Installation manual

GENERAL DESCRIPTION AND INTRODUCTIONSECTION 1
PRE-HEAT
SYSTEM
LEGIONELLA
DESTRATIFICATION
CONTROL
In a pre-heat systempre-heat system the water in the cylinder is heated only by the solar. This is discharged
to a secondary device e.g storage calorifier/direct-fired water heater. These can be supplied
as part of the SOLARflo system. If the secondary device requires primary hot water a primary
system can be included.
The standard systems supplied with SOLARflo use direct gas fired water heaters.
The ‘top up’ system is also required to ensure anti-legionella temperatures are reached and
d
e-stratification measures can take place
One of the main differences between commercial and domestic solar thermal systems is the
requirements of L8, the control of legionella. Temperatures must be able to achieve 60°C and
above. The ‘top up’ system must take the storage water to 60°C if the solar energy is not
able to do so.
DestratificationDestratification
e
quipment is supplied on both types of systems to ensure all the water within
the cylinder is heated to anti-legionella temperatures.
For pre-heat systems the water is taken from the outlet of the ‘top up’ system and fed to
the bottom of the solar cylinder. For combined cylinders with twin-coils a destratification loop
pumps hot water from the top of the cylinder to the lower section.
The controller is designed to integrate the whole SOLARflo system from solar pump control
to operation of the destratification cycle.
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