Hot Water Heater is Leaking from the Top: Troubleshooting and Repair Tips

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What to do if your hot water heater is leaking from the top? While this can be a cause for concern, it isn't something you should lose sleep about. Yes, a leaky water heater can be a huge problem and expensive to fix, but mostly it doesn't require you to go shopping for the new unit.

Generally, you can't afford to ignore a leak in the water heater because it will show up in the utility bill, reduce the performance or damage the surrounding. However, it isn't every leak that requires a replacement of a water heater.

A leak from the top of the water heater can easily be fixed. The important thing is to find out the exact spot that's leaking and get it repaired.

Water heater is leaking from the top: Finding the causes and solutions

Gas water heaterGas water heater

There are several reasons why your water heater is leaking from the top. We'll go through some of those below to help you know what to do once you discover the leak. If the water heater is leaking from the bottom, troubleshooting could also be easy for DIY-ers.

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How to repair a TPR (temperature and pressure relief) leak

Basically, when a water heater is leaking from the top, such as a TPR valve (T&P), you might need to get a new valve. If the problem is inside the valve, do not try to repair it, the valve is a safety device factory calibrated and tested for the proper work.

If the problem is at the connection where it is screwed into the tank, you might just have to add or replace the Teflon tape or joint compound.

If the leak is from the discharge pipe, which is connected to the T&P valve, the problem might be either due to the failed valve, which doesn't close, or the pressure and temperature inside the heater are too high, forcing the valve to open (this is normal).

Check the pressure, expansion tank, or elements.

The TPR valve is usually installed on the top or side of the tank. Watch carefully to see if there's water seeping out of the valve.

Although, one way to prevent such a leak is to ensure that you maintain the pressure and temperature within the recommended (operating range) and below the maximum allowed. That is, the water heater should have an average temperature from 120 to 130 degrees and up to 160 F, so it doesn't get too hot and pressure around 50-60 PSI.

The maximum value that the valve can deal with are found on the plate of the valve (for residential homes, it is 150 PSI). Also, the BTU that is designed for should not exceed the BTU of the water heater.

Note that replacing the TPR valve is relatively affordable and easy to do.

Water is leaking from the anode rod connection: Troubleshooting and repair tips

The anode rod is a long sacrificial rod screwed into the top of the water heater. The core is usually made of stainless steel.

There are several types, such as zinc, aluminum, and magnesium sacrificial type and powered non-sacrificial type.

It is designed to prevent the tank (made of metal) from corroding. Over time it deteriorates, losing its ability to reduce corrosion so that the connection might rust and produce leaks from the port. Also, when the water heater is rusting out, except the anode, other elements such as heat traps (nipples), which were previously tight, could become loose and develop leaks again.

Generally, the anode rod has a lifespan of 5 years; therefore, it is recommended to replace it after that period. The unit should be regularly maintained, especially if the water is hard and due to the sediment buildup.

So, if you notice brown rust in the tap water, the anode rod might be having issues. A leak from the anode rod connection needs expert hands and immediately, or it could cost you the water heater.

Again, it is important to drain your tank every year to prevent sediment buildup. This will also help to extend the lifespan of the anode rod.

Water heater is leaking from the top heating element: Things to do

Electric water heaterElectric water heater
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If your water heater is leaking from the top of the heating element your gasket is worn out or damaged, resulting in dripping leaks. To fix this, you would need to open the cover plate on the side of the tank. Then, move the insulation aside to check for leaks and make easy access to the heating elements.

However, you should note that it's not always easy to spot the leak from the heating elements as they are insulated. Also, they are covered by an access panel. So, you might need expert help with this. The gaskets (washers) that seal the water may no longer be watertight, which means they'll need to be replaced.

To remove the heating element and replace the gasket, you have to turn the power off (on the main circuit breaker), drain the tank, and disconnect the wires from the terminals. It is also important to clean the contact surfaces thoroughly.

