Duct Detector Troubleshooting | SL-2000 duct detector wiring |Detectors tech support
Learn how to troubleshoot a smoke duct detector. Smoke detector wiring and interconnecting. Remote controls compatibility.
A Halma Company.
⇒ INTERCONNECT WIRING
Watch this video to see how to connect two SL-2000 duct smoke detectors together:
⇒ FIRE ALARM WIRING
Watch this video to see how to connect a SL-2000 duct smoke detector to a fire alarm control panel:
⇒ RESIDENTIAL FURNACE WIRING
Some newer furnaces will continue to run the fan after call for heat signal is broken sometimes called a fan run-down, this can sometimes be programmed via DIP switches on the furnace board. Use below configurations where it is unable to be turned off.
⇒ REMOTE ANNUNCIATOR WIRING
Reminder LED indicators on MS series remotes are polarity sensitive, always ensure the black wire is connected to terminal 19.
Please note LED indicators on MS series remotes are polarity sensitive, always ensure the black wire is connected to terminal 19.
Troubleshoot with these steps:
Check power is good, probe across terminals 9 and 10, check for roughly 24V.
Check detector head is seated, rotate counterclockwise and reattach it by turning clockwise until its seated.
Check transparent lid, ensure it is fitted and not ajar and all screws are tightened, SW1 can be inspected for damage if the lid has been installed incorrectly previously.
Duct smoke detectors can be mounted any way either vertically or horizontally if the sampling tube holes are facing the direction of airflow.
NFPA72 recommends all sampling tubes to be at least 80% of the duct width i.e. if your duct is 12 inches wide, the sampling tube must be at least 9.6 inches long.
Any tube over 3ft must be supported.
Tubes can be cut down for the correct size, but metal tubes have different hole spacing based on its size.
The 10inch tube has holes spaced closer together than a 5 ft tube. Therefore, you cannot cut a longer tube shorter than its recommended duct size or there will not be a correct amount of air sampled from the duct work.
Recommended procedure is removing detector head and running on external 24V power supply and detector base using an SDI Trutest 801 for testing sensitivity.
check the detector head and housing for excessive dust. Detectors can be blown out with compressed air or replacement detector heads ordered, 55000-328 for -P model or 55000-225 for the -N model.
This can be checked by looking to see if there are wires on terminals 12 and 20, check to see if the other detector is maybe in alarm.
If detector has been wired to a remote or accessories remove wiring such that only power is connected, if it stops going into alarm confirm correct wiring for model of remote when reattaching and that key switch is not activated.
In situations of high humidity or temperature swings such as in sunbelt states condensation can build up on and inside detectors which can cause false alarms, we recommend moving a detector further downstream on ductwork or inside building where temperature swings might not be as extreme.
If detector still goes into alarm when all wiring removed, replace detector head or RMA unit.
For RMA request click here: RMA request.
Alarm contact terminals 16 and 6 (normally closed and common) can be used to break the red 24V power wire to the thermostat.
16 and 6 effectively works as a switch, in a normal condition 16 is connected to 6 and when in alarm 16 is disconnected from 6.
Some residential furnaces have a fan rundown mode where the fan will run even after a signal from the thermostat, these furnaces sometimes have a DIL switch to program this feature or alternatively power can be broken to the furnace alternate to the thermostat by breaking the neutral power to the furnace through terminals 16 and 6.
See Wiring diagrams here: Wiring Diagrams
Breaking same power used to power detector when in alarm. Use a separate 24VAC transformer, power supply or mains power.
MSR50/100 based remotes wire to SL2000.
If wiring is correct, check for shorted or open circuit wires pulled from detector to the remote. Multimeter can be used to continuity test wires if disconnected from detector and remote and twisted together in pairs.
Air product and controls duct smoke detectors are not compatible, or UL listed to work with System Sensor or other manufacturer’s remotes.
Please see here our remotes compatibility info: Remotes
SL2000 terminals 12 and 20 must be connected between all detectors desired to be interconnected, a common power source must be used such that all detectors interconnected must be powered from a common 24VAC transformer, or mains power circuit.
For a common remote for common test/reset, 12 and 20 must be connected between all desired detectors.
In a typical class B fire alarm configuration wire one wire from your fire alarm panel to terminal 13 and the other to 14. Make a wire jumper from terminal 13 to terminal 5 and place your end of line resistor to terminals 14 and 15.
For applications of multiple duct smoke detectors on a single fire alarm circuit, all alarm contacts must be wired to the panel in parallel with all trouble contacts wired in series with the end of line resistor on the very last detector. Refer to Page 4 of the installation guide for wiring diagram.
Normally open and common relay contacts on the fire alarm interface can be connected to terminals 1 and 20 on the SL2000 duct smoke detector.
Correct airflow can be confirmed with the use of a magnehelic differential pressure gauge between the sampling and exhaust tubes of the detector, a reading between 0.01 and 1.2 inches of water verifies enough airflow.
The detector head can be tested for correct operation by spraying TG-2000 test gas into the test port of the detector, an alarm would be expected. Continued testing also includes using the included test magnet on the top of the duct smoke detector housing between the 2 marked lines indicated on lid, again an alarm would be expected to confirm correct operation.
The detector control board and relays can be tested for correct operation by pressing the black test/reset button in the transparent lid hole, an alarm condition would verify correct operation (red LED on board).
See video here: VIDEO needs to be linked