EcoSolar Energy Conscious Design Limited
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to achieve. Another option, although having a greater capital cost, is to install a preheating solar
system, these options will be discussed in greater detail in a future article.
For maximum savings when installing solar on to gas heated cylinders a solenoid valve is installed on
the main gas burner line to hold off the main burner, the solenoid is then initiated by a timer. This
will also be the subject of another future article.
Legionella
Unless the hot water cylinder is being heated regularly to greater than 60
O
C, there is a risk of
Legionella establishing itself in the hot water cylinder. In order to minimize this risk the water should
be heated to 60
O
C for 6 hours once a week. This function can be manually managed or EcoSolar are
able to supply controllers or timers that take care of this function for you. If you are managing this
yourself we recommend that the water is heated at the same time each week this way the
management will hopefully become habitual. If the cylinder has two immersion heaters the lower
one should be initiated to maximise the amount of water heated.
Please note that the above will limit but not prevent Legionella from establishing it’s self in the hot
water cylinder. The shower head is most at risk most pipework is also a risk area. All the pipework
should be regularly flushed to limit the establishment of Legionella this is the case on all hot water
systems, more so where tempering valves are installed as the water downstream of the tempering
valve only reaches 45
O
C which is an optimum temperature for Legionella growth.
Safety
In addition to the normal conventions for safety, when installing or working on the system please
take note of the following;
•
Isolate electrical supply to controller, pump and electric water heater booster
•
Wait for the system to cool down
•
Wear protective clothing due to sharp edges and hot components.
•
Turn off the water supply
•
Release the water pressure using the relief valves
•
Cover the collectors and pipes etc with cardboard or sheets to limit heat gain from the
sun
