Carrier 50HC Series Service And Maintenance Instructions

Also see for 50HC Series: Installation instructions Installation instructions

312. Verify that the test/reset station’s Trouble LEDflashes.Detector CleaningCleaning the Smoke DetectorClean the duct smoke sensor when the Dirty LED isflashing continuously or sooner if conditions warrant.OPERATIONAL TEST ALERTFailure to follow this ALERT can result in anunnecessary evacuation of the facility.If the smoke detector is connected to a fire alarmsystem, first notify the proper authorities that thedetector is undergoing maintenance then disable therelevant circuit to avoid generating a false alarm.NOTICE1. Disconnect power from the duct detector then removethe sensor’s cover. See Fig. 40.AirflowHVAC ductSamplingtubeRetainerclipOpticplateOptichousingSensorhousingC07305Fig. 40 -- Sensor Cleaning Diagram2. Using a vacuum cleaner, clean compressed air, or asoft bristle brush, remove loose dirt and debris frominside the sensor housing and cover.Use isopropyl alcohol and a lint--free cloth to removedirt and other contaminants from the gasket on thesensor’s cover.3. Squeeze the retainer clips on both sides of the optichousing.4. Lift the housing away from the printed circuit board.5. Gently remove dirt and debris from around the opticplate and inside the optic housing.6. Replace the optic housing and sensor cover.7. Connect power to the duct detector then perform asensor alarm test.IndicatorsNormal StateThe smoke detector operates in the normal state in theabsence of any trouble conditions and when its sensingchamber is free of smoke. In the normal state, the PowerLED on both the sensor and the controller are on and allother LEDs are off.Alarm StateThe smoke detector enters the alarm state when theamount of smoke particulate in the sensor’s sensingchamber exceeds the alarm threshold value. (See Table 8.)Upon entering the alarm state:S The sensor’s Alarm LED and the controller’s AlarmLED turn on.S The contacts on the controller’s two auxiliary relaysswitch positions.S The contacts on the controller’s alarm initiation relayclose.S The controller’s remote alarm LED output is activated(turned on).S The controller’s high impedance multiple fan shutdowncontrol line is pulled to ground Trouble state.The SuperDuct duct smoke detector enters the troublestate under the following conditions:S A sensor’s cover is removed and 20 minutes pass beforeit is properly secured.S A sensor’s environmental compensation limit is reached(100% dirty).S A wiring fault between a sensor and the controller isdetected.An internal sensor fault is detected upon entering thetrouble state:S The contacts on the controller’s supervisory relayswitch positions. (See Fig. 41.)S If a sensor trouble, the sensor’s Trouble LED thecontroller’s Trouble LED turn on.S If 100% dirty, the sensor’s Dirty LED turns on and thecontroller’s Trouble LED flashes continuously.S If a wiring fault between a sensor and the controller, thecontroller’s Trouble LED turns on but not the sensor’s.Alarm PowerTest/resetswitchTroubleC07298Fig. 41 -- Controller AssemblyNOTE: All troubles are latched by the duct smokedetector. The trouble condition must be cleared and thenthe duct smoke detector must be reset in order to restore itto the normal state.Resetting Alarm and Trouble Condition Trips:Manual reset is required to restore smoke detector systemsto Normal operation. For installations using two sensors,50HC