Then, you will need a socket or element wrench to unscrew the element and a new gasket to replace the damaged one. You can find the gasket (washer) at the big box and hardware stores cheap.

Water heater is leaking from the top seam

Again, it is possible to have a leak from the seam at the top of the tank. This is a sign that your tank needs to be replaced as it developed some cracks. The main causes are corrosion, damages, or deformation due to high pressure. For this, you're going to need the services of a professional. Any structural damage would require you to buy a new water heater.

Water is leaking from the vents

Another place where your water heater might be leaking is from the vent, especially during the heavy rain and high winds.

It is also normal to see some condensation, especially on the high efficient water heaters.

Leaking from the plumbing pipes

Importantly, your water heater could be leaking from the pipes. Actually, this is probably the first place to check once there's a leak. A drip from the plumbing pipes above can find its way down, making it seem like the tank is leaking.

Check the plumbing pipes above the heater. Pay attention to the heater's water supply lines, which may be rigid or flexible tubes.

Sadly, flexible tubes are most often the cause of water heater leaks. This is because they fail long before your water heater needs replacement. Remove any insulation on the supply lines above the heater to inspect properly, replace afterward.


Sometimes, you may suspect that the water heater is leaking, but you can't seem to find any leaks. If that happens, use a piece of cloth to clean the standing water, then examine the plumbing elements and surrounding pipes. If the water puddle does not gather again, then it is condensation that caused it.

Condensation is very common with water heaters and their surrounding parts. Over time, they leave small puddles of water on your basement floor. And if the unit can't meet up with the hot water demand of your household, there's even more condensation. The moisture on the tank doesn't dissipate because the tank isn't big enough.

As such, it is important always correctly to size a new water heater before buying one.

What to do when your water heater is leaking from the top

Turn off the supply of cold water to the tank. First, turning off the cold water supply to the tank is essential using the cold water shut-off valve. You can find it just above the water heater. Be careful during this process because if there's a major leak, it can cause flooding and damages. If, due to flooding, you cannot access the valve, just turn off the main shut-off valve.

Turn off power. Next, turn off the power supply as well to keep it safe. This is an essential precautionary measure that can prevent an accident. There are different ways to turn off the power supply for different kinds of water heaters.

Turning off the power supply of an electric heater. For an electric heater, find the circuit breaker box of your home. Then look for the electric breaker and turn it off.

Turning off a gas water heater. With a gas water heater, turn off the gas supply using the dedicated gas shut-off valve. You can find that on the gas line leading to the tank.

Find what's causing the leak. Again, several things could make a water heater leak from the top. It could be the TPR valve, a corroded anode, condensation, or bad plumbing work, among others. Check carefully to discover the source of the leak.

Repair or replace what is causing the leak. Now that you know the cause of the leak, it's important to repair it as soon as possible if it is fixable. If you can DIY, that's fine; if not, get an expert to handle the repairs. This might also be an excellent time to replace any worn-out parts.

Start your water heater again. Finally, turn on the unit once the repairs are done. You can do this by turning on the cold water supply as well as the circuit breaker.

Dangers of a leaking water heater

Let's face it; a leaking water heater can be dangerous and even fatal to your safety. Just like some issues in your home, it could cause you problems ranging from inconveniences, damages, and money for repairs.

As water is heated inside your tank, the pressure builds up. Sometimes, it could get to a dangerously high temperature, and when that happens, your tank should shut off automatically. It could also release pressure through the safety valve (T&P valve). When neither happens, you might witness a rupture and then flooding or even an explosion.

Also, the tank deformation can lead to a fire outbreak and the risk of electrocution. Therefore, it is important to pay quick attention once you suspect a leak.

Finally, after repairing a water heater, it is vital to observe and see if the problem persists. If the leaking continues, you should seek the services of a professional plumber.


According to the experts and per user complaints, most water leaks in water heating systems come from flexible water fittings such as threaded inlet and outlet connections on top of the tank. Also, improper heater installation can make the unit leak prematurely.

The threads might not be adequately taped, or the fittings are loose.

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