Test your knowledge:

1. Why does the temperature of the water rise and fall over a 24-hour period?
2. Why do you think the temperature of the water is not the same everywhere inside the tank?
3. This solar hot-water heater does not have a pump. Explain how water is able to flow between the storage tank and the collector.
4. Would it be better to place the storage tank above or below the collector?
5. Why is black the best colour for the collector?
6. Why was the sensor from the coldest part of the tank used to decide whether Legionella bacteria may be present?
7. If there is a water shortage in the community, why is it important that the water in the solar hot-water heater is kept well below 100°C?
8. This solar hot-water heater is located in Melbourne. However, it was designed to be used in hotter areas such as outback Australia. How could you stop the growth of Legionella bacteria in this system in a cooler area like Melbourne.