A tankless water heater can usually operate based on the concept that it would be heating water as it is needed. They are a lot different from the traditional hot water heaters which typically requires storage tanks since tankless water heaters do not any kind of storage tank which would mean that you would not be experiencing any standby heat energy loss. This standby heat loss would be the amount of heat which is lost and the energy which is wasted when water is heated and then stored in a tank. This is the general feature of the traditional hot water heaters which is completely eliminated by tankless water heaters, as it avoids any standby heat loss making them a lot more energy efficient.
Regardless of the kind of tankless water heater you would be getting, like a whole-house unit or a point-of-use one, they just usually function the same way. Cold water would be entering the unit which would then be heated through the use of a heating element or a heat exchanger that could be turned on with a flow activated switch. This heat exchanger could be a gas fired burner which uses propane or natural gas or could be several electric resistance heating coils.
Generally, there are three factors that you would need to consider as you size the unit. These would be the temperature of the entering cold water, the temperature desired for the exiting water and the volume of water which would be required to be heated by the unit. The water volume is typically measured in GPM or gallons per minute, which would be the flow rate.
These three factors would be able to help in determining the type and size as well as the how many tankless water heaters you would be requiring. There are generally two kinds or types of the tankless water heaters, the first one being the point of use units and the second one being the whole house units.
Point of use units of tankless water heaters have the ability to churn up 170 degree Fahrenheit of hot water almost instantly. You could easily pour the water which is ready in making coffee or soup or tea right from the faucet. This kind of tankless water heater is small and compact enough to be able to fit in a small closet or under a sink cabinet. These are usually dedicated use water heaters which would mean that one unit would be dedicated to just one faucet. These are much less expensive compared to the whole house water heaters.
The whole house water heaters, on the other hand, could provide a much higher flow capacity. They could also handle demand that would be for more than just a single fixture simultaneously.
You could try to read more online and research on the benefits of switching over to tankless water heaters. Once you have made the switch, you would surely be able to save a lot of energy, not to mention money.
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