Who to call for a leaking water heater, and what to do first

One warning comes first. If you smell gas or hear a blowing or hissing noise, don't stop to look at the heater. Open a window and get everyone out quickly. Then, from a safe distance or a neighbor's home, call 911 and your gas company^1,2.

If there is no gas smell, call a plumber. Rheem, which makes water heaters, says that if your water heater is leaking, you should call a plumber as soon as possible to have it inspected and, if needed, replaced³. Looking after a gas water heater is the owner's job: Atmos Energy, a gas utility, tells its customers that routine safety inspection and maintenance of their gas appliances are the customer's responsibility⁴.

Below: what to do while you wait, what to tell the pro, what a written quote should list, and where a permit comes in. Every line comes from a water heater maker, a gas utility, a university extension or a government page.

What to do first

These steps are for a leak with no gas smell. A. O. Smith, which makes water heaters, says to turn off the power or gas to the heater before any inspection⁵.

Turn the heat off. For an electric water heater, switch off its breaker at your home's electric panel. For a gas water heater, if you are confident doing it, find the gas shut-off valve near the heater and turn it to the off position.⁵
Turn the water off. Close the shut-off valve on the cold water line that leads to the heater, so the leak does not get worse.⁵
Put a bucket under the leak. Take care: the water may be hot.⁶
See where the water comes from. Water at the side often comes from the T&P (temperature and pressure) relief valve. Water at the base of the heater is often the first sign of a serious problem.^5,5,7
Take photos of any visible leaks, rust or unusual condensation around the tank, to show the plumber.⁸

Who should not do this: Anyone who smells gas or hears a blowing or hissing noise. Skip every step. Get everyone out, then call 911 and your gas company from a safe distance.^1,2

Who should not do this: Anyone who is not confident turning the gas valve. A. O. Smith says to turn it off only if you are confident doing so.⁵

When it's a job for a pro

The tank itself is leaking. A. O. Smith says a tank that is confirmed to have a leak should be replaced.⁹
The relief valve drips every time the heater heats up. Bradford White, another maker, says that happens where a valve on the incoming water line does not let water flow back. It names two fixes: a valve with a back flow by-pass built in, or a properly sized thermal expansion tank.⁷
You turned the gas off at the main valve outside. Ready.gov says only a qualified professional can turn it back on, and never to try it yourself.¹
The heater's breaker keeps tripping. NC State Extension's home guide says a breaker that trips often is a job for an electrician, who can find the cause and make the repair.¹⁰
The job needs a new 240-volt circuit. Rheem, writing about heat pump water heaters, says that work must be handled by a licensed electrician.¹¹

What to tell the pro

Rheem says to give the plumber the brand, model, age and any warranty details, and to photograph any visible leaks, rust or unusual condensation around the tank.⁸
A. O. Smith says the nameplate on the side of the heater lists the tank capacity and the model and serial number. On an electric heater it also lists the wattage and voltage of the heating elements.¹²
Bradford White says to read the rating plate to find the model number and serial number. On its heaters, the first two characters of the serial number stand for the year and month the heater was made.¹³
A. O. Smith says the easiest way to spot a gas water heater is the metal vent pipe coming out of the top. It says gas and electric systems have different installation requirements, which affect both the timeline and the cost.¹⁴

What a written quote should list

The Federal Trade Commission (FTC) says a written estimate should describe the work, the materials, the completion date and the price. It says to get more than one estimate, and to ask why if the estimates are far apart.¹⁵
The FTC says that before you sign a contract, you should make sure it includes the contractor's name, address, phone number and license number.¹⁵
The FTC says to check with your state or county government to confirm a contractor's license, and to ask the contractor for proof of insurance.¹⁵
In Texas, the State Board of Plumbing Examiners says a plumber's written estimate and invoice should show the Responsible Master Plumber's license number.¹⁶
Ask whether the quote covers a thermal expansion tank. A. O. Smith says a check valve or pressure-reducing valve on the cold-water line makes a closed system, and that its warranty is void for a heater installed on a closed system without a correctly sized thermal expansion tank.¹⁷

Permits depend on where you live

Texas law requires every city with more than 5,000 people to require a permit before plumbing work. The exceptions are repairing leaks or replacing a bathroom-sink or kitchen faucet, a ballcock (the valve that refills a toilet tank) or water control valve, a garbage disposal, or a toilet. A water heater is not on that list.¹⁸
The City of Minneapolis, Minnesota, says you need a plumbing permit to replace or install a water heater.¹⁹
The City of Phoenix, Arizona, lists water heater replacements completed by a licensed contractor among home projects that do not need a permit. A do-it-yourself electric water heater replacement is on its list of projects that do need one.²⁰

Published by CrewButton (Econ Labs, LLC, Addison, Texas). Drafted with AI (Claude) from the sources below. Facts were checked against their sources by AI, and the page was approved by CrewButton's founder on November 12, 2026. First published November 12, 2026. Updated November 12, 2026. Last reviewed November 12, 2026.