Greenheck IAQ-42 (467954) - Manual (Page 7)

7
Trouble Shooting Guide cont....
The damper is wide open all the
time regardless of the requested
flow, but the LED flashes at the
proper 1 time per second.
The low-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 “low pressure” is
plumbed back to the pneumatic
fitting in the control box labeled
“low pressure”. Check the line for
leaks. Make sure that pneumatic
lines inside the damper are
properly connected.
The pressure pick-up mounted on
the downstream 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 high-pressure and low-
pressure pick-ups are plumbed
backwards.
Make sure that the pneumatic
fitting mounted upstream of the
damper runs back to the pressure
transducer port labeled “High” and
that the pneumatic fitting mounted
downstream of the damper runs
back to the pressure transducer
port labeled “Low”.
The damper is mounted
backwards. The honeycomb or louver must be
facing upstream.
The damper is wide open all the
time regardless of the requested
flow. The controller LED flashes
more than once per second.
The actuator position feedback is
not wired or is reporting incorrectly.
Make sure actuator terminal 5 is
wired back to control box terminal
8. Using a volt meter, check
the voltage across control box
terminals 8 and 2. It should be near
10Vdc (because the damper is wide
open). If not contact the factory.
The pressure transducer has been
damaged or disconnected.
While air is going through the
damper, use a volt meter to check
the voltage across the pressure
transducer terminals labeled “-”
and “o”. It should be greater than
0 Vdc, but less than 10 Vdc. If not
contact the factory.
The damper doesn’t react to
position or airflow commands and
stays closed, but the controller
LED flashes at the proper 1 time
per second.
The actuator is slipping on the
extension pin/jackshaft.
Using a vice grip, close the
damper completely. Cut power to
the actuator. Retighten down the
actuator to the shaft.
The damper will close to a certain
point, but too much air is believed
to be moving through the damper.
The LED flashes at the proper 1
time per second.
The pressure transducer is seeing
more than 2.5” wc.
Verify by using a volt meter to
measure the voltage across the
pressure transducer terminals
labeled “-” and “0”. If the value is
greater than 10 Vdc the system
pressure is too high for the
transducer. Contact the factory.