Carrier 50TCQ 04 Series Service And Maintenance Instructions page 37

1. Disconnect power from the duct detector then remove
the sensor's cover. See Fig. 54.
2. Using a vacuum cleaner, clean compressed air, or a
soft bristle brush, remove loose dirt and debris from
inside the sensor housing and cover. Use isopropyl
alcohol and a lint−free cloth to remove dirt and other
contaminants from the gasket on the sensor's cover.
3. Squeeze the retainer clips on both sides of the optic
housing then lift the housing away from the printed
circuit board.
4. Gently remove dirt and debris from around the optic
plate and inside the optic housing.
5. Replace the optic housing and sensor cover.
6. Connect power to the duct detector then perform a
sensor alarm test.
Sampling
tube
Airflow
Fig. 54 − Sensor Cleaning Diagram
Indicators
Normal State:
The smoke detector operates in the normal state in the
absence of any trouble conditions and when its sensing
chamber is free of smoke. In the normal state, the Power
LED on both the sensor and the controller are on and all
other LEDs are off.
Alarm State:
The smoke detector enters the alarm state when the
amount of smoke particulate in the sensor's sensing
chamber exceeds the alarm threshold value. See Table 12.
Upon entering the alarm state:
S The sensor's Alarm LED and the controller's Alarm
LED turn on.
S The contacts on the controller's two auxiliary relays
switch positions.
S The contacts on the controller's alarm initiation relay
close.
S The controller's remote alarm LED output is activated
(turned on).
S The controller's high impedance multiple fan shutdown
control line is pulled to ground Trouble state.
The SuperDuct duct smoke detector enters the trouble
state under the following conditions:
S A sensor's cover is removed and 20 minutes pass before
it is properly secured.
S A sensor's environmental compensation limit is reached
(100% dirty).
S A wiring fault between a sensor and the controller is
detected.
An internal sensor fault is detected upon entering the
trouble state:
S The contacts on the controller's supervisory relay
switch positions. See Fig. 55.
S If a sensor trouble, the sensor's Trouble LED and the
controller 's Trouble LED turn on.
S If 100% dirty, the sensor's Dirty LED turns on and the
controller 's Trouble LED flashes continuously.
S If a wiring fault between a sensor and the controller, the
controller 's Trouble LED turns on but not the sensor's.
Alarm
HVAC duct
Sensor
housing
Optic
plate
Retainer
clip
Optic
NOTE: All troubles are latched by the duct smoke
housing
detector. The trouble condition must be cleared and then
C07305 the duct smoke detector must be reset in order to restore it
to the normal state.
Resetting Alarm and Trouble Condition Trips
Manual reset is required to restore smoke detector systems
to Normal operation. For installations using two sensors,
the duct smoke detector does not differentiate which
sensor signals an alarm or trouble condition. Check each
sensor for Alarm or Trouble status (indicated by LED).
Clear the condition that has generated the trip at this
sensor. Then reset the sensor by pressing and holding the
reset button (on the side) for 2 seconds. Verify that the
sensor's Alarm and Trouble LEDs are now off. At the
controller, clear its Alarm or Trouble state by pressing and
holding the manual reset button (on the front cover) for 2
seconds. Verify that the controller's Alarm and Trouble
LEDs are now off. Replace all panels.
Troubleshooting
Controller's Trouble LED is On:
1. Check the Trouble LED on each sensor connected to
the controller. If a sensor's Trouble LED is on,
determine the cause and make the necessary repairs.
2. Check the wiring between the sensor and the
controller. If wiring is loose or missing, repair or
replace as required.
Controller's Trouble LED is Flashing:
1. One or both of the sensors is 100% dirty.
2. Determine which Dirty LED is flashing then clean
that sensor assembly as described in the detector
cleaning section.
37
Fig. 55 − Controller Assembly
Trouble
Power
Test/reset
switch
C07298