EcoSolar Energy Conscious Design Limited
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Figure 25. Mains pressure hot water drainback system using a heatstore cylinder
Reliability
As a solar water heating system returns savings over an extended period of time and is generally not
located in an readily accessible position, the system needs to be installed and operate with minimum
intervention from either the owner or the installer. We all have a duty to ensure the systems we
specify or install are fit for purpose and will provide maximum savings for the client. Incorrectly
designed and installed systems will not only provide headaches for those involved in that particular
installation but it will have a significant impact upon how the industry is perceived and whether such
systems are seen as an appropriate solution to the rising cost of energy and the impact to the
environment.
Existing hot water cylinder heating Source
Once the solar hot water system is installed the existing hot water heating source needs to be
managed to minimise the energy consumed heating water, maximise the use of the solar heating
system and minimise the risk of Legionella forming within the hot water cylinder and system.
Under normal circumstances the heating source is turned off and is only turned on when additional
hot water is required or to minimise the risk of Legionella. There are several options to manage the
heating source, manually or automatically.
