How Does a Tankless Water Heater Work?

Tankless water heaters have become popular for homeowners seeking an energy-efficient way to heat water. But exactly how does a tankless water heater work? If you’ve been wondering whether a tankless system may be right for you, this guide will provide insights and answer that question to help you decide.

What Is a Tankless Water Heater?

A tankless water heater, also known as an instantaneous or “on-demand” water heater, delivers hot water as needed without storing it in a bulky tank. Traditional water heaters continuously heat and reheat a large amount of water. Meanwhile, tankless systems operate only when you turn on the tap, making them more efficient.

Types of Tankless Water Heaters

Tankless water heaters come in two main types (gas or electric):

1. Electric Tankless Water Heaters: These units heat water using electrical heating elements. They are typically smaller and easier to install, making them a popular choice for homes with limited space or where a gas line isn’t available.
   
   
2. Gas Tankless Water Heaters: Gas-powered models use natural gas or propane to heat water. They tend to have a higher flow rate, which means they can supply hot water to multiple fixtures simultaneously (you can run the washing machine without having a cold shower).

How a Tankless Water Heater Works

A tankless water heater works by heating water as soon as it starts passing through the unit. Here’s a look at the process:

1. Water Starts Flowing: When you turn on a hot water faucet or appliance, cold water enters the tankless unit through a supply pipe.
   
   
2. Water Is Heated: An electric element or a gas burner quickly heats the water as it circulates around a heat exchanger. The water is at the right temperature as it exits the unit.
   
   
3. Hot Water Is Delivered: The now-heated water flows directly to the faucet or appliance you are using. When a plumbing fixture is turned off, the heating element shuts down.

This is what makes tankless water heaters “on-demand”. It also contributes to significant energy savings. Fewer fossil fuels are needed to heat water. A tankless system can be up to 34% more energy efficient than a tank-type water heater (depending on the model).¹

FAQs

Can a tankless water heater increase my water bill?

A tankless water heater typically reduces energy costs. How much your water bill decreases depends on the amount of hot water you use.

Should I replace my hot water heater with a tankless system?

If your current water heater is old or inefficient, or if you want to save space, a tankless water heater could be a great replacement. However, we recommend assessing your home’s hot water usage first.

What maintenance does a tankless water heater need?

A tankless water heater requires regular maintenance, including descaling the unit to prevent mineral buildup, especially if you have hard water. It’s also important to replace the air filter and clean the heater’s exterior.

Call Lynch Plumbing for Tankless Water Heater Installation and Repair

At Lynch Plumbing, we provide tankless water heater installation and repair in Los Angeles and the San Fernando Valley. If you’re considering making the switch, we can help analyze your current hot water usage to determine if a tankless system is suited for your household. Call (818) 773-9514 today for professional advice, to schedule a consultation, or to get a free quote.

Sources:

U.S. Department of Energy. Tankless or Demand-Type Water Heaters.