What to Do When Your Hot Water Heater Leaks

Water heaters, whether gas or electric, will last about 10 to 12 years if you take good care of them.

Even so, there’s always a chance your water heater could leak. Often, small water heater leaks can be patched up pretty easily.

There are several things you can do before you call a professional plumber, like Cass Plumbing.

What to Do When Your Hot Water Heater Leaks


The leading causes of water heater leaks include:

Broken drain valves: These will cause water leaks from the bottom of the tank. They’re easily fixed by replacing the broken drain valve.

Corrosion: Sediment buildup can cause corrosion, cracking, and holes in the bottom of the tank. When this happens, it’s usually time for water heater replacement.

Loose water line connections: Normal wear and tear can loosen the inlet or outlet water lines, causing leaks. This problem can usually be fixed by tightening or replacing the loose, worn water lines.

Broken temperature/pressure valves: As their name suggests, these valves monitor and regulate the temperature and pressure inside water heaters. When they break, they can cause water leaks from the sides of a water heater tank.

Of course, various other things can cause water heater leaks—and, sometimes, these leaks are the result of multiple issues. The best way to determine what’s causing your water heater leak and get the best solution for fixing it is by contacting a professional, like the trusted plumbers at Cass Plumbing.


If your water heater is leaking, take these three steps:

  1. Cut the power: This is the very first thing you should do when you find a hot water leak. To turn off the energy source leading to:
    Gas water heater: Find your thermostat. You should see a little knob with three settings: ON, OFF, and PILOT. Switch it to OFF or PILOT to shut off the gas and make the heater safe to work on.
    Electric water heater: Go to your breaker panel and find the breaker labeled “water heater.” Turn it off to cut the power to your unit.
  2. Shut off the water: Turn off the water by finding the cold water line leading to your water heater. There should be a valve on the line; turn it to the right until it closes. This will cut off the water and allow you to move on to the next step.
  3. Drain the water tank: If you have a tank (standard) water heater, draining your water heater is the most essential step. It also happens to be the most involved! To drain your water heater tank:
    Find the drain valve near the bottom of your water heater and attach a garden hose to it.
    Run the hose to a floor drain or sump pit.

With the hose in place, open the valve (on older hot water heaters, this may look like an ordinary spigot; on newer systems, there’s a drain stem with a slot for a screwdriver).

NOTE: Once you open the drain valve, you may notice the water either doesn’t flow or doesn’t flow very well. This is because there’s a vacuum in the water heater.

To break the vacuum, open any hot water faucet in your home. This will let air into the water tank and allow it to drain more easily. Once you establish a good flow, the whole tank should drain in about an hour.

Once the water heater is drained, contact Cass Plumbing at 813-265-9200 for water heating repair service! We’ll find the location of the water heater leak and take care of it quickly.

W offer 24-hour emergency water heater service in the Greater Tampa Bay Area.


The BBB A+ Rated, expert plumbers at Cass Plumbing can diagnose and repair any type of water heater leak or plumbing problem. Whether you have a gas or electric system, or a tank or tankless water heater, we’re ready to provide the highest-quality service to restore your water heater and your reliable access to hot water!