Nicolette Forbes

By: Nicolette Forbes on August 27th, 2022

Print/Save as PDF

How Do Water Heaters Work?

Standard Water Heaters

Do you have a tank-style water heater but want to further understand how it works? Then you’ve come to the right place!

Water heaters can be complex, and understanding how they work can sound like bungee jumping to most homeowners, which is why we’ve created content like this so that you are prepared for anything. It’s important to know how your water heater works so that if something does go wrong with your water heater, you can easily be aware of it and can take the proper steps to address the issue. 

Monkey Wrench Plumbing, Heating & Air has helped thousands of homeowners with their water heater questions, including helping them understand just how their water heater works in their home, and now it’s your turn.

In this article, we will discuss: 

  • What is a tank-style water heater
  • Identify gas and electric water heaters
  • How a tank-style water heater works
  • Warranties on water heaters

By the end of this article, you will not only be able to understand how a water heater works but also what happens when it isn’t working properly so that you too can become experts.


What is a Water Heater?

Tank-style water heaters (also known as traditional water heaters, standard water heaters, or conventional water heaters) are traditional water heaters that are found in most homes and are used to heat the water used in your home. It’s typically a large cylinder that holds between 30 to 100 gallons of water, with the most common size for homes usually holding about 50 gallons of water. They are mostly found in the garage, closet, or outdoors in a shed.

A Rheem tank-style water heater.

There are three types of tank-style water heaters: gas, oil, and electric.


Different Types of Water Heaters


Gas Water Heater

A gas water heater uses a gas-fired burner located at the bottom of the tank to heat the water inside. There are two types of gas heaters: natural gas and propane. They are both similar, with their only real difference being the type of gas that is used.

While anyone can get a gas water heater, they are ideal for families of four or more people, as an electric heater is likely to have trouble keeping up with the hot water demands of a larger family. Gas water heaters can provide much more hot water, which is key for bigger households. You can easily knock out loads of dishes and laundry using only a small amount of water with a gas water heater.


Electric Water Heater

An electric water heater is a tank that heats water with high-voltage electric heating rods that run upwards through the tank. The main drawback of electric water heaters is their slower recovery rate, as it could take several hours for a 50-gallon tank to recover. Additionally, electric units are affected by power outages, meaning you'll be in the dark with no hot water.


Oil Water Heater

Oil-fired water heaters, like traditional electric and gas-powered water heaters, have a tank system where water is stored, so it is always ready to be used when needed. The biggest difference among all three water heaters is that only oil-fired heaters use both oil and electricity for fuel. With an oil-fired heater, a burner creates an oil-plus-water mixture. The mixture is then exposed to an electric spark and ignited to heat the water.


How Does a Water Heater Work?

Water heaters can be complex, and how they work can be another story! Thankfully, how a water heater works can be broken down into a step-by-step process, along with a fun graphic to help.

  1. Cold water is brought into the tank through a dip tube

  2. Then, the cold water is heated with a gas burner which releases hot but toxic air up through a chimney in the middle of the water heater tank

  3. The chimney moves this toxic air outside through your vents, all while heating the metal of the chimney.

  4. As this chimney heats up, the surrounding water inside the tank is heated as well.

  5. The newly warm water rises to the top of the water heater tank and is moved throughout the home through the heat-out pipe. 

  6. As you open the faucet for hot water, cool water is brought in through the dip tube, displacing the hot water and pushing it through to the faucets and fixtures in your home. 

A diagram showing the parts of the inside of a gas-powered tank-style water heater to better show how a water heater works.

Pro Tip: You can set the temperature you would like your water to be heated to with the thermostat, which can be found connected to the gas line.

Now that you know how a tank-style water heater works, you must be wondering, “do gas and electric work the same?” The short answer is no.

With an electric water heater, the process of heating water goes like this:

  1. The water heater brings cold water in through the dip tube and heats it using the electric heating elements inside of the tank. 

  2. The hot water then rises in the tank and is moved throughout the home through the heat-out pipe.

  3. Lastly, the water, which is now hot, exits the tank and into your home through your fixtures.

A diagram showing the parts of the inside of an electric-powered tank-style water heater to better show how a water heater works.

The main difference between a gas-powered water heater and an electric-powered water heater is that the water is heated by electric elements instead of gas.


Closing Out How Water Heaters Work

Learning how a water heater works sounds like a scary task, but with a little help from some visual representation and a to-the-point bulleted list, it is as easy as turning on your car. Literally. Simply turning on the fixtures in your home will give you the hot water you desire with a tank-style water heater.

Continue your water heater knowledge by clicking on the links below as we dive into how long a tank-style water heater lasts as different factors affect its lifespan and signs it’s time to replace your water heater as the signs usually start when your water is NOT working properly.

How Long Do Tank-Style Water Heaters Last?

5 Signs It’s Time to Replace Your Water Heater

We here at Monkey Wrench Plumbing, Heating & Air are dedicated to giving you all the information you need on water heaters so that you can make the best decision for you and your home. 

If you live in the Los Angeles area and are interested in finding out if a tank-style water heater is right for you, hit the “Book” button below or visit our water heater service page. Or if you have any other questions regarding your tank-style water heater needs, feel free to call us at 310-853-8690, and one of our call center representatives would be happy to help you.