Selection of a water heater needs considerable care. The decision you make will last for many years. Remember, you want enough hot water to meet the whole families needs all the time, even in winter.
You do not want to make the wrong decision which can lead to years of an unsatisfactory supply of hot water or expensive running costs.
Your water heater selection falls into two categories - replacement or new installations. Either way consider all the facts before making your choice. In a replacement situation, a broader review of the facts may highlight a better or cheaper way of supplying hot water.
Whether it is a replacement or new installation you are considering, the following alternatives need to be assessed.
Fuel Type
Domestic water heaters are designed for use with either gas, electric or solar power. The facts needed to choose between them are:
Is reticulated gas available?
If not, is there a reliable source of LPG in the area?
Is an off-peak electrical supply available?
Is the house in a good solar location and is there a suitable north facing roof?
What fuel will other appliances in the house be using?
What is your preference?
Consider each fuel, ensuring all information is available to make a choice. Running costs are also an important consideration. Check with your local fuel authority as to the fuel tariff for water heating.
Combining gas water heating with gas cooking may attract a cheaper tariff from the gas authority. Gas fuel offers an economical 24 hour recovery for hot water.
Off-peak and controlled electricity tariffs can offer substantial savings on your electricity bill. Water heaters connected to these tariffs must be large enough to store hot water for the period when no electricity is available to them.
A decision to install solar water heating can often be made on economic grounds. Savings in running costs make the additional purchase cost of a solar water heater feasible.
Consider connecting the booster heating unit of the solar water heater to an off-peak tariff for further savings.
Where solar savings may not be so great, you may be prepared to gain long term benefits in energy conservation, pollution reduction and growth of running cost savings.
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