Before we explain how a tankless water heater works, let’s talk a bit about how a standard/traditional “tank heater” operates. Tank heaters have a large tank that holds and heats water (thus the term “tank heater”). The tank continually heats water in order to maintain a constant temperature. The energy used to keep hot water hot even when you’re not using it is called “standby heat loss”. Here’s a good article about “How Standard Hot Water Heaters Work”.
Standby Heat Loss in Water Heaters
If you haven’t guessed it yet, the big savings from tankless water heaters come from eliminating standby heat loss. in other words, tankless systems only heat water when you need it, so you don’t spend money to boil water for hours before you need it. The tankless hot water heater operates efficiently to just heat the water when you need it.
Heat Exchangers in Tankless Water Heaters
Of course the tankless heater still needs to use energy to stay hot and be ready for your shower. So here’s how that works: a tankless hot water heater uses something called a “heat exchanger”. This device “exchanges” heat generated by electric coils or a gas-fired burner to the water which will come out of your faucet. The exchanger is activated when water begins to flow into the system. The incoming water circulates through the exchanger, which heats the cold water. So, the system only “turns on” when you ask it to being heating water.
Types of Tankless Water Heaters
There are two types of tankless hot water systems: point-of-use and whole-house heaters. A point-of-use system is small and only heats water for one or two faucets (like two sinks in your kitchen). They can fit under a cabinet or in a closet. Point-of-use systems can be more efficient since they reduce the time between when you turn on the hot water faucet and when the hot water actually comes out of the tap. This saves water, since you’re not spilling cool water out of the tap while you wait for the hot water to come. Whole-house-heaters are larger and can operate more tank one outlet at a time (thus the term “whole-house-heater”).
Point-of-use tankless water heaters are usually electric. Whole-house systems are usually natural gas or propane. There are a number of factors to consider when deciding how to power your heater and which model you should choose. Henry Plumbing has tankless water experts happy to answer your questions and help you choose the right hot water solution for your home or business. Call us at 912-352-9827.