An Englishman by the name of Maughan invented the first tankless water heater in the 1870's, the idea being to heat the water almost instantaneously and only when the water was needed. Like many other inventions, the tankless water heater went through a number of designs over the years with the most prominent design being able to heat the water at the point of use.

This meant that anywhere hot water was needed a small gas or electric powered heating unit would be located so there would be at least of couple of units in a home, a small one in the kitchen and probably a larger one in the bathroom, each of which could produce hot water in a matter of seconds.

Now, years later, technology has advanced to tankless water heaters, also known as on-demand water heaters. These heaters do exactly what the name implies, they provide hot water only when it is needed and this is true even when large amounts of water are required at several locations at the same time. An example of this might be someone taking a shower while the washing machine is on, or a bathtub being filled with hot water without anyone being concerned about hot water going into the washing machine at the same time.

This tankless technology is totally dependable regardless of whether the home uses gas or electricity to heat the heater and because there is no energy used to keep water hot there is no standby heat loss and no concern about running out of hot water in the middle of the shower.

A normal shower uses about 2.5 gallons of water per minute and a tankless water heater can supply approximately 6 to 7 gallons of hot water per minute. These heaters can be considered green products with very sophisticated computer controls set to keep the water temperature at its preset level regardless of the water pressure and volume.

Because a tankless water heater has no storage tank it comes in a small package, about five time smaller than a heater with a tank and it can be mounted on any outside wall of the house thus saving valuable space either in the home or the garage wherever the unit would have been located.

Another great advantage to having a tankless heater is that once it is installed there will never be a need to call a plumber for a tank cleaning or repair. In case of a malfunction the system turns itself off and provides analytic and diagnostic information. There are also no safety issues because there is no permanent pilot and its burner, electronically ignited, comes on only when hot water is needed. The electronics also monitor the incoming water pressure and flow as well as the outgoing flow and water pressure, so hot water is always guaranteed.