Is Your Water Heater Leaking From the Top or Bottom? (Complete Guide)

Last Updated On September 25, 2022
water heater leaking Do this to fix leaks from top or bottom

You don’t necessarily know when or why, but your water heater started leaking! 

What does a leaking water heater mean, and what can you do to resolve the problem? 

Water heater leaks can occur from the hot water tank, the top of the water heater, or the bottom of the water heater. 

Identifying the location of the leak can help you diagnose the cause of the leak and allow you to take the proper action. 

In this PlumbingNav guide, we will cover: 

  • Locations and causes of water heater leaks
  • How to resolve water heater leaks
  • Can you safely use a water heater while it’s leaking? 

What's In This Guide?

      Hot Water Heater Leaking 

      The average home has leaks that accumulate 90 gallons of wasted water a year, and your water heater may be contributing to this water waste. 

      If you walk past your hot water heater and notice a leak, stop to examine the situation. You don’t need to panic quite yet, but the leak deserves your immediate attention for several reasons.

      A leaking water heater can lead to water damage, such as mold growth and the structural deterioration of your home. It also causes higher water bills thanks to all of the wasted water. 

      Leaks can occur whether you have a tankless water heater or a storage-tank water heater, so don’t assume you are safe because you made the upgrade to tankless

      What Should I Do If My Water Heater Is Leaking?

      If you notice your water heater leaking, follow these simple steps:

      Step One: Visually Inspect Leak

      When you first notice the leak, perform a quick visual inspection to determine the location of the leak.

      Leaks come from three possible general locations:

      • Bottom
      • Tank
      • Top

      Knowing the location of the leak will help you diagnose the problem, which we cover in detail a little bit later.

      Step Two: Shut Off Water

      Shut off the water to the water heater by closing the cold water supply, closing the shutoff valve, or shutting off the water at the main water line.

      Turning off the water prevents additional leakage while you fix the leak, which can lead to water damage.

      Step Three: Shut Off Power

      Next, turn off the source of heat. 

      For an electric water heater, you will shut off the electricity at the circuit box.

      For a gas water heater, you will shut off the gas supply. If the device uses an electronic ignition, you will cut off the power, too.

      did you know water heater leaking from bottom

      Step Four: Narrow in on the Problem

      Locate the source of the leak to focus your examination to one particular part of the water heater: the top of the water heater, the bottom of the water heater, or the tank. 

      Step Five: Tighten All Connections

      Sometimes, all you need to do to resolve a leaky water heater is tighten the device’s connections at the different valves and hoses. New water heater hoses are not expensive and are fairly easy to install.

      Step Six: Replace Damaged Components 

      When you go to tighten the connections, you may notice a component may be the main source of the problem. 

      You may need to replace the component, especially if it has visual signs of deterioration. 

      Step Seven: Enjoy Hot Water Again

      The last, but definitely not the last step, is to enjoy hot water again.

      Let this be your motivation to fix your water heater leak immediately.

      Is it dangerous to have a leaking water heater?

      In most cases, a water heater leak does not present a serious risk to your wellbeing.

      However, for the safety of everyone in your home, proceed with extreme caution. A leaking water heater can cause electrical shock if water comes into contact with wiring.

      Furthermore, a leak can mean the water heater tank contains too much pressure. Under worst-case scenarios, it could explode if you do not resolve the problem.

      Can you still use water if your water heater is leaking?

      We recommend fixing the leak before using your water heater again.

      Using the water heater can damage the water heater even more. Also, if the water heater does present a danger, using it only increases the risk.

      Water Heater Leaking From Top

      Do you notice your water heater appears to leak from the top?

      Luckily, a water heater leaking from the top tends to indicate a less extensive repair than a water heater leaking from the bottom.

      With that being said, water flows downhill, so the water damage can still wreak havoc.

      Where do water heaters leak from the top?

      Your water heater can leak from the top for the following reasons:

      Leaking Pressure Relief Valve (PRV)

      The pressure relief valve is a valve on your water heater that allows excess pressure to escape the water heater storage tank. 

      Leaking Cold Water Inlet Valve

      The cold water inlet valve allows you to control when water can enter your water heater tank. When open, new water will enter your tank as people use it. When closed, the tank will continue to drain with use until empty. 

      Leaking Hoses

      The water heater hoses transport the water from the main water supply to the water heater and the outlet supply line. 

      What Causes Water Heater Leaks? 


      In most cases, faulty valves become damaged due to corrosion. Corrosion refers to the natural chemical deterioration of metal materials over time that takes place even faster when pipes regularly come into contact with hot water. 

      An anode rod can slow down the corrosion process, but you need to replace it every 3 – 6 years. Anode rods attract the corrosive metals so that the rod becomes corroded instead of the tank. 

      There are three types of anode rods: 

      • Magnesium – high end, effective option that requires more frequent replacement 
      • Aluminum – standard option that costs less and lasts longer, but it’s not the most effective material available
      • Aluminum/zinc – best option for avoiding sulfur smell

      Sediment Buildup

      Sediment buildup occurs in a water heater over time, especially in areas known for having hard water. 

