How to Turn Your Water Heater On and Off

Familiarize yourself with the layout of the water heater and, if you have the manual, read the section on how to turn off the hot water.

Turn Off the Controller

If you have a standard gas water heater with a gas control unit at the bottom, turn the control knob to the "off" position. If your heater has a touch screen display and user interface module (UIM), disable the water heater using the "enable/disable" switch. Turn off the electrical supply to the water heater.

Turn Off the Gas Supply Line to the Heater

Find the gas supply shut-off valve. It's usually located within a few feet of the heater near the gas burner. Close the valve by turning the handle so it’s at a right angle to the gas line.

Run Hot Water Through a Faucet

Run hot water through a nearby faucet for at least 10 minutes to cool the water in the tank.

Turn On a Hot Water Faucet in Your Home

Open a nearby hot water faucet to help the hot water tank drain quickly.

Open the Drain Valve

Drain the tank by opening the drain valve. You may need a screwdriver to turn the valve.

Check the Anode Rod and Flush the Tank

After you've drained the hot water tank, take the opportunity to check the anode rod. It's usually mounted on top of the water heater under a plastic cap. You'll need a large socket or box spanner to remove the anode, often a 1 and 1/16-inch socket. Replace the anode if it's in poor condition, or if you can see the 1/8-inch steel core wire.



If there's a lot of sediment, flush the tank by opening the cold water inlet valve while the garden hose is connected to the drain. Flush until the water runs clear.

Lighting the Burner for a Gas Water Heater With a Standard Gas Control Valve

Follow this procedure for water heaters equipped with the standard (Honeywell) gas control valve.

Set the Gas Control Valve for Startup

Turn the gas control knob on the controller to the pilot position.

Light the Pilot

Press in the gas control knob fully. Click the igniter button below the knob repeatedly for up to 90 seconds until you see the status light flashing. Once the light is flashing, release the gas control knob. If the status control light doesn't start flashing after 90 seconds, stop and wait for 10 minutes before trying again. You can repeat this procedure three times.

Check the Status Light

The status light should flash every 3 seconds. If it stays on but not flashing, the pilot has gone out and you must light the pilot again as described above.

Gas water heaters with a touch display and UIM controller have an automatic startup cycle.

Enable Gas Purging

Set the "enable/disable" switch to "enable" and set the temperature to the lowest setting. Switch the "enable/disable" switch to "disable" and wait 5 minutes. Don't proceed if you smell gas; call for assistance according to the safety instructions attached to the water heater.

Start the Water Heater

Switch the "enable/disable" switch to "enable." Set the water temperature to your preferred setting. The water heater will start automatically and heat the water to the set temperature.