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Solved: Why Is My Hot Water Heater Leaking Water?

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If you come home to a puddle of water under your water heater it’s time to take a closer look. Water leakage can be a sign that there is something wrong with your water heater and it needs attention. We will discuss some of the most common reasons why hot water heaters leak and what you can do about it. We also have some helpful tips and insights on how to maintain your water heater so that you can avoid any costly repairs in the future.

Step 1: Ruling Out Condensation

You see water on the floor around your water heater and know you might have a problem. First, you need to rule out other causes of water. Condensation can be a potential cause of water around your water heater.

Condensation on a Gas Hot Water Heater

High-efficiency gas water heaters can produce condensate that is harmless but can look like a leak. Here is how to identify condensation:

  • Wipe up water under the heater
  • Turn the gas control valve to the OFF position
  • Wait for several hours to see if it is wet again under the heater
  • No water means that the heater was condensing

Condensation on an Electric Water Heater

With an electric hot water heater one cause of condensation is the hot cylinder tank being located in a cold room. You can test for condensation by wiping down the outside of your hot water heater and then watching to see if the moisture comes back in an even pattern across the water heater surface. If it does then it is most like condensation.

Look for Other Causes

If your HVAC system is in the same room as your hot water heater make sure that the source of the water leakage isn’t coming from your AC or furnace or any other connected systems like water softener lines. Also check the water supply lines that bring water to your water heater. Leaky lines or pipes located above or below the water heater might be the problem (keep reading to learn about fixes).

Step 2: Turn Off Power Supply

Once you have determined that the water heater is leaking, turn off the gas (for gas heaters) or the electricity (for electric heaters). Water and electricity don’t mix so this is a crucial step you don’t want to skip, ever! If you aren’t comfortable working with gas or electric water heaters then now is a good time to call in a professional. And don’t mess with any gas piping – leave that to the experts.

Locating Your Gas Shut-Off Valve

There are typically instructions on the front of your water heater explaining how to turn off the gas valve. If you can’t find it there, then look for the shut-off valve near your water heater. It is usually located at the top of the heater and will have a knob or lever that you can turn to completely turn off the gas supply.

Locating Your Power Breaker

If you have an electric water heater make sure the circuit breakers are off in your electrical panel. If you can’t find which breaker controls the water heater, look for a label on your electric panel or use a diagram on the door of your panel to help identify the correct breaker. Once you have found it, switch the position to OFF.

Step 3: Turn Off Water Supply

Another safety step is turning off your water supply entirely. To do this, locate your main shutoff valve and turn it off. This is usually found either in the basement or outside near the curb.

In addition to shutting off your water supply at the main line, you should also turn off the cold water supply for your hot water heater. To do this, look for two valves on your hot water heater, one for hot water and one for cold. Your hot water supply is typically marked in red and your cold water supply is usually marked in blue. Shutting off the cold water will help to prevent any further water damage from leaking water.

Step 4: Establishing The Source of Your Leak

Now that you’ve shut off gas/electricity, your main line, as well as the cold line supply it’s time to figure out the source of your water heater leak.

Common Reasons for a Leaking Water Heater

The most common cause of water heater leaking is a damaged or failing pressure relief valve. This valve prevents pressure from building up in the water tank, and when it fails, hot water can start to leak out. Other potential causes could include:

  • A cracked or corroded water heater tank
  • Loose or faulty fittings and pipe connections
  • Improperly installed temperature and pressure relief valve
  • Worn out anode rod to protect the hot water tank from corrosion

It’s important to determine if one of these causes is behind your leak in order to make the necessary repairs yourself or determine if a professional needs to be called.

Water Leaking From The Top

Pooling water from the top of your water heater could be your cold or hot water inlets that bring water into the tank to be heated and then out into your pipes when you need it. Loose pipe connections can cause leaking from the top of your water heater.

Solution: tighten the cold and hot water inlet pipes with a pipe wrench

Water Leaking From The Side

Water leaking from the side of your heater is likely your temperature pressure relief valve. The temperature pressure relief valve is a safety mechanism that allows for hot water and steam to discharge from the tank when there is too much pressure built up inside it.

Solution: Check the temperature to make sure it isn’t set above the recommended 120 degrees. If the temperature is set correctly and continues to leak, the valve is defective and needs to be replaced.

Water Leaking From The Bottom

If you notice water leaking from near the base of your water heater, it could be an issue with the drain valve. The drain valve is designed to empty the water tank when needed, such as during maintenance.

Solution: Inspect the drain valve for corrosion and replace. If there is no corrosion, tighten the valve slightly but don’t over do it because it can cause damage. If tightening does not fix it, replacement may be necessary.

Other Possible Issues

If you still have unexplained water pooling underneath your hot water heater it could be due to a bad anode rod or a crack. To find out if an anode rod is your issue requires some work that often means calling a professional. Sadly, if your leak is due to a crack in your hot water heater it isn’t a quick repair. You are going to need a new water heater. In both these situations the best thing to do is call a professional and get an assessment of what is going on and determine next steps.

Additional reading: 10 Noticeable Signs Your Water Heater is Going Bad

Step 6: Avoid Future Issues with Regular Maintenance

If your hot water heater is leaking but not showing any of the issues listed above, it may be due to a build up of sediment or mineral deposits. It’s important to flush your water heater annually as part of regular maintenance and preventative care. This can help avoid the need for costly repairs due to build up and reduce the risk of a leak.

To keep your hot water heater running efficiently, you should also check it regularly for any signs of leakage or damage. If you do notice a problem, contact a professional immediately to assess the issue and make sure your hot water is safe to use.

By taking the time to maintain your water heater and check for any signs of damage, you can avoid costly repairs due to a leaking system and keep your hot water running smoothly.

Additional reading: How Long Do Water Heaters Last?

Repairing or Replacing Your Water Heater

Water heaters are an essential part of keeping our homes comfortable but they need regular maintenance. If you start to notice water leaking from your water heater, it’s important to take action quickly. Inspect the system for visible signs of damage and if your water heater is over 10 years old or you find yourself repairing often it might be time to contact a professional for a water heater replacement.

A new water heater comes with a host of advantages:

  • high energy efficiency heating
  • improved safety features
  • energy savings
  • warranty

The cost of a new water heater, whether it’s a tank or tankless heater, may seem intimidating but the long-term savings on monthly energy bills and peace of mind will pay off in the end.

Additional reading: How Much Does it Cost to Replace a Water Heater?

Jacobs Can Help Diagnose Water Heater Leaks in Your Portland Home

Determining next steps when your hot water heater isn’t working right can be daunting. Jacobs Heating & Air Conditioning experts are here to guide you through the process whether it is a water heater repair or a replacement.

Extend the life of your water heater, avoid extra costs and fewer repairs by scheduling a tune-up for your existing system before issues arise. Our maintenance plans keep your water heater running like clockwork without any stress or hassle. No matter what you need we’re always just a phone call away.

About the Author

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Amanda Jacobs, Internal Project Manager

Amanda Jacobs is an Internal Projects Manager and 3rd generation member of Jacobs Heating & Air Conditioning. She received her MBA from Seattle University and has worked for a leading HVAC training and consulting firm. When not talking HVAC on the Jacobs Blog, you can find her on the golf course or whipping up her famous vegan chili.