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61
AST 14 C 255/00
P17=2 Solar plant reference:
BOILER INTEGRATION
(P18=0)
only for CTFS
Management of a solar plant deviating valve (VM):
The function consists in properly controlling the motorised valve VM by means of
the multifunction relay and
in activating the boiler burner only if the solar water heater
temperature is sufficient to fulfil the request for operation
.
This valve is controlled by a solar water heating probe (SBS) located at the water heater
output.
The VM valve remains in the rest condition (boiler integration) when the temperature
detected by the SBS probe is lower than the DHW set-point temperature - 2°C. Instead, it
is supplied with power (solar-only mode) when the solar water heating probe temperature
reaches the DHW set-point set in the boiler, or in case of probe fault.
When the VM valve is in solar-only mode, the boiler will not perform the DHW function.
Warning: said function is active only if either the DHW + CH, or the CH ONLY or DHW
ONLY mode is selected in the boiler. With boiler in OFF or ANTI-FREEZE mode, the VM
valve is constantly supplied with power.
Any probe faults are reported in the boiler interface or on the remote control through the
relevant error code (E28).
Electrical connections:
VM
21 22 23
21 22 23
