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1Discovering that your hot water tank is leaking from the bottom is something you need to deal with right away. Your water heater leaking is likely happening for one of three reasons. Either way, depending on what is causing the leak, you will need to act fast. Here is what to do when you have a water heater that is leaking from the bottom.

Hot Water Tank Leaking From Bottom

How to tell if your hot water tank leaks from the bottom

Before we begin, hot water tanks contain enormous pressure and extremely hot water. Because of this, we recommend contacting a professional to inspect your hot water tank. However, if you choose to do this on your own, please take all the precautions as the water can cause severe damage and burn you.

Step 1: Dry the area

Determine where the water heater leak is coming from. The best way to do this is to dry the area with a towel and see if any water begins to gather.

Notice where the water heater leak is coming from. It will usually be from one of three places. Once you see where the leak is coming from, you will need to take action quickly.

 

Step 2: Turn off power to the tank

circuit breaker panel

Before doing anything else with your water heater leaking, make sure that there is no power going to the water heater. There are two different kinds of water heaters, here is how you turn off each of them. 

Electric Water Heater Tank

If you have an electric hot water tank, the best thing to do is to turn off the power at the breaker before doing anything with your tank. Simply find your panel and switch the breaker off.

Gas Water Heater Tank

If you own a gas tank that is leaking, shut off the gas before working on the tank. There will be a dedicated gas shut-off valve on the line going into the tank. This is standard for all gas water heaters. Simply put it to the off position. If you believe that you may have a gas leak, turn off the gas and contact a professional right away.

 

Step 3: Turn off the water supply

Your water heater gets its water from the cold water supply. It should have a shut-off valve at the cold inlet. Turn the lever to the off position.,

If your tank has a wheel on it, turn it clockwise until the water shuts off. At this point, you do not need to drain the tank.

Once the water lines are off, you can take a closer look to see why your water heater is leaking from the bottom.

 

What causes your water heater to leak from the bottom?

There are a few places where water heater leaks can occur. You may not have noticed immediately, but perhaps you’ve had hints like low hot water pressure or dampness in the basement. Whenever water is involved, it’s important to deal with it right away to avoid water damage

Here are the places you want to inspect for the root cause of your leak.

Internal tank

Your hot water tank consists of two separate tanks. There is the internal tank, which is covered with insulation, and then the outer tank, which is the one you see.

If you have an internal water tank that is leaking, you will not be able to see it as it is covered by the outside tank.

The internal part of the hot water tank may be damaged. This is usually caused by a variety of reasons, such as a faulty tank or the tank not being properly maintained. You may have noticed this starting to happen over time if the hot water in your house is not as hot as it used to be.

When an internal tank leaks, it will come out of the bottom of the water heater. There is no way to replace an internal water tank. The best thing to do is drain it, hire a plumber to install a new one, and have them take the old one to a scrapyard in the area.

If you have had your water heater for over a decade, your tank may need to be replaced.

 

Click Here to Find a Local Plumber

 

 

Drain valve leak

When I first saw water leaking from the drain valve, I had to Google, “Why is my heater leaking from the bottom drain valve?” It turns out that the bottom valve commonplace for water to leak.

Hot Water Tank Leaking From Bottom drain valve

Your drain valve is where you drain the hot water tank when you perform maintenance on your hot water heater. It’s also where you empty the tank and remove any sediment that gathers.

If there is a loose drain valve, water can start to drip out of it, causing your tank to leak. The leaking drain valve may also be loose (as was our case). A slight turn with a plumber wrench tightened up the valve, and the dripping stopped.

If that doesn’t work, check to make sure there is nothing blocking the leaking drain valve, such as sediment from the inside of the tank. The best way to do this is to flush the drain.

Flush the Drain Valve

water heater drain valve

To flush the leaking drain valve, attach a garden hose to it and open the valve for a few seconds to flush out anything that may be preventing the valve from properly closing. Do this by turning the dial clockwise from its closed position. 

If tightening the valve doesn’t work, the next step is to replace it with a new drain valve. If you leave it, the tank will continue to drain water and could result in water damage to your basement.

To replace the drain valve, you will need to drain the tank first. You can do this by connecting a hose to the existing drain valve and running it down a drain.

Next, you can remove it with a wrench and turn the dial counterclockwise.

Then, take the new valve and put on some Teflon plumbers tape. Make sure to put about 5 turns on it and work the tape into the groves of the valve.

Then, turn the new valve counterclockwise until it is snug first by hand and then use a wrench to do the final tightening.

Turn the water back on to see if there is a leak. If not, you have fixed the issue.

 

Leaking overflow pipe (T/P relief valve)

water heater discharge tube

This is the discharge tube that is connected to the temperature and pressure relief valve (aka T & P valve). If the pressure builds up in the water heater tank, this valve will relieve the excess pressure and will look like your water heater leaking from the bottom.

The pressure relief valve is a part of your tank to relieve pressure when there is excessive heat, excessive water, or too much pressure in the tank. The TP valve can be on the top or the side of the water tank and will have a pipe coming from it running down the side of the hot water heater so that the water can drain out to the floor.

A heater leaking from the bottom via the TP valve isn’t a bad thing, it’s actually there to help prevent the water heater from leaking. By releasing the excess pressure in the tank it ensures the entire tank has a longer life. 

A leaking pressure relief valve can make it look like water is coming out of the bottom of your water heater, when in fact, it’s only coming out of the tube at the bottom. The leak itself is coming from the top. 

Check the inside of the tube to see if there is moisture; if there is, your temperature and pressure relief valve is likely the culprit.

This could mean that you have the temperature and pressure relief valve on your water heater that needs to be changed.

You can replace the TP valve, but it’s best to contact a plumber who can assess the situation and decide what is best for your water heater.

 

What to do after you have identified where the water is leaking from the bottom of your water heater

Once you know the source of the bottom leaking water heater, you can deal with it.

For a drain valve and TP relief valve, you can attempt to change them on your own if you have previous experience. An internal leak means you will need to replace the whole tank.

For most homeowners, it’s best to hire a professional such as a licensed plumber, as you are dealing with dangerously hot water and pressure.

To find a licensed plumber in your area to fix the water heater leaking, use the link below.

 

Click Here to Find a Local Plumber