since they have metal fittings. However, you should steer clear of wrenches if your water heater uses PVC fittings.
  1. Check for leaks above the water heater, such as in the plumbing or the ceiling. All plumbing leaks should be cut out and replaced with new pipes and fittings. Never use glue to cover a plumbing leak. It won’t do anything in the long run. Water heaters produce tons of pressure, so they’ll blow through the glue in no time.

All water heaters experience problems every now and then. However, it’s important to find one of the solutions mentioned above to prevent the leak from worsening. If your AO Smith water heater is leaking and none of these suggestions worked, we highly recommend contacting a licensed professional.

Should You Turn Off the Water Heater if It’s Leaking?

You should always turn off a water heater if it’s leaking. If your AO Smith water heater leaks from anything other than condensation, the first thing you need to do is turn off the gas, power, and water flow. Failure to do so can cause long-lasting, expensive damage.

Hot Water shows most AO Smith water heater leaks come from small holes that are very difficult to identify if the water heater is on. Thermal expansion can cause these cracks, but you won’t notice them unless the power is off and there’s no water running through the unit.

Final Thoughts

AO Smith water heaters are easy to repair if you know a little bit about plumbing. They have inlet and outlet pipes, both of which have small fittings that can loosen over time. By tightening or replacing these fittings, you can almost always solve the problem. Keep an eye out for leaks around seams and weak points on top of the water heater.