Tankless Hot Water Heaters

On demand or tankless water heaters have come a long way since the early instantaneous models that were intended for cloakrooms and small business offices. Today most water heaters that are tankless are considerably more sophisticated, and they are considered to be generally energy efficient.

Most tankless heaters will last at least two decades. Better still, if anything does go wrong, replaceable parts are normally easily available and relatively inexpensive when compared to those required for storage water heaters. But they do still have their drawbacks, so it's wise to read a review or two on the specific heater you plan to buy, before you make a final decision, irrespective of how reasonable prices may appear be.

How tankless hot water heaters work

Like all instantaneous heaters, those without a tank heat the water without needing to store it in a cylinder or tank. When you turn the faucet or tap, the cold water enters the unit through a pipe and is then heater by either an electrical element, or some sort of gas burner.

The main advantage is that instead of having to either wait for the tank to fill – or for the cold water in the tank to get hot – you literally do have hot water on demand. Since there is no tank (or cylinder), these units take up less space. Also, you won't have to face the potential problems of rust, lime and scale forming on the inside of the cylinder.

Energy efficiency

If you consider the fact that turning off your hot water cylinder when it is not in use saves money, it stands to reason that if you don't have a cylinder – or tank – the energy losses normally associated with storage water heaters won't occur. Furthermore, the water is only heated once, when you need it. quite simply, when you turn off the tap, the heater stops working. With a cylinder, on the other hand, you ultimately end up heating and reheating the water in your tank, wasting whatever energy it has taken to heat the water that has been heated, but isn't used.

Manufacturers do point out, however, that to optimize the energy efficiency of any tankless unit, installation must be carried out correctly.

Disadvantages of tankless hot water heaters

Most of the tankless hot water heaters on the market will provide hot water at a rate of between 2 to 5 gallons or 7.6 to 15.2 liters per minute. But be aware that the output will limit the flow rate.

While gas-fired designs generally supply a higher flow rate than most electric models, there are relatively few that are able to supply sufficient water for multiple appliances that are frequently in use at the same time. This can cause problems in the household, which can, in turn, be disruptive.

Modern tankless heaters

Nowadays leading manufacturers make water heaters that are designed specifically for different regions, including North America. One leading German company that has been in the appliance industry for well over a century makes two types of electric tankless water heater designed specially for North America (parts of the USA and Canada). Designed for heating all types of appliances, they have a model that will provide 3.7 gallons every minute at a temperature of 105 °F, either to a shower or a bathtub, or to two sinks (or a basin and a sink) at the same time. It will also provide 3 gallons per minute at 115 °F, which makes it perfect for running a dishwasher. This company's other model is similar but a bit smaller and it provides 2.3 gallons every minute at a temperature 105 °F or slightly less (2 gallons) at a temperature that is a little (at 115 °F) – although this one is only suitable in areas that experience an average yearly ground-water temperature that is more than 60 °F. But it all goes to show that you can find tankless units that successfully service two appliances at once.

Another German company that supplies the international market (including North America) prides itself on its leading edge tankless water heaters that feature sensors and microprocessors. These automatically adjust the water flow rate and pressure, as well as the temperature of the water. This company maintains that using their hot water heaters will successfully help you cut energy costs by as much as 50%! When you activate one of these units (by turning on the tap) the flow sensor recognizes that the water is running and its heating elements go on. When you turn the tap off, the unit switches off and immediately stops using energy.

A well-established Japanese manufacturer operating in the same region also claims 50% energy savings, together with space saving.

And there are lots of others like them.

If you have a look at a review of some of the newer hot water heaters currently on the market, you'll get some idea of the current rating of each. You will also be able to assess whether there are any known problems or specific disadvantages of any of them. Reviews compiled by real consumers are particularly worthwhile since manufacturers generally focus on positive factors only. For example, they would never suggest that a leak could possibly occur if a particular valve stopped functioning fully. But if a consumer has had that problem, they will share it in their review.

With this information, and some basic knowledge of what to look for, you'll be sure to find the best tankless hot water heater to suit the needs of you and your family.