Water Heater Leaking: What You Need to Know

A hot water heater leaking on the floor is generally a millstone around the neck especially if you know nothing about troubleshooting the problem. You’ll be in a real pickle when you find one dripping your floor wet. Well, are you going to call a professional or are you up for some DIY troubleshooting?

You may not have given it much thought, but the water coming into your home passes through a system of pipes, and most often than not, it is cold or cool depending on the climate you have. To make it warm for a hot shower or bath or for your dishwasher use, you will need a device to heat it up. So enters the water heater. But what should you be concerned about if a pool of water suddenly appears on the floor at the bottom of the tank?


Diagnosing Your Hot Water Heater Leaking

If you think you can disregard hot water heater leaking as a minor nuisance, think again. It could be a symptom of a much bigger problem. You cannot adopt an ostrich strategy when your heater failure can very well likely damage your property and lead to expensive repair bills. To avert this threat, do not wait for the leaking to get worse. Find out the source of the problem then identify whether you can repair it yourself or you need the expertise of a handy man.

Best advice: Proper practice of maintenance helps prevent future water leak from your heater.

This information will guide you through diagnosing the source of the problem.

Steps to Diagnosing Leaking Source

Step #1. Find the source of the leak.

A pool of water on the floor or at the base of the hot water tank does not necessarily mean your heating device is leaking. The hot water tank plus the pipes around it and the other appliances or household devices functioning nearby can definitely form condensation especially during damp weather.

Condensation often scares the owners when they see water at the base of the tank. It may seem that a leak in the tank caused it.

When you have a lot of cold water in the tank, because it is used quite often, condensation can form and then drips onto the floor.

How to tell a condensation from a real leak:

  • You can see only a very minimal amount of water and then it stops when the tank heats up. A few minutes and the dripping are gone. If it dried up, then you don’t have a leaking hot water tank.
  • If the dripping persists after a few hours even if the tank has heated up and it continues to do so the following day, then this is bad news for you. You might have a leaking water heater.

Water softener discharge lines, furnace drain lines and other plumbing concerns may also be the source of the leak. A simple observation will help determine the problem. If you notice a small amount of water at the base of the hot water tank for the first time, wipe it up then observe if the water reappear.

Water is not immune to the laws of gravity. Pay close attention to its plumbing fittings, water pipes and anything overhead for any obvious signs of leakage.

If the source is not from these parts, lay down paper towels over the damp area and come back after a few hours to check on it. If the problem does not resurface even after a day, then it’s nothing to be concerned about. If it does show up and you cannot identify the source, then the hot water tank leaking is the cause.

Check out my these in-depth guides about water heater leaking from top and leaking from bottom.

Step #2. Turn Off Power Supply

Once you determined that your water heater is the source of the leaking, immediately turn off its power supply.

Locate the circuit breaker and switch off the breaker if you have an electric one. This is imperative since the combination of water and electricity can be extremely dangerous. A natural gas water heater should have an on/off switch or dial. Set the switch or dial to “off” while avoiding closing the gas shut-off valve if possible. This is because valves are prone to failures and should be best left alone.

Step #3. Turn Off Water Supply

If the leaking is significantly obvious, you will need to turn off the cold water shut-off valve to cut off water supply. You will need to pull down the valve handle or turn clockwise if it is a dial to turn off the water supply. However, it is EXTREMELY important to make sure that you do not come in contact with any water when you are closing the valve.

Water heaters are factory-set to 125 Degree Fahrenheit which is hot enough to cause first degree burns. When the water heater is running to its maximum temperature of 160 to 190 Degree Fahrenheit, serious injuries can ensue even without direct contact with the water. Always take precautions not to come into contact with the heated water.water-heater-cold-water-shut-off-valve

If the leak is serious and you cannot reach the water shut-off valve, locate the main shut-off valve that generally controls water supply to the house and close it up to stop the water from going to the water heater. This should slow the leaking and even stop it depending on its source.

Step #4. Identify Exact Location of the Leak.

Possible location of the leak includes:

  1. Check cold water inlet and hot water outlet points where the pipes are connected to the hot water tank. If minor leak is found, tighten loose connection with a wrench.
  2. leaking-hot-water-heater-TP-150x150Check the Temperature and Pressure Relief Valve (T&P valve). This valve helps lessen too much pressure in the tank by letting out water to relieve pressure. Inspect the valve and the point where it enters the tank and see that it is watertight. If this valve is the source, the water will drip down the plastic pipe which is attached to it when it is in closed position. This could either mean that the valve is defective or it is working properly releasing pressure inside the tank causing it to open. This is a fixable problem.
  3. Leaking-Hot-Water-Heater-Drain-Valve-150x150The heater drain valve near the bottom of the water tank should also be inspected. It should close completely and its entry point into the tank is watertight. If this is the source of the leak, the problem is not serious.
  4. If the problem is the bottom of the tank, then the only fix is to replace your water heater altogether. An internal leak is likely to escape at the bottom of the tank and this is usually due to age and deterioration, rust or corrosion. This may not be visible from the outside since the tank is wrapped inside insulation and covered with an outer skin. A closer inspection can help identify this problem.

You can watch this video from The Plumberologist to learn more!


Hot water tank leaking can cause more serious problems to your house since water can seep through your floors, sub floors and walls. Leaking problem can also be a health concern. Wet or damp areas can breed molds and mildews that can cause allergies and asthma, and some of these molds spores out toxins leading to more serious health problems.  If you find your hot water tank leaking, best move quickly to fix the problem for more information take a look at h2ousegeek.com for all your water leak problems.