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How To Turn On Water Heater? [Gas, Electric, Tankless Water Heaters Covered in 2023]

how to turn on water heater

The installation professional may turn on hot water heater for one time after the installation is complete. But what to do when you are out for a vacation?

The safest thing to do would be to turn off the heater. But, turning it off without even knowing how to turn it back on can be very confusing. There are multiple variations of water heaters available in the market today including the gas, electric, and tankless heaters.

However, if you do have the right guide, it’s not going to be a difficult task in hand to turn it on. You may have to turn them off and on every time after you have cleaned the heater or completed flushing the unit. So, let’s begin the guide on how to turn on water heater.

How to Turn On Gas Water Heater?

Step 1: Close the valves

To kick start the process, the first thing that you need to do is to check all the valves and the faucets. If you turn on the power leaving the faucets on, it will build pressure within the heater causing it to damage.

If they are turned on, you will be able to hear a whistling sound inside the heater. So it’s best to close the valves and the faucets before turning on. Make sure that there are no gas leaks present as a part of precaution. If there is, contact a professional.

Step 2: Release the Coldwater

The next step is to turn on the cold water supply into the heater. Since the tank is empty, it will require water to heat. Turning on the cold water supply will release the water from the faucet directly into the tank.

Once it is turned on, you need to wait for a few minutes before it gets a refill. You must allow the heater tank to be full before you turn it on.

Step 3: Pilot Light

The next step that you need to go through is to turn on the pilot light. For this, you need to provide power to the heater. Fulfill the necessary steps and then you need to go to the reverse side of the heater.

Here, you will find the control of the pilot light that sets out the ignition. Turn it on so that the heater can be prepared for burning. But be very careful while doing so. Try to avoid direct hand contact and wear gloves if possible.

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Step 4: The Gas Valve

If you are done with all the three steps above, you are only left with one more. It is to turn on the gas valve. The gas valve is usually located at the bottom of the heater and comes with a small knob.

If you are not sure which way to turn to release the gas, grab the manual, and then follow the instruction. The direction for turning on the valve may be different for different brands. So you need to be sure before turning it on.

How to Turn On Electric Water Heater?


Step 1: Check the valves

Just like the concept of what you did with the gas water heater, you need to do the same here. Look for all the facets that are connected with the heater. If you find any of them to be turned one, simply close them.

Apart from this, you also have to check for the valves present just around the heater. If you leave them open, air pressure will increase inside the tank causing the interior components to fail. So make sure that you have turned them off.

Step 2: Allow Cold Water to Flow

The next thing that you need to do is to release the cold water faucet. Before you power the heater, you will always want it to be filled with water. Low water quantity inside the heater means that the same air bubbles will form.

This will not allow the water to be properly heater and perform accordingly. So gently open the valve and the faucet to let the cold water flow into the tank. Wait for some time till the tank is filled with water.

Step 3: Safety Tag

Electric water heaters come with a safety tag that we use while turning off the heater. It prevents anyone to turn on the heater accidentally while not using the device. So you need to carefully bring out the safety tag before the power is turned on.

One more thing that you need to consider is to have a complete dry hand and wear gloves if possible. Make sure that you take protection from electric shocks.

Step 4: Circuit Breaker

The circuit breaker is another important part of the electric heaters that we use. It is the power source that allows the power adaptor to get connected with the main working unit. If you are node with the other steps, now it is the time to turn on the heater.

Connect the circuit breaker and turn it on. This will allow the heater to be ready for work. If you do not have a circuit breaker, you must hear low noises that will indicate the heater is ready to start.

How to Turn Tankless Water Heater On?

The procedure to start a tankless heater is completely different from the rest. Since all of the models are based out of electrical ignition, it’s quite similar to start but not the same.

Since they are tankless, you won’t have to waste your time while waiting for the heater to fill up. The best part is that these heaters can start instantly. You can follow the steps below to know more.

Step 1: Circuit Breaker

The first thing that you need to do is to safely power the device. But before this, make sure that you have connected the circuit breaker with the product. It allows the heater to utilize the power and provide ignition to the product.

Step 2: Confirm Temperature

The next thing that you need to do is to pick up a suitable temperature. You can do this with the help of an adjustable thermostat present just above the heater. Usually, there is also a remote that may be present with the package.

Some of the manufacturers allow the settings to be changed with the remote. By default, the temperature is set at 140 degrees Fahrenheit. You can easily change the dial accordingly.

What Precautions Do I Need to Follow?

  1. The first thing that you need to do is to check the pressure available through the discharge pipe. If there are drips, the pressure is too high. Usually, it should be anything below 80 PSI.
  2. When you turn on the water heater, make sure that no one has used it just a few minutes back. This is mainly because all the gas valves may still be too hot to touch and there may also be some chances for leakage.
  3. Always take a thorough look at the bare wires or the cutters present inside the heater. If you find such a situation, immediately repair it without turning on water heater.
  4. The next thing that you must do is to have a diagnosis on the T and P valve. It is one of the most important components of the water heater. Make sure that this valve is always working correctly.
  5. When you have just turned on the gas valve, try to keep a distance from it for a while. The gas may be unstable and it may have minute leaks. It is not very safe to inhale the gas directly.

Final Talk

Whether you are in your home or a commercial place, regularly turning it on and off should be a common habit. It keeps a heater healthy and safe to use. But if you are facing any technical difficulties while turning on hot water heater, you can run a quick diagnosis check.

Look for the error code on the display and then contact a professional. If the heater turns on perfectly it means that all the sensors and the valves are working fine.

Do let us know down in the comments below about the recent experiences on how to turn on water heater. If you are facing problems, do let us know about it also.

Jimmy J. Walker