Sunrise Specialty » How to Turn on a Water Heater (12 Precautions to Follow)

How to Turn on a Water Heater (12 Precautions to Follow)

There are many types of water heaters in the market right now, and it can get confusing. You may find a tank water heater, tankless water heater, or hybrid water heater in your new building. Tank water heaters used to be the industry standard and were very popular, but nowadays, tankless water heaters are becoming more preferred for many reasons especially portability.

Point-of-use water heaters are mostly used if the homeowner prefers their hot water delivered quickly to faucets or appliances that are not close to the central heater. Hybrid water heaters are relatively new, and the biggest reason they are being adopted is that they save energy costs.

Now, as the heading suggests, this is not a lesson on which water heater type is best. Regardless of which water heater type you have, we would like to show you how to turn on a water heater in case it’s your first time. We don’t want you running around looking for a professional for everything, including this. You can check out our other helpful articles on water heaters for more guidance.

So How Exactly Do You Turn on Your Water Heater?

The specific steps to turn on your water heater largely depend on the kind of water heater you use.

So, what we’re going to do is explain the guidelines to follow for different types of water heaters. Note that each of these steps is important and should not be skipped or considered insignificant. Ready? Let’s go!

How to Turn On a Gas Water Heater

Follow these steps to turn on your gas water heater:

Step 1: Check For Any Open Valves or Faucets and Close Them

Start off by checking for any valves or faucets that may have been opened, either accidentally or by you while you were working on your tank. Someone might have opened it up to let a little bit of air into your hot water tank. Whenever you’re about to turn the water heater on, the first thing to do is close up the open faucets.

Step 2: Turn the Cold Water on

Turn the Cold Water on

The next thing you should do is turn the cold-water supply on. You’re doing this so that your tank gets a refill. It is crucial because the last thing you want to do is turn your heater on with a tank that isn’t full.

Step 3: Light Your Pilot Light

Light Your Pilot Light

You must light your water heater pilot light so that your hot shower can get back in business. It’s also important to do this to avoid any accidents from the release of gas.

Step 4: Turn on Your Gas Valve

Turn on Your Gas Valve

If your valve is turned to “pilot”, you won’t have to go through the pilot light step. All you need to do now is to turn on your gas valve.

At this point, the heater should be heating up the water already; the burner should be fired up. If you check this on your heater and it isn’t the case, then you may need to go back to the pilot light stage and follow every step. There will be a link at the end of this article to a step-by-step guide.

How to Turn On an Electric Water Heater

Follow these steps to turn on your electric water heater:

Step 1: Check for Any Open Valves, or Faucets Close Them Up

Just like in the first step for turning on your gas water heater, you also have to check your electric water heater to see if there are any open valves or faucets. Anyone you find ajar should be closed up immediately.

Step 2: Turn the Cold Water On

Turn the Cold Water On 1

Again, make sure that your tank is filled with water before turning the power on. You do not want the heater heating an almost empty tank. This could ruin your tank or even the heater.

Step 3: Take Out the Safety Tag

If you placed a safety tag over your breaker to prevent anyone from turning on the switch, then it’s time to take it out. If the house is not yours, the owner could have placed the tag on the switch, so be sure to check.  If the house is yours, you should learn to do so to prevent shocks from electricity.

Step 4: Turn on the Breaker

Turn on the Breaker

Your water heater breaker is safe and ready to be turned on now.  At this point, the water heater should begin heating the water. Some electric water heaters models may not give off any sign to show the unit is on. However, you should hear low noises that indicate that the heater has gone to work.

How to Turn On a Tankless Water Heater

How to Turn On a Tankless Water Heater

Tankless water heaters are the easiest to turn on. Follow these steps to turn on your tankless water heater:

Step 1: Turn on Breaker

These kinds of water heaters are tankless as the name implies so this means you won’t have to fill it with water like other water heaters as long as it is connected to the water supply. All you need do is simply turn the breaker.

Step 2: Confirm Temperature

You’d have to pick a suitable temperature since the heater works based on your demand. It will heat up depending on the temperature you choose and will start heating up only when you need it.

When turning on your water heater, you have to be careful to avoid accidents. Below are precautions you should keep in mind.

Precautions to Follow When Turning on Your Water heater

  1. Check for drips in your discharge pipe. If you notice any drips, the pressure may be too high, turn it down immediately (below 80 psi is low enough).
  2. When turning on a gas heater that no one has used in a while, watch out for any smell of leaking gas. Gas smells bad for good reason, and if you don’t know how they smell, some people would compare their smells to that of rotten eggs. Do this before you light the pilot. If there is a smell of gasoline, propane, kerosene, or any kind of liquid that is flammable, do not re-light. If you have a more modern heater, it may prevent lighting from happening.
  3. If you have to turn on your water heater because the pilot light failed, then check for the cause of the failure. Do not try to turn the heater back on if you haven’t rectified the issue.
  4. Check if your water heater is safe for re-lighting and if the relief valve works.
  5. If you use an electrical heater, check for bare wires or clutter. If there is, do not go ahead to re-light the heater until you have fixed this properly.
  6. If you notice that your water heater has been tripping off, no matter how many times you replace a fuse or even reset the breaker, then maybe you should try something else. The best thing to do could be to get your water heater serviced. It should be as good as new after that.
  7. When you’re lighting the pilot light or turning on your gas valve, keep a distance from the opening. Your bare body and especially your face should be kept away. If you’re not careful, and delayed lighting occurs as a result of a dirty burner or maybe an out-of-position pilot, you could get burned severely.
  8. Check your burner for dust, rust or dirt, before proceeding to light the pilot. If the burner is covered with dust, rust or dirt, don’t light. You will have to clean up the burner or get it serviced before lighting.
  9. When you’re about to turn on the gas valve, confirm first that the outer covers and inner covers are in place.
  10. If you try to turn on the pilot and the burner does not ignite, don’t try to make further attempts. Clear the gas first. If you have no idea how to do this, search for procedures till you get what you’re looking for. You can also ask an expert to help.
  11. In all of this, don’t forget that the manufacturer left you a manual. If you’re confused about any part, do not hesitate to consult the manufacturer’s manual. As a quick side tip, never dispose of the manuals of any appliance or gadget you buy in case of times like this. If you lost your manufacturer’s manual, don’t worry, there may still be a way out. Get the manufacturer’s name and your heater’s model number and look them up on the internet. You should be able to find some helpful information on their website.
  12. Many water heaters have guidelines glued on them by the manufacturer; those may also be helpful in troubleshooting them.


Whether it’s a new home or a new water heater, there shouldn’t be too much stress to turn it on. With the information in this article, you should be able to turn almost any water heater on without any complications. Was this information helpful? Let us know in the comments below.

2 thoughts on “How to Turn on a Water Heater (12 Precautions to Follow)”

  1. I have to go on business from time to time so I wanted to teach my wife how to turn on the water heater safely. Thank you for this post, it was of great help to me.

    • I let her try it and it didn’t matter, it worked really well. Thank you for the guidance


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