      Hard water refers to water that contains high levels of minerals, especially calcium. When water vapor turns into gas, it will leave behind the minerals it contained. 

      Poor Quality Materials

      High-quality materials last longer and protect against damage better. However, they also cost more. 

      Plastic valves generally don’t hold up as well as brass valves, and plastic hoses decline much quicker than metal hoses. 

      What Do I Do If My Hot Water Heater Is Leaking From The Top?

      Step One: Turn Off Power to Unit

      Safety first! Turn off the electricity and gas as applicable before performing any maintenance on your water heater.

      Step Two: Find Location of Leak

      Use your hand or a dry piece of tissue paper to find the exact location of the leak.

      At this time, you should still have the cold water valve open.

      Step Three: Turn Off Water

      Turn off the water to your device to eliminate the chance of flooding. 

      Step Four: Replace Damaged Component

      After you locate the source of the problem, you need to replace the damaged component.

      Before buying a component, such as a new valve, verify it is compatible with your device and made from mid-grade or high-quality materials. 

      Also ensure you have all tools you need, such as a wrench and Teflon tape. 

      Step Four: Perform Additional Water Heater Maintenance

      While looking for a leak, you have a great opportunity to catch up on general water heater maintenance as part of your annual plumbing checklist. (See this post for tips on maintaining a tankless water heater.)

      For both storage tank water heaters and tankless water heaters, flush the unit to remove sediment buildup.

      If you have a storage-tank water heater, you should also change the anode rod to eliminate corrosion.

      Step Five: Verify Problem Resolved

      Now, check to see that the problem is resolved by restoring fuel and water to the water heater and verifying you fixed the leak.  

      Water Heater Leaking From Bottom

      Do you notice your water heater leaking from the bottom?

      With important pipes leading to the bottom of the unit, these leaks require immediate attention to prevent a serious water heater problem. Most city codes require a drain pan as a safeguard against such leaks. A small leak might go unnoticed if water remains in the pan, and this may accelerate the corrosion of the bottom of your tank.

      Why Is My Water Heater Leaking From The Bottom?

      The two main reasons that your water heater is leaking from the bottom are:

      • Leaking drain valve
      • Leaking TPR discharge pipe (overflow pipe)

      If caused by a leaking drain valve, the hot water heater may not be able to drain properly when necessary.

      If the TPR discharge pipe valve leaks and creates a hissing or whistling noise, the unit contains too much pressure. Luckily, the pressure relief valve releases the pressure automatically after it senses high-pressure levels.

      However, if that pressure valve breaks and the device builds up too much pressure, it can lead to a devastating explosion.

      Pressure accumulation in the water heater tank happens when sediment buildup damages the heating element, causing excessively hot water temperature and high water pressure.

      Leak vs. Condensation

      It’s important to note that many water heaters create condensation when they get cold. If you notice water under a gas water heater, wipe it up and turn the water heater on. 

      If water accumulates under the hot water tank while the device is running, that indicates a problem with the unit. If the water doesn’t come back while it’s running, you probably saw condensation. 

      Condensation is normal, but you may want to consider a drain pan to collect the water and avoid puddles developing in your house. 

      Can you fix a leaking water heater?

      Both the drain valve and TPR discharge pipe leaks generally benefit from professional assistance. 

      However, if you recognize that the problem derives from a faulty drain valve, you can replace it yourself in a similar way to the valves on the top of the water heater.

      If unsure, stay safe and enlist the services of a professional plumber if you notice a leak coming from the bottom of your water heater.

      Preventing Hot Water Leaks

      Instead of making repairs or buying a new water heater after a leak occurs, do what you can to prevent the hot water leak in the first place. Follow these simple steps to prevent the hot water heater leaking.

      Replace Anode Rod

      Your tank-style hot water heater comes with an anode rod that prevents corrosion of the tank.

      You need to replace the anode rod every couple of years for optimal performance.

      Flush Water Heater Regularly

      It’s important to flush the water heater regularly to eliminate sediment buildup.

      To flush the water heater, you will open the water heater drain valve but continue to allow water to enter from the cold water inlet valve.

      Once the water runs clearly without any signs of sediment, you can close the drain valve again.

      A tankless water heater requires a special water heater flush kit with a pump to complete the task.

      Buy A Water Softener

      A water softener eliminates some of the minerals in the water that enters your home.

      Since soft water contains fewer minerals, you won’t find as many calcium deposits in the unit. 

      Final Thoughts on Leaky Water Heater

      If your water heater exceeds its life expectancy and starts to leak, especially from the tank, you should get a water heater replacement immediately. 

      Most water heater leaks from the bottom of the unit indicate a need for professional repairs unless you feel comfortable replacing the drain valve yourself (just make sure you didn’t mistake the leak for condensation!)

      You can tackle most water heater leaks coming from the top of the unit yourself, but make a point to keep an eye on the repair to ensure it fully resolved the problem.

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      About Plumbing Navigator

      We write about "all things plumbing," helping you navigate common questions, repairs, and the best plumbing products on the market.

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      We write about “all things plumbing,” helping you navigate common questions, repairs, and the best plumbing products on the market.

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