27
FUNCTIONAL DIAGRAM
Fig. 32
NOTE. L-N-E CONNECTION MUST NOT BE INTERCHANGED
CONTROL SWITCHING OF TIME CLOCK AND ROOM THERMOSTAT RATED IS 230 V.a.c.
Key
F Hv
Fan power supply 230 V
F Lv
Fan signal control
E.P.
External pump
F
Fuse 3.15A F (fast)
F1-F2
Fuse 3.15A T (delay)
OPE
Gas valve solenoids
S.E. (1)
Spark electrode
S.E. (2)
Sense electrode
C.S.
Condensate sensor
G.V.
Gas valve
TSC1
Ignition transformer
TR2
PCB transformer
FS
Flow thermistor (NTC)
RS
Return thermistor (NTC)
AD02A
Main PCB
CN1÷CN5
Connection to PCB high voltage
X4÷X9
Connection to PCB low voltage
F.O.H.T
Flow over heat thermostat
H.E.T
Heat exchanger thermostat
M3-M5
Terminal strip for supply in / clock / room thermostat
M3a
Terminal strip for esternal pump
X1
Connector minitank (unused)
CN12
Service connector
SW1
Co button
A1
24V output to 2CH - programmer
P2
Heating potentiometer
P3
Selector switch
R9
Trimmer for maximum output
R10
Trimmer for minimum output
R14
Trimmer for ignition fan speed
R19
Trimmer for heating fan speed
R35
Trimmer thermoregulation