Why Is My Water Heater Leaking? Common Causes & How to Fix It – 2026

Common Reasons for a Leaky Water Heater:

• Cracked or Corroded Tank: Over time, internal sediment causes the metal to weaken. This eventually leads to a leaking hot water tank that cannot be repaired and requires a full replacement.
• Loose Fittings and Pipe Connections: If the connections around the top are loose, you’ll notice a leaky hot water heater dripping down the sides of the jacket.
• Pressure Relief Valve Issues: If the PRV isn’t installed correctly or fails, it may result in a hot water tank leak or constant water discharge.
• Worn Out Anode Rod: This rod protects your tank from rusting. Once it’s gone, the tank begins to corrode, leading to a leaky water heater within months.

Identifying the Source of the Leak

The first step in repairing a hot water tank is identifying where the water is coming from. You need to determine if the water heater is leaking from the bottom or the top. The leak could be coming from a faulty valve, a loose supply line connection, or the discharge pipe itself.

To find the source, use a bright light to inspect the area thoroughly. If you have an HVAC unit nearby, check around it as well, as condensation could be mistaken for a hot water heater leaking. Taking the time to pinpoint the exact location will help you decide if you need a simple part replacement or a whole new unit.

Safety First

Before repairing a hot water tank, always de-energize the system:

• Turn off the electricity at the main breaker panel.
• Shut off the gas valve if you have a gas-powered unit.
• Close the water supply line to stop additional water from entering the tank.

Taking these precautions ensures a safe and controlled repair process.

Inspecting the Top of the Tank

Start by inspecting the top of the tank where the inlet and outlet lines are connected. Pay close attention to the joints and couplings, as these are common areas for hot water tank leaks. If you notice any water around these joints or spill water near them, it’s a clear sign that the water heater is leaking .

Also, check the anode rod inside the tank. While a rusted or corroded anode rod won’t directly cause a leak, it can contribute to corrosion inside the tank, which could eventually lead to leaks over time. Replacing a worn-out anode rod can help extend the life of your water heater and prevent future. Anode rod can be found in top as well as bottom on side of tank.

Fixing the Leak from Top of Hot Water Heater:

• If the leak is coming from a threaded joint, try tightening it slightly. Be careful not to overtighten, as this could cause damage to the threads.
• In some cases, open the joint completely, clean it, and then reattach it using pipe dope and plumber’s tape to ensure a tighter seal. Only do this if you have the proper tools and feel confident in your ability to do it safely.
• If Leaking for Anode Rod, With the water and electricity off, unscrew the rod’s hex head, which is situated on the top of the tank, using a 1/16-inch socket. Remove the rod from the tank. Replace it with a new one, readily available at most hardware and home improvement stores, if it has shrunk to 12″ or less in diameter. Teflon tape should cover the thread before securing the replacement rod with screws.

If the joint is soldered and it’s leaking, it’s best to call a professional plumber to repair it, as soldered joints require specialized skills and tools to fix properly.

Inspecting the Side and the Pressure Relief Valve (PRV)

Inspect the side of the water heater for any visible issues. One common feature you’ll find is the pressure relief valve, which helps prevent pressure buildup in the tank by releasing water if the pressure gets too high. This is a normal function, and we’ll cover it in more detail in the next step.

While inspecting the side, also check for any bends or cracks in the tank. If you find a crack or bend that’s causing the hot water tank leaks, the only permanent solution is to replace the tank. However, for temporary relief, you can use strong water seal tape to stop the leak. Just make sure that the tape you’re using can handle the high temperatures of the tank to avoid further issues

Inspect the Pressure Relief Valve (PRV):

The pressure relief valve (PRV) is a major component of your water heater. Its function is to release water if the pressure inside the tank exceeds safe levels.  This is usually on side in top section of hot water tank. If your PRV is dumping water, it could be due to excessive pressure or temperature.

Fixing the Issue:

• First, check the temperature setting on your water heater. Ensure it’s set to the recommended 120-140 degrees Fahrenheit. If the temperature is too high, it could cause the PRV to release water.
• If the temperature is properly set and the PRV is still leaking, there’s no need to replace the tank. In this case, you can replace the PRV itself. It’s a relatively simple fix, but if you’re not comfortable doing it yourself, it’s best to call a reliable plumber to have it replaced professionally.

Water Heater Leaking from the Bottom

The water heater leaking from the bottom is the most common complaint we hear at Everest Drain & Plumbing. At the base of the tank, you’ll find the drain valve. If you notice moisture here, the valve might not be closed properly or the internal seal has failed.

Fixing the Bottom Leak:

• First, close the valve properly and tighten it slightly—be careful not to overtighten, as that could cause damage. After tightening, check if the leak stops.
• If tightening doesn’t solve the problem, it could mean that the threads on the valve are damaged. In this case, the drain valve will need to be replaced.
• Replacing a drain valve can be a tricky job, and if you don’t have the right tools, it’s highly recommended to call a local plumber to ensure the job is done properly.

Note: If the water is coming from underneath the tank and not the valve, the internal liner is likely cracked. In this case, hot water heater leaking from the bottom usually means the tank has reached the end of its life.

Not Sure of the Source?

If you can’t find a clear source for the leak, it could be condensation causing water to gather around the hot water tank. This is especially common if you have installed water heater is in a cold room.

To test for condensation, wipe up any water around the floor and the hot water heater. Wait a while and check again. If you notice water droplets forming on the tank, pipes, or surrounding areas, it’s likely condensation.

What to do if condensation is causing the leak:

• Relocate the water heater to a room or area with a more stable, warmer temperature.
• Another option is to add insulation around the pipes and the tank to help prevent condensation from forming. This will reduce the chance of a leaky hot water tank caused by temperature differences.

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Call Everest Drain & Plumbing for Expert Repair!

Don’t let a leaky hot water tank cause damage to your home! Whether you need fast leak detection, professional repairs, or a full water heater replacement, our expert plumbers at Everest Drain & Plumbing are here to help.

• 24/7 Emergency Service – We’re available anytime to fix urgent leaks.
• Fast & Reliable Repairs – Get your hot water back quickly!
• Water Heater Replacement – Upgrade to a new, energy-efficient unit.
• Licensed & Insured Experts – Trusted service across Toronto & the GTA.

📞 Call us now at 416-383-7378 or book an appointment online! 💧