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How Does an Instant Hot Water Heater Work?

How Does an Under-Sink Instant Hot Water Heater Work?

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Whether you’re craving a quick cup of coffee, a warming bowl of soup or a hot toddy, you can satisfy that desire in an instant thanks to the marvels of modern technology. Unlike whole-house tankless water heaters, instant hot water dispensers are designed to immediately deliver hot water straight from the faucet.

These point-of-use systems are extremely convenient for busy households. You can get small quantities of hot water preheated to a precise temperature at any time without the need to heat water on the stove or in the microwave.

Let’s take a look at these nifty systems and how they work.

Designed to be installed under the sink, most instant hot water dispensers produce up to 60 cups of water an hour. Some units are adjustable with options ranging from 140 to 190 degrees F, so you can select a temperature that suits you. Others are designed to heat water to a specific temperature determined by the unit and maker. Preset temperatures vary, but many units are designed to heat water to 200 degrees F or slightly below boiling point. If you plan to use your instant hot water system to make coffee, choose a unit that achieves a temperature between 190 and 205 degrees, the ideal range for brewing a delicious cup of coffee.

Essentially there are three parts to the system: An inline filter, a heating/holding tank and the dispenser or faucet. The inline filter is connected to the cold water supply line to remove impurities so your hot water is crisp, clear and unclouded. From the filter, water is channeled into the heating unit. Most consist of two chambers: One holds a supply of cold water. The other heats the water and holds it at a steady temperature, so it’s instantly available.

The Process
The moment you open the tap, hot water flows out. As the hot water leaves the heating/holding tank, filtered cold water is drawn from the cold holding chamber into the hot water chamber where it’s heated. At the same time, cold water is pulled through the filtration unit and funneled into the cold water holding chamber. It’s a simple and effective process that occurs in less time than it takes to describe it.

For obvious reasons, most instant hot water dispensers are installed in the kitchen. You can quickly prepare a cup of tea, coffee or cocoa, make instant oatmeal, cook ramen noodles, make soup in a cup, speed up food preparation, remove labels, clean utensils and much more.

See also: 

Types of Instant Water Heaters for Home Use

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