Immergas HERCULES Condensing 26 2 E Manual page 26

Technical Documentation
Functioning with solar panels kit (optional).
The two coils (4-5) in the storage tank are set-up vertically one
above the other and, in standard configuration, are connected
hydraulically in series (see DHW hydraulic diagram) in a way
that their total surface guarantees heat exchange of all of the
power supplied by the appliance.
Their dimensions differ so that, in normal working conditions,
the upper one (4) exchanges 24,000 kcal/h and the lower one
(5) 4,000 kcal/h.
The installation of the "solar panels kit" envisions the sepa-
ration of the two coils and connection of that set-up in the
lower part of the storage tank (5) to the MP (panels flow) and
RP (panels return) connections of the boiler connection unit.
In this way, while the other coil (4) remains connected to the
boiler circuit, this is fitted to an external solar panels system
(not supplied in the kit).
The application of the above principle diagram, envisions
the use of a control unit (3) that detects the temperature of
the storage tank water via a sensor (6) to be positioned in the
bulb-holder present on the lowest storage tank. This leads to
shifting the DHW NTC probe (14) in the immersion sample
point present on the highest storage tank.
The control unit (3) controls the pump (2) when the sensor
STHCkW ed 0409
Boiler
circuit flow
Boiler
circuit return
MP
RP
Technical Documentation
(6) detects a temperature lower than that requested and than
that of the water heated using the panels.
If the intake of solar energy is not sufficient to satisfy require-
ments (prolonged withdrawals, little insulation, etc) and the
boiler DHW NTC probe (14) measures a temperature lower
than that set, the burner is started and the upper coil (4)
guarantees the instantaneous production of DHW (24,000
kcal/h).
Solar panel circuit leaks graphics.
The solar panels circuit inside the boiler (coil and connection
pipes) have the head losses represented in the graphics at the
side, which must be taken into consideration for the dimen-
sioning of the pump (2).
14
6
24
AC
AF
MP
RP
4
5
Flow rate litres/h
HERCULES Condensing Export