24
DETECTOR CLEANING
Cleaning the Smoke Detector
Clean the duct smoke sensor when the Dirty LED is flashing
continuously or sooner, if conditions warrant.
1. Disconnect power from the duct detector then remove the
sensor’s cover. (See Fig. 32.)
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 hous-
ing, 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.
Fig. 32 — 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 sen-
sor 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 3.)
Upon entering the alarm state:
• The sensor’s Alarm LED and the controller’s Alarm LED
turn on.
• The contacts on the controller’s two auxiliary relays switch
positions.
• The contacts on the controller’s alarm initiation relay
close.
• The controller’s remote alarm LED output is activated
(turned on).
• 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 un-
der the following conditions:
• A sensor’s cover is removed and 20 minutes pass before it
is properly secured.
• A sensor’s environmental compensation limit is reached
(100% dirty).
• A wiring fault between a sensor and the controller is detected.
An internal sensor fault is detected upon entering the trouble
state:
• The contacts on the controller’s supervisory relay switch
positions. (See Fig. 33.)
• If a sensor trouble, the sensor’s Trouble LED the control-
ler’s Trouble LED turn on.
• If 100% dirty, the sensor’s Dirty LED turns on and the
controller’s Trouble LED flashes continuously.
• If a wiring fault between a sensor and the controller, the
controller’s Trouble LED turns on but not the sensor’s
Trouble LED.
Fig. 33 — Controller Assembly
NOTE: All troubles are latched by the duct smoke detector. The
trouble condition must be cleared and then the duct smoke detec-
tor 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 press-
ing and holding the reset button (on the side) for 2 seconds.
Table 3 — Detector Indicators
CONTROL
OR
INDICATOR
DESCRIPTION
Magnetic
test/reset
switch
Resets the sensor when it is in the alarm or trouble
state. Activates or tests the sensor when it is in the
normal state.
Alarm LED Indicates the sensor is in the alarm state.
Trouble LED Indicates the sensor is in the trouble state.
Dirty LED
Indicates the amount of environmental compensation
used by the sensor (flashing continuously = 100%)
Power LED Indicates the sensor is energized.
CAUTION
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in personnel and
authority concern.
If the smoke detector is connected to a fire alarm system, first
notify the proper authorities that the detector is undergoing
maintenance then disable the relevant circuit to avoid
generating a false alarm.
HVAC DUCT
SAMPLING
TUBE
RETAINER
CLIP
OPTIC
PLATE
OPTIC
HOUSING
SENSOR
HOUSING
AIRFLOW
ALARM
POWER
TEST/RESET
SWITCH
TROUBLE
RESET
ALARM
TROUBLE
POWER
To Next Page
Loading...
