Leaking Water Heater

leaking water heater

Call us at (559) 940-0890

Repairing a water heater leak can involve various methods, both easy and difficult. A lot of people conclude to replace a water heater upon noticing the first leaks, but that should not be the case.

There are many easy and cheap fixes instead, and you can extend the useful life of a water heater a number of years by simply replacing a damaged part.

To diagnose the leakage source and identify the right fix, you should look out for the following things.

Inspect the Water Supply Line

First of all, you need to check the plumbing pipes on top of the water heater. A drip coming from above can easily be noticed even on the water heater tank itself as it drips down.

Use a stepladder, if needed, to inspect the pipes at the top of the water heater. Observe the supply line feeding the water heater especially, which can either be flexible tubes or stiff pipes.

Flexible tubes are the most popular reasons for leaks at the top of the water heater as they are known to get damaged long before the heater is due for replacement.

To replace the flexible line of the water heater, first, turn off the gas or electricity supply to shutdown the heater.

Instructions to shut the gas valve can normally be found on the front of the tank on gas heaters. Electric heaters can be disconnected at the switch or a dedicated breaker.

Next, turn off the water supply into the water heater. Do this by turning the shutoff valve on the cold line into the heater.

Before taking out the supply tubes, confirm that no water is supplied to the heater by opening a faucet hot side anywhere in the house.

No water should come from this if the supply had been correctly turned off.

Check the Nipples of the Water Heater

The nipples connect the heater to the cold water supply pipe and the hot water outlet pipe, and are also very likely to leak. The water heater nipple threads are very thin and usually leak from time to time.

It may not be easy to differentiate this leak from that of the flex supply tube, but if the latter has been replaced and the leak persists, then the nipple is the likely culprit.

It can be quite challenging to remove the water heater nipples and you will need some leverage and a pipe wrench.

Ensure the water is actually shutoff before handling this repair. Most times, this job requires a professional.


Some states require you to have a dielectric union fitting if copper pipes are used to directly connect to the nipples of galvanized steel.

Corrosion occurring from contact of copper and galvanized steel is prevented by the dielectric union which creates a slight electric charge.

Inspect the Temperature & Pressure (T&P) Release Valve

The T&P valve is another possible source of leaks which can be even more severe. A leak on the T&P valve typically indicates a bigger problem.

If you recently replaced the valve, it could be that it is not properly sealed. You may be able to solve the problem by tightening or reinstalling it by wrapping new plumber’s tape around the threads.

If there is excessive heating of water in the heater, the pressure might weigh on the T&P valve. For this, you can reduce the temperature or install an expansion tank where there is none already.

A leaking T&P valve may be an indication of a generally high water pressure in your home, and a faulty pressure regulator.

If your home’s water pressure and your water heater appear to be working normally, then your T&P valve may be faulty and require replacement.

Before doing this, ensure to properly turn off the water and release pressure from the tank by opening the T&P valve lever or a hot water faucet anywhere in your house.

If you still cannot resolve the issue, then you should get a qualified plumber to help correct the situation.


Never forget that you are working with extremely hot and pressurized water, so you should take adequate precautions.

We highly recommend getting a professional for these leak repairs since a lot of things can go wrong. Certified experts should always be responsible for fixing gas appliances.

Inspect the Drain Line

Another popular issue is leaks in the drain valve below the water heater. It is not unusual for drain valves to not fully close after a water heater has been flushed or drained.

You can use a hose cap on the drain valve, or even replace it completely. Shut off the heater properly and drain it out before you remove and replace this valve.

Check the Tank

Lastly, if you cannot find the culprit after all of these previous checks, then you may have a damaged tank within the water heater.

This would normally be a severe, flooding leak, not light dripping. Ruptured and leaking tanks cannot be fixed, as the water heater must be replaced completely.

Call us at (559) 940-0890

Clovis Plumbing Services
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