Greenheck IAQ-42 (467954) - Manual (Page 6)

IAQ-42 Trouble Shooting Guide
IMPORTANT: The LED on top of the IAQ-42’s controller will flash 1 time per second when it is receiving all of
the proper inputs. If the LED is flashing more than once per second there is an alarm condition that must be
corrected. Verify that all of the connections are made per the setup and operation instructions.
Symptom Possible Cause Corrective Action
The damper doesn’t respond to
position or airflow commands and
remains closed. The controller LED
is not lit at all.
There is no power to the control
box.
Apply 120 VAC across the input
power terminals as shown in
figure 1.
The transformer has been
damaged.
Using a volt meter, check the
voltage across control box
terminals 1 and 2. If it is not
approximately 24 VAC the
transformer may have been
damaged. Contact the factory.
The control box has been
damaged.
Contact the factory.
The damper doesn’t respond to
position or airflow commands and
remains closed, but the controller
LED flashes at the proper 1 time
per second.
The actuator is not getting power
or is damaged.
Send a 10 Vdc signal to the flow/
position command. Check that
there is approximately 24 VAC
across control box terminals 1 and
2 and approximately 10 Vdc across
control box terminals 6 and 7. If
the proper voltage is being applied
and the actuator does not move
from the closed position it may be
damaged. Contact the factory.
The damper responds to changes
in airflow command signal, but
the airflow through the damper is
believed to be incorrect. The LED
flashes at the proper 1 time per
second.
The high-pressure pickup is not
properly plumed back to the
control box or there is a leak in the
line.
Make sure that the pneumatic
bulkhead fitting coming out of the
damper labeled “high pressure” is
plumbed back to the pneumatic
fitting in the control box labeled
“high pressure”. Check the line for
leaks. Make sure that pneumatic
lines inside the damper are
properly connected.
One or more of the pressure pick-
up mounted on the upstream side
of the damper are plugged.
Disconnect the pneumatic line
running back to the controller and
run high-pressure air through the
pin holes in the blade air pressure
pick-ups. Reconnect the pneumatic
line running to the controller.
The honeycomb airflow
straightener is damaged.
Replace the airflow straightener
One or more of the pressure pick-
ups has been bent or damaged. Replace the damaged pressure
pick-up(s). Contact the factory.
6