Installation Guide

27
8. TROUBLESHOOTING (CONT’D)
PROBLEMS POSSIBLE CAUSES YOU SOULD TRY THIS
7
The damper system
does not work
(LED flashes AMBER,
error code E23).
At power up, no RED LED. • See point 4.
At power up, LED lights RED and
there is a clicking sound coming
from electrical compartment, but
damper does not move:
• Ice or other things hindering the
damper movement.
• J12 unconnected or bad contact.
• Wrong connection of J8.
• The transformer may be defective
(no 24 VAC between J8-1 and J8-2).
• The damper actuator
may be defective.
• Remove ice or hindering elements.
• Check J12 connection (both harness side and board side).
• Check J8 connection.
• With unit powered and J9 connected, check if there is about
20-24 VAC between J8-1 and J8-2 (BROWN wires)
transformer connector. If no, change the transformer.
• Erase the error code by pressing on MODE and %HUM
keys for 10 sec., then set the unit in CONT and check if the
error code is displayed again.
• If the error code is back, replace the damper system.
Damper moves but does not stop
when supposed to:
• Bad connection of J12 connector.
• Damper system PCB defective or
damper motor stripped gear.
• The main PCB is defective.
• Check J12 connection (both harness side and board side).
• Replace the damper system.
• Replace the main PCB.
8
A. The supply motor does
not work, but exhaust
motor works.
(LED flashes RED, error
code E25)
B. The exhaust motor does
not work, but supply
motor works.
(LED flashes RED, error
code E26)
• The supply motor may be defective
or blocked by an obstacle.
• The exhaust motor may be defective
or blocked by ice or an obstacle..
• Make sure that there is no obstacle blocking the motor.
• Check the connection of J4 and J15 connectors.
• Jump the OL and OC terminals and plug supply motor to
J5 connector and exhaust motor to J4 connector. If the
supply motor works but the exhaust motor does not, replace
the main PCB. If the supply motor is still not working, plug
back supply motor to J4 connector and exhaust motor to J5
connector and continue to investigate.
• Swap both motor control cable connections on PCB:
connect supply control cable to J17 connector and exhaust
control cable to J15 connector. If the supply motor works
but the exhaust motor does not, replace the main PCB. If
the supply motor is still not working, plug back the exhaust
control cable to J17 connector and replace the supply motor.
• Make sure that there is no obstacle or ice blocking the
motor.
• Check the connection of J5 and J17 connectors.
• Jump the OL and OC terminals and plug exhaust motor
to J4 connector and supply motor to J5 connector. If
the exhaust motor works but the supply motor does
not, replace the main PCB. If the exhaust motor
is still not working, plug back exhaust motor to J5 connector
and supply motor to J4 connector and continue to investigate.
• Swap both motor control cable connections on PCB: connect
exhaust control cable to J15 connector and supply control
cable to J17 connector. If the exhaust motor works but the
supply motor does not, replace the main PCB. If the exhaust
motor is still not working, plug back the supply control cable
to J15 connector and replace the exhaust motor.
9
Unit works on CONT and
TURBO modes, but not in
RECIRC mode.
• Reversed motor connections. • Swap both motor power cable connections J4 and J5 on
PCB. Check for the supply motor (on right side of the unit)
operation in RECIRC mode.
• If the exhaust motor is still running in RECIRC mode instead
of supply, connect back in place power cable connections
J4 and J5 on PCB and swap control cables J15 and J17 on
PCB.
• If the problem is not solved, change the PCB.