Thermal Control In The "C.h." Mode - Biasi Activ A 12OV Service Manual

6.7

Thermal control in the "c.h." mode

circulator off
fan still
Is primary circuit
YES
temperature higher than that
starts ignition discharges
Opens gas valve
beginning of ignition period
NO
NO
Is fan rpm
exact?
safety thermostat or flue
NO
temperature probe lock out?
Fig. 6.12
Switch in the c.h. function mode
Request for heat from
NO
room thermostat?
selected?
NO
YES
starts fan
checks fan rpm
Is fan rpm
NO
exact?
End of wait
YES
period?
YES
End of ignition
period?
YES
YES
YES
circulator on
Temp. difference
NO
between probes
higher than 35˚ C ?
lock memorised?
temperature higher than 110˚C?
YES
flame presence?
NO
flame presence?
NO
closes gas valve
stops fan
interrupts ignition discharges
memorizes lock
display show lock--- out
reset key
NO
pressed?
flame presence?
Main electronic control/ignition p.c.b.
YES
YES
NO
cancels lock
Is flue
YES
beginning of wait period
YES
interrupts ignition discharges
YES
gas valve open
fan runs
YES
NO
stop circulator (3min)
NO
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