The initial cost of installing a solar hot water heater can be expensive but once installed will pay for itself over a relatively short period of time.

Our summer temperatures here reach a maximum of 47° Celcius which creates the ideal oppurtunity to install a solar hot water unit. Although our solar hot water unit is mounted on a roof facing slightly to the north of west (we are in the southern hemisphere) we find that in the warmer to hotter months it does a great job. A number of people have had problems with their solar hot water units by having them mounted on a roof facing due north. In the hotter months the water has boiled and resulted in water wastage. Have a good think about the position of your unit and if in full summer sun see if it is practicable to have some sort of moveable shade that can be used if the water becomes too hot. A blind operated from the ground is inexpensive.

Be very careful about buying a system that has a bleed valve that lets hot water escape when a certain temperature is reached because if you live in an area like us water is too precious to waste.

As there is only the two of us in the house for most of the year we purchased the smallest unit available at the time. Ours is a single panel with a header tank that holds 180 litres of water. In the summer months we only feel the water temperature drop if there are several days of cool, cloudy conditions in a row.

We normally light the wood burner to help heat the water for about six to eight days over the summer which is not a problem.

In the winter time the wood burning stove is used nearly every day for cooking and at the same time it heats the water in the solar storage unit.

It is interesting listening to some so called solar experts who say that you can only have gas or electric backup on a solar hot water unit. We run our backup via our wood burning stove and it works great. When we purchased EarthWood there were two water sevices here, one for the wood burning stove and the other ran on gas. It is far easier and cost effective to have only the one hot water service and the choice of backup is yours.

I have met a couple who were told by a local plumber that solar hot water does not work in this area and then sold them an electric hot water service. Solar hot water systems work anywhere the sun shines, to what degree depends on the sun, not a plumbers lack of knowledge or greed to push a product he can make the most profit from.

There are two types of solar water heaters on the market. Ours is the type where the water in the panels acts as a heat carrier to the header tank. Because of this the water in our panels has anti-freeze in it as we get temperatures of - 4° Celcius in the winter. In the other system the water in the panels circulates directly into the header tank therefore I would imagine can reach greater temperatures.

All solar water systems come with either an electric or gas heater but these do not have to be connected if you want to heat the water from a wood burner stove or another heat source.

A hint with installation. Make sure that all pipes are under cover or suffiently lagged as we did experience some minor problems with frozen pipes when visited by Jack Frost at the start of the first winter it was installed. The installers who installed our unit should have known better than to run the feed pipe across the roof. It took seven phone calls and a threat of wanting our money back before they returned and put the feed pipe where it was supposed to go.

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