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3.18 SOLAR PANELS COUPLING FUNCTION.
The boiler is prepared to receive pre-heated water from a system
of solar panels up to a maximum temperature of 65°C. In any case,
it is always necessary to install a mixing valve on the hydraulic
circuit upstream of the boiler, on the cold water inlet.
To optimise the operation,where the probe is not already fitted
on the boiler, the solar inlet probe kit is available on request (see
wiring diagram Fig. 37):
if there is no probe kit, it is advisable to set parameter A6 (DHW
thermostat) at “1”;
otherwise, where the kit is installed or the probe is already present
in the boiler, parameter A6 must be left at “0”. This kit allows
connecting a probe on the domestic cold water inlet pipe of the
boiler to prevent unnecessary ignitions in systems with water
heating through solar systems or alternative sources. The boiler
will not turn on if the inlet water is sufficiently hot.
In both conditions (probe present or not), we recommend setting
parameter t3 (solar delay timing) at a time sufficient to let the water
inside the D.H.W. circuit upstream of the boiler drain.
The greater the distance from the storage tank, the longer wait
time will have to be set.
With these adjustments made, when a domestic withdrawal is
requested, once the time set on parameter “t3” has passed, if the
water entering the boiler is at a temperature that is equal to or
greater than that set, the boiler will not turn on.
Note:
in order for the boiler to work properly, the temperature
selected on the mixing valve must be 5°C higher than the tem-
perature selected on the boiler control panel.
3.19 PUMP ANTI-BLOCK FUNCTION.
The boiler has a function that starts the pump at least once every
24 hours for the duration of 30 seconds in order to reduce the
risk of the pump becoming blocked due to prolonged inactivity.
3.20 3-WAY ANTI-BLOCK SYSTEM.
Both in “domestic hot water” and in “domestic hot water-central
heating” phase the boiler is equipped with a function that starts the
three-way motorised group 24 hours after it was last in operation,
running it for a full cycle so as to reduce the risk of the three-way
group becoming blocked due to prolonged inactivity.
3.21 RADIATORS ANTIFREEZE FUNCTION.
If the system return water is below 4°C, the boiler starts up until
reaching 42°C.
