How To Turn On Your Water Heater (6 Step Guide)

Last Updated On January 11, 2023
How To Turn On Your Water Heater (6 Step Guide)

Do you need to turn on your hot water heater and aren’t sure how? You don’t need extensive plumbing knowledge to get the task done. All you need to know is your water heater type and follow these simple instructions.

In this PlumbingNav guide, we will teach you:

  • How to turn on an electric water heater
  • How to turn on a gas water heater
  • How to turn on a tankless water heater 

What's In This Guide?

      How To Turn On An Electric Water Heater (6-Step Guide)

      Electric water heaters offer a convenient and safe option for heating the water in your home. Follow these steps to turn on an electric water heater

      Note: For these steps, we will assume that the tank contains no water. 

      Step One: Learn Basic Components of an Electric Water Heater 

      Before you get started, familiarize yourself with your water heater. You especially need to know how to locate the electrical supply, cold water valve, and drain valve. 

      Step Two: Open Hot Water Faucet

      Opening the faucets gives the unit access to air. This prevents an airlock, so you may open the faucets when performing maintenance on the hot water heater or when you turn it off for an extended period.

      Step Three: Fill Tank With Water

      Open the cold water valve to allow water back into your electric water heater tank and fill it up. You want the tank completely full before you turn on the power to avoid damaging the heating elements. You will know that you filled the water tank when water runs through the faucets at full strength. 

      Step Four: Turn Hot Water Faucet Off

      At this time, you should close the hot water faucets you opened when filling the tank. Now that you filled the tank with water, you no longer need the airflow or ability to see the water pressure. 

      Step Five: Provide Power to Water Heater

      Your water heater plugs into a wall outlet with a power cord. Before you start, verify you properly connected the power supply to the electrical socket. Otherwise, you won’t get any power to the unit, and your water will remain cold.

      Now, you can reactivate the power. Open your circuit breaker box and find the circuit that controls the power to the water heater. Ideally, you clearly labeled all of the different circuits to make it easy to identify. 

      Next, you need to verify your water heater actually has power. If your water heater has lights or a digital display, the lights indicate power. If you hear noise, this can also indicate power. 

      Step Six: Check For Hot Water

      It takes time for an electric water heater to heat the water in the tank, depending on the size of the tank and the first hour rating (FHR) of your water heater. 

      Electric water heaters tend to take the longest amount of time to heat the water in the tank. However, if after 2 – 3 hours you don’t have hot water, troubleshoot your water heater. Some of the common reasons an electric water heater doesn’t get hot water include:

      • No power
      • Power surge
      • Cut-off switch activated
      • Defective heating elements or thermostat
      • Tank not full due to leak or open drain valve

      To perform troubleshooting, you will diagnose the source of the problem and take the proper steps to resolve the issue. One common troubleshooting method requires you to reset your electric water heater. See the instructional video below to learn how!

      How to Turn on a Gas Water Heater (6-Step Guide)

      You have multiple options when it comes to gas water heaters, including condensing and non-condensing, as well as direct vent and power vent. Despite the type of gas water heater, they all turn on in a very similar way. 

      Follow these steps to turn on a gas water heater. We will assume that the tank contains no water. 

      Step One: Learn Basic Components of a Gas Water Heater

      Despite the multiple types of different gas water heaters, all tank-type water heaters have the same basic components. You want to especially take note of the location of the cold water valve, on/ff pilot, and gas supply. 

      Step Two: Confirm Hot Water Faucets Off

      If you performed maintenance or repairs on your water heater, you likely turned on one of the faucets in your home to allow airflow into the unit. Turn the faucet off to prevent draining the water from your tank. 

      Step Three: Open Cold Water Valve To Fill Tank

      Now, you need to activate the cold water valve to refill the tank. In most cases, you will find the cold water valve on the top of the unit. You may want to open a hot water faucet so you can know when you filled the tank. After you fill the tank, the water will pour at top pressure. 

      Step Four: Light Pilot Light 

      The pilot light in your hot water heater ignites the burner with a small gas flame. First, you need to find the pilot and its controls. Units vary in this setup.

      A gas valve will provide three options: “ON”, “OFF”, and “PILOT”. At this time, you need to turn the knob to “PILOT.” Depending on your model, you will press the red pilot button or light the actual pilot with a match. This provides a flow of gas that will ignite the pilot light. 

      Once you see the flame, hold down the pilot button for an additional 30 – 60 seconds before releasing it. 

