Installation / Operation Instruction Manual

50
WARNING
DO NOT adjust any dipswitch settings on PC board except dip switch number 1, if required, for vent
length or unless instructed to do so.
RELAY 1
IG
FROST SENSING
SWITCH
ANTI-FROST HEATER
IGNITION
COMBUSTION
FAN
3A(FUSE)
HOT
NEUTRAL
VARISTOR
DC12.6V
SOLENOID
DRIVING
CIRC U IT
CPU
CENTRAL
PROCESSING
UNIT
FAN
REMOTE
CONTROLLER
POV
FAN
CONTROL
CIRCUIT
BY-PASS FLOW
CONTROL DEVI CE
CIRC U IT
THERMAL FUSE
OVER HEAT
SWITCH
MODULATING
SOLENOID
VALVE
DC40V
DC5V
A B C
SG
SWITCHING
POWER SUPPLY
THERMISTOR
CIRCUIT
B
SG
RELAY 1
A
WATER FL OW
SENSOR
CIRC U IT
WATER FL OW
CONTROL DEVI CE
CIRC U IT
A
SG
A
SG
SG
A
QS
SG
FR
FLAME
DETECTING
CIRCUIT
FLAME ROD
GND
SG
A
REMOTE
CONTROLLER
CIRCUIT
A B
E
PG
A BC
SG
SG
B
VARISTOR
ARRESTER
GND
SG
WATER FLOW
SENSOR
WATER FLOW
CONTROL DEVI CE
BY-PASS FLOW
CONTROL DEVI CE
M
M
DC12V
DC170V
D
E
PG
SV3
SV2
SV1
SV0
RELAY
DRIVING
CIRCUI T
D
BY-PASS SERVO MODEL ONLY
OUTGOING WATER
THERMISTOR
HEAT EXCHANGER
THERMISTOR
AIR TEMPERATURE
THERMISTOR
INDOOR MODEL ONLY
MODULATING
VALVE POWER
CONTROL
CIRC U IT
Figure 41. Ladder Diagram.