How a Tankless Water Heater Works- Home Improvement Tips

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Tankless hot water heaters are the future of energy-saving during hot water production. Traditionally, hot water heaters operate with a tank that heats and stores water twenty-four hours a day.

This means that a significant amount of energy is used to heat (and re-heat) water, even when you’re not using it. This is a waste of both energy and money.

Tankless water heaters are now an available alternative. Here’s an explanation of how a tankless water heater works.

A tankless hot water system is the energy-efficient way to heat and use hot water. The crux of the system is that it heats water only as you need it. They work by heating water directly. For this reason, they are sometimes also referred to as “on demand” water heaters.

How a Tankless Water Heater Works Actually

When you turn on the hot-water faucet, cold water enters the tankless system through a pipe. The system then starts operating. It uses a heat exchanger underneath the pipe to heat the cold water. A heat exchanger transfers heat from one source to another.

In a tankless water heater, the heat exchanger is either electric coils or a gas-fired burner. The hot water then flows to your faucet. When you turn off the hot-water faucet, the system goes into standby mode.

Thus, water is only heated when you turn on your hot-water faucet, AKA: when you need it. Due to this operation, tankless water heaters can be subject to lag time, the time it takes for hot water to flow to your faucet.

So, you could be waiting a while for hot water if your tankless system is quite some distance away. They also provide water at a slower rate than tank water heaters, at roughly 2 to 5 gallons per minute. Therefore, you may not be able to use multiple faucets at once.

To combat this, there are two types of tankless water heaters. The first is a point-of-use heater. This means it is only installed for one particular water source in your home.

For example, it may operate only for your bathroom sink. These systems are small and can be fitted in confined spaces, such as under cabinets. An advantage of this is that they can be fitted closer to the source of water and help lessen water loss during lag time.

The second is a whole-house heater. As the name suggests, these systems heat water for your whole house, and are therefore much larger than point-of-use systems. They can heat up hot water for multiple faucets at once and are often operated with gas or propane.

Generally, tankless water heaters that are gas operated will provide water at a higher rate than electric ones.

How a Tankless Water Heater Works

Tankless heaters are also built to last between five and 10 years longer than a traditional tank heater.

However, a tankless water heater is often much more expensive to purchase to begin with, but will likely save you money on gas bills in the future. Additionally, they require maintenance and potential upgrades which can be expensive.

The best tankless water heater is one that is suited to your home and water consumption, and provides hot water at a high enough rate that it increases your energy savings.

Consider size, fuel type and if that fuel type is available, energy efficiency, and cost when searching for a tankless water heater.

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by Shelly Rhoades
Having recognized the need for accessible and affordable solutions in the remodeling industry, Shelly founded Affordable Kitchen and Baths with the mission of helping homeowners create their dream spaces without breaking the bank. Her dedication to providing reliable advice and quality resources has garnered her a loyal following and established her as a go-to resource for anyone looking to transform their kitchen or bathroom.

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