How Does a Gas Tankless Water Heater Work?

Gas Tankless Water Heater

How Does a Gas Tankless Water Heater Work?

In order to understand how a Gas Tankless Water Heater works you first need to know how a conventional water heater works.  It is nothing more than a tank filled with water and equipped with a heating mechanism (it looks like a big metal cylinder and is often found in a garage or basement).  The water in the tank is continuously heated.  Hot water is drawn from the tank and is replaced by cold water.  The heating mechanism heats the incoming cold water to the desired temperature.

There are at least three issues associated with a conventional hot water heater that you need to be aware of.  First, once all the hot water has been drawn from the tank it takes time for the cold water that has entered the tank to be heated (this is why you try to take your shower in the morning before your teenager!!).  Second, the water in the tank is constantly heated – even when you are not using it or are not even home.   Third, even if no hot water is being drawn from the tank, the heater must operate periodically to maintain the water temperature.  The energy used to keep the water hot even when it is not being used is called standby heat loss.  These standby losses represent 10% to 20% of a household’s annual water heating costs.

Gas Tankless Water Heater

A Gas Tankless Water Heater (also called an instantaneous or on-demand water heater) avoids standby losses by heating incoming water only as it is needed.  A Gas Tankless Water Heater uses a powerful heat exchanger to heat the water.  When you turn on a hot water faucet a flow sensor in the Gas Tankless Water Heater activates the heat exchanger.  As the incoming cold water passes through the unit it is heated by the activated exchanger.  The result is a continuous supply of hot water that is heated only when it is needed and never runs out.

As you can see a Gas Tankless Water Heater avoids the issues associated with a conventional water heater.  Since there is no tank, there is no water to keep hot, and, therefore, there are no standby losses.  By heating water only when it is needed, instead of maintaining a tank full of hot water at all times, a Gas Tankless Water Heater can achieve greater efficiency than a conventional water heater.  Also, the quality of the hot water is not affected by rust and scale inside the tank., and since there is no tank, there is no way the unit may spring a leak and flood your basement or garage.

A Gas Tankless Water Heater will last about five to ten years longer than a conventional heater, take up much less space, and provide you with an endless supply of hot water.  Using a Gas Tankless Water Heater can also save you a substantial amount of money every year on your monthly water heating bills. 

Gas Tankless Water Heater

Please continue reading my Tankless Gas Water Heater – 3 product review  and visit my Tankless Gas Water Heater Store.

Also see my other review posts for this green living product: 

Ten best features for tankless gas water heaters.

What makes a tankless gas water green?

Tankless gas water heater FAQs.

On demand gas water heater Tips and Tricks.

Thank you for visiting, and for supporting Switch it Green, Switch it Forward.


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