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Is Your Hot Water Heater Leaking From the Bottom? Here’s How to Fix It

By Author Kevin L. Sharp

Posted on Last updated:

One of the most irritating things that can happen to you is finding a pool of water underneath your hot water heater. Not only will this effect your hot water consumption, it can also damage your floors and lower walls by seeping in and causing mold to grow. When you first notice that your hot water heater leaking from the bottom, it’s highly recommended that you repair it as soon as can be. Whether you have an electric or a gas water heater that’s leaking from bottom, making use of the information below can save you quite a bit of money and trouble.

The temperature and pressure and relief valve

The first thing you will want to do is locate the leak. A good place to start is by inspecting the discharge tube that’s connected to the temperature and pressure and relief valve. This tube runs from the valve all the way to the bottom of the floor and ensures that if any water should happen to leak from the valve, it’s discharged safely below.

Once you locate the discharge tube, you’ll want to inspect the inside of it. What you’re looking for is moisture, and if you do in fact see that it’s wet, then your hot water heater is most likely leaking at the bottom due to a faulty temperature and pressure relief valve. To fix this issue, you’ll want to replace the valve or call a professional who can do it for you.

Check out: What to Do When Your Water Heater Pressure Relief Valve Is Leaking

The drain valve

Have you checked to see if your water heater is leaking from the drain valve? At the bottom of your water heater tank, you’ll find the drain valve. This valve allows the homeowner to drain the water from the tank. Start by inspecting this valve to see if there’s any water dripping from it. You’ll also want to see if there’s any water dripping from around the base of the valve as well.

If there is dipping, inspect the drain valve to see if it’s loose. If it is loose, you’ll want to use a wrench to tighten it up. It’s important that you turn the wrench clockwise until the valve is snug. You should also inspect to see if the valve system nut or the valve handle are loose as well. If these areas are loose, tighten them up using the wrench and turning it clockwise. However, if after you tighten up these areas you still have problems, you’ll want to go ahead and replace the faulty valve.

How to replace a drain valve

Follow the instructions below.

  1.  Turn off the power or gas supply to your hot water heater and shut down the water source by closing the inlet valve on top of your tank.
  2.  Get a garden hose and connect one end to the drain outlet and place the other end in a place safe for draining.
  3.  Locate the inlet valve and turn it off. This valve is usually located on the very top of the tank.
  4.  Now, let the tank drain by opening up the drain valve. Make sure you empty the tank all the way.
  5.  Equip yourself with a wrench. Begin to remove your old valve by twisting it counter clockwise with your wrench.
  6. Once you get the old valve out, it’s essential that you get some sort of plumber’s tape or joint compound and wrap it around the threads.
  7. Take your new replacement and begin to screw it in. You want to make sure you screw it in until it’s tight.
  8. Take your wrench and give it another small twist until it’s snug. Attach the garden hose to the inlet valve at the top of your tank and refill it up.
  9. Turn the inlet valve and the power to your hot water heater back on. If you own a gas water heater, you’ll want to light your pilot light.

The Overflow Pipe

If you’re still unsure what the problem is, you may want to check to see if your hot water heater leaking from the overflow pipe. When water leaks from the overflow pipe, it runs from the pressure relief valve down through the overflow pipe and onto the floor. The reasoning for this is because there’s too much pressure in your tank, and if it doesn’t get release, your tank could explode. This is a major danger to your house hold. To determine if the issue is in fact a pressure problem, you’ll want to:

  1.  Turn the thermostat to its lowest level.
  2. If your water supply and your power or gas is turned off, turn them back on.
  3. Watch your water heater for a few minutes.
  4. Look to see if water is still running out of the overflow pipe.
  5. If you still see water running from the overflow pipe, you will want to kill the power to your hot water heater and hire a plumber to inspect the unit.

Outer condensation

There are a few things that can cause condensation to form on the outside of your tank. This can happen when your tank is outdated, the insulation has been ruined or the thermostat was set extremely too high. To fix this problem, start by shutting down the power or the gas supply to your unit and let it just sit anywhere from 4 to 6 hours.

Once your water heater has been sitting for a few hours, check to see if you still have a leak or any condensation present on the outside of your unit. If you notice that the leak has come to a stop, you’ll want to lower the temperature of the thermostat and then turn the power or the gas supply back on. As your water heater runs over the next few hours, check to see if the condensation is still present. If you do still see condensation, that usually means that the insulation on the inside is damaged. If this is the case, you’ll want to invest in a brand-new unit.

An internal leak

Another reason your hot water heater may be leaking from bottom could be due to an internal leak. In most cases, a build-up of sediment is the leading cause of this. Overtime, if the tank is not regularly flushed out, this build-up can cause the tank to rust and spring a leak. It’s recommended that you flush your water heater tank out at least once a year. However, if your tank has been neglected and has already been damaged, it’s best to just replace the whole unit instead of trying to patch it up.

Preventive Maintenance

Like mentioned above, overtime your hot water heater can begin to clog up with sediment at the bottom of your tank. To keep your tank running smoothly, you should think about flushing your unit out at least once a year. This will help prevent your hot water heater leaking from the bottom. To do this, you’ll want to:

  1. Turn off the power or your gas supply to your hot water heater in addition to closing the inlet valve on the top of your tank.
  2. Attach one end of a garden hose to the drain valve at the bottom of your tank and stick the other end in a safe place to drain the water. Let the tank drain empty.
  3. Once the tank is empty, shut the drain valve and attach the hose to the inlet valve on the top of the tank.
  4. Refill the tank up to its appropriate level.
  5. Once filled, shut the inlet valve and turn the power or the gas supply back on. If you own a gas hot water heater, relight the pilot switch.

Your water heater tank has now been flushed.

Kevin L. Sharp
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