      Step Five: Turn Gas Knob to “On”

      With the pilot light on, turn the gas knob to “ON.” The pilot light should stay lit and ignite the burner, allowing the device to heat your home’s water. 

      Does the pilot go out every time you try to light it? Determine the reasoning and fix the problem. 

      Some common reasons a hot water heater pilot light will continue to blow out include:

      Step Six: Verify Hot Water

      The time required to heat the water in the water heater tank depends on a number of factors, but most homes see hot water in about 2 – 3 hours after turning the device on. 

      Gas water heaters tend to heat water faster than electric water heaters due to the direct heat source in the form of the pilot. 

      If the water doesn’t feel hot, verify that you can still see the pilot light flame. If you don’t see a pilot light, take the proper troubleshooting steps, including cleaning the thermocouple and eliminating excess airflow. 

      did you know how to turn on hot water heater

      How to Turn on a Tankless Water Heater (4-Step Guide)

      Tankless water heaters save space, and they work much more efficiently than tank-style water heaters. Most models also keep things user-friendly. 

      Both gas and electric tankless water heaters use electricity in the ignition process, so the process remains essentially the same for both types. 

      Follow these steps to turn on a tankless water heater:

      Step One: Learn Your Tankless Water Heater Control Panel

      In almost all cases your tankless water heater will come with a control panel for easy use. While control panels vary by model, most control panels have a display that shows the temperature, a power button, and temperature control buttons. Some models will also have a button for mode selection and different indicator lights. 

      Step Two: Turn Power On At Circuit Breaker

      Both gas and electric tankless water heaters use electricity to start the unit. For this reason, you need to go to the circuit breaker and turn on the power to the hot water heater. 

      First, ensure the unit has a connection to the electrical outlet nearest to it. You will know the device has power when you see the control panel light up. 

      Step Three: Press Power Button On Control Panel 

      Next, you will simply hit the power button on the control panel. In many cases, an indicator light will provide reassurance that you turned the unit on. You may also hear noise coming from the unit.  

      When activated, a gas burner or electric heating element will heat the water as it enters your home, depending on the fuel source for your specific tankless water heater

      Step Four: Verify You Have  Hot Water

      Tankless water heaters provide hot water on demand. This means, unlike tank-style hot water heaters, you should have hot water right away. Check a faucet connected to the water heater to ensure you have hot water. 

      When you use a tankless water heater in your home, you have the option to use one unit for a whole-home hot water solution or use multiple point of use water heaters around your home. 

      If you use multiple point of use water heaters, check the hot water in a faucet heated with the particular water heater you just activated. 

      No hot water coming from your tankless water heater? If you do not have hot water, you will need to troubleshoot the device. 

      Some of the most common reasons a tankless water heater will not produce hot water include:

      • Ignition failure
      • Heating element failure
      • Burner failure
      • Thermostat failure
      • Power surge

      Quick-Read FAQS For Turning On A Water Heater

      Don’t have time to go through all of the details? Find the answer to your questions with these simplified answers to your frequently asked questions. 

      How do I turn on my electric tank-style water heater?

      1. Learn basic components of electric water heaters
      2. Turn on hot water valve
      3. Fill tank
      4. Turn off hot water valve
      5. Provide power to water heater
      6. Verify you have hot water

      How do I turn on my gas tank-style water heater?

      1. Learn basic components of gas water heaters
      2. Fill tank
      3. Close hot water faucet
      4. Light pilot light
      5. Turn the gas knob to “On”
      6. Verify you have hot water

      How do I turn on my tankless water heater?

      1. Learn your tankless water heater control panel
      2. Turn on power at the circuit breaker
      3. Press the power button on the control panel
      4. Verify you have hot water

      How do I know my water heater is on?

      You will know you successfully turned your water heater on when you get hot water. You may also see lights on the control panel on the unit or hear the unit running. 

      How long will it take for me to get hot water after I turn on my water heater?

      If you have a tankless water heater, you should have hot water instantly. If you have a tank-style water heater, you should get hot water within 2 – 3 hours, depending on your water heater. 

      Gas tank-style water heaters tend to heat up water quicker than electric tank-style water heaters, but it depends on the size of the tank and the unit’s First Hour Rating (FHR).

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      About Plumbing Navigator

      We write about "all things plumbing," helping you navigate common questions, repairs, and the best plumbing products on the market.

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      We write about “all things plumbing,” helping you navigate common questions, repairs, and the best plumbing products on the market.

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