How to repair water heater leaking from the top and bottom of the tank, including drain and pressure relief valve. How to check and find common leakage points. Troubleshooting, cause, prevention, and DIY repair tips.
Since the leaking water heater is a common problem in both gas and electrical heating systems, the first thing you should do before buying one is to consider a location for its installation, so that the potential leak won't damage the property.
The first sign of the heater leak is a puddle of water on the floor and at the bottom of the unit. The good thing is if the water is dripping, the bad is if it is spraying or flooding the surrounding. Two of the most common spots where the water leaks or drips from are the temperature and pressure relief valve (TPR or T&P valve) located at the top of the unit and drain valve, found at the bottom. Other reasons include poor installation and lack of maintenance.
One of the main reasons why the water heater is leaking from the top is due to clogged TPR valve. Place a bucket under the valve and open it to release some hot water. This simple action can remove the debris found inside the valve. If this didn't solve the problem, this safety valve has to be replaced... and this is how.
The leak can also come from the loose connections, where the cold and hot water pipes are connected to the heater's body. You might have to use a pipe wrench to tighten the connections, re-seal or put some more Teflon tape.
One of the main reason why water is leaking from the bottom of the tank is the clogged drain valve or malfunctioning valve. If the unit was equipped with the plastic one, replace it with the more durable and reliable brass type.
If the reason for the leak is a rusty tank, there is nothing you can do there except replacing the unit.
As said, spraying or flooding is bad as there might be a pipe burst, a crack in a corroded tank or broken valves, so water can exit the tank in a short time and do damage.
Heating units should not be installed in the location where leaky water heater may result in property damage, such as the attic. One of the solutions might be the installation of the drain pan, water leak detector and shut off device. Sensors are used to trigger the alarm or to turn off the incoming cold water when the leaking problem is detected.
The drain pane should be installed at the same time as the water heater so it can catch potential drip from the pressure relief valve or loose connections. From the drip pane and through the installed pipe, water is removed to the drain.
If the water is found under the tank of the electric unit, you might want to check the gaskets on the heating elements. The insulation needs to be removed in the area of the electric elements to indicate dripping.
Condensation can also be considered as a leak, because of the amount of water and suddenness when it occurs. It usually disappears when the heater becomes warmer. The excessive condensation occurs during the colder months, winter and early spring. It usually affects the gas-powered heaters.
Note: Puddle of water is not always coming from the water heater. You might have leakage from other appliances or plumbing line. Do not replace the heater unless you did a full inspection and took corrective action like tighten threaded connections, replace broken parts. You might be able to fix the leak before scrapping it.
Keep in mind that leak can also be the symptom of a more serious problem, such as bulging, so calling a professional plumber makes more sense than DIY.