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7. Circuit board diagrams
Circuit
board
diagrams
and
check
points
(1)
Control
circuit
board
Signal interface
circuit board
During error status or
when the OA shutter is open: 0
Ω
During normal operation or
when the OA shutter is closed:
∞
Ω
When Lossnay is operating or
when After-heater is operating: 0
Ω
When Lossnay is stopped or
when After-heater is stopped:
∞
Ω
1s digit
10s digit
Fed with power: lit
Not fed with power: unlit
Remote controller
power supply indicator
(LED3 Green)
By-pass monitor output
Pre-heater output
(Between [7] and [10] )
During by-pass mode or
when the pre-heater is operating: 0
Ω
During heat exchange mode or
when the pre-heater is stopped:
∞
Ω
Malfunction monitor output
OA shutter output
(Between [8] and [10] )
Operation monitor output
After-heater output
(Between [9] and [10] )
Monitor output
COM
Controller
10 to 13 V DC
External control input
5 V DC (Insulated)
Power for the circuit
Fed with power: lit
Not fed with power: unlit
Not in use
Model selection
switch
Function selection
switch
Not in use
(or Not equipped)
Error indicator
(LED1 Green)
Normal: unlit
Error: blinking
During delay operation: lit
LED2
Red
Lit all the time
Power supply indicator
for the circuit
(LED4 Red)
Outdoor air (OA)
thermistor
Return air (RA)
thermistor
Circuit board name
Lot number indication
Indication of the
microcomputer
software No.
SA1
SA2
SW6
SW2
SW5
SW7
GND
(Insulated)
Power circuit board
12 to 14 V DC
(Insulated)
