Electric Hot Water Heaters

In spite of what anyone might say – or hope – electric hot water heaters are still the most commonly and widely used type. But there are so many different varieties, with vastly different features to one another, it can be a minefield trying to decide which is the best electric hot water heater to buy.

Electric water heaters available today

While different manufacturers have different products that you should review before you decide which to purchase, there are certain basic types on the market. These include:

• Instant water heaters that generally fit above or below a sink or basin, and deliver hot water instantly when you turn on the faucet. The most basic instantaneous electric water heaters simply have a coil or element inside them, like a kettle, that heats up the water. These are generally quite small, so they are only suitable for heating small quantities of water at any one time.
• Tankless water heaters, like instantaneous models, do not incorporate a cylinder to hold water but (unlike the small, traditional instantaneous models) they are able to continuously heat the flow of water through the unit.
• Push-through water heaters (also referred to as open outlet water heaters) incorporate an inlet valve that opens to allow cold water to flow into the cylinder, literally pushing the hot water that has been heated by a thermostat inside the cylinder, out through the outlet pipe. Basically a control valve regulates the flow of water through the outlet. An obvious advantage of this sort of hot water heater is that because it is vented to the outside air through the open outlet, the water inside the cylinder is not held under pressure, and therefore it cannot superheat and burn you (or explode!).
• High pressure hot water heaters aren't vented or open to the atmosphere. They draw water directly from the mains supply, through a pressure control valve, and are designed to work at various different pressures, commonly from 100 kPa – 600 kPa (100,000 to 600,000 pascals, which is of course a measure of pressure). The flow of hot water is controlled on the outlet side by faucets attached to baths, basins, showers, sinks and so on. An advantage of high pressure water heaters is that installation can be carried out at any level. This means you can put the heater in the roof space, in a garage adjacent to the house, or even below a sink. They are often fixed to a wall and then built in, with suitable access for the plumber should there be a leak or any other problems.
• Combination hot water heaters are vented, non-pressure water heaters that work in a similar way to the push-through type, except that the flow of water is controlled at the outlet, rather than the inlet. Also, they are fed by a tank and the water generally flows because of gravity pressure – which means that the tank needs to be elevated. Traditional combination water heaters aren't very popular nowadays because the pressure in the cylinder itself is very low, and so they don't work too well with mixer taps and showers. Just bear in mind that these types are not necessarily absolutes, and you need to identify the features you require to be sure that any rating the unit has been given is relevant to your needs. While all of these types might be found in older homes, if you are shopping for a new hot water heater, you'll be well advised to buy models that incorporate new technology.

Features to look out for

Whether you are planning to buy a conventional water heater, one that is tankless, or perhaps a contemporary hybrid model, these are some of the features that might appeal to you. Of course the prices charged will also be important, as will the availability of spare parts.

In today's day and age, one of the most important issues relating to water heaters (or geysers as they are sometimes called) is energy efficiency, particularly in terms of energy savings. And there are lots of options. Hybrid electric heat pump water heaters are extremely versatile and more energy-efficient than most other types.

Hybrid heaters that combine features of conventional and tankless technology are also worth looking at. A good model will perform like a tankless heater, but will be able to handle the high hot water demand of busy households.

Durability is another issue, so look out for designs that will reduce the buildup of lime and other sediments. Related to this is longevity; you will find that some top quality designs feature heating elements made of new age materials that are expected to last up to three times longer than the standard copper elements we have become so used to.

So shop around and compare what the different types of water heaters have to offer before you make a choice in terms of which is the best electric hot water heater for your home.