Duct Smoke Detector Testing and Maintenance

InnovairFlex™ Testing and Maintenance
Duct Smoke Detector Testing
and Maintenance Guide
Testing and maintenance is important to any duct smoke detector application.
This document will provide details on proper duct smoke detector testing and
maintenance as well as NFPA recommendations.
NFPA Recommendations
• S
ystem Sensor strongly recommends that the user read NFPA Standards 90A,
72, and 101. The D4120 Air Duct Smoke Detectors are listed per UL 268A.
• P
er NFPA it is recommended that duct smoke detectors be visually inspected
twice a year and functionally tested once a year..
Measurement Testing
• The D4120 is designed to operate over an extended air speed range of 100
to 4000 FPM. To verify sufficient sampling of ducted air, turn the air handler
on and use a manometer to measure the differential pressure between the
two sampling tubes. The differential pressure should measure between 0.01
and 1.11 inches of water. Most commercially available manometers cannot
accurately measure pressure differentials with less than 500 FPM of air
speed. These applications may require one of the following: 1) the use of a
current-sourcing pressure transmitter, or 2) the use of aerosol smoke.
ow Flow Air Flow Test Using Dwyer Series 607
Differential Pressure Transmitter
1. V
erify the air speed of the duct using an
anemometer. Air speed must be at least 100 FPM.
2. U
sing Dwyer Series 607 connect the leads of the
meter to either side of the1000Ω resistor.
3. Allow unit to warm up for 15 seconds.
4. W
ith both HIGH and LOW pressure ports open
to ambient air, measure and record the voltage drop
across the 1000Ω resistor (measurement 1), 4.00 volts is typical.
5. U
sing flexible tubing and rubber stoppers, connect the HIGH side of the
transmitter to the sampling tube of the duct smoke detector housing, and
the LOW side of the transmitter to the exhaust tube of the duct smoke
detector housing.
6. M
easure and record the voltage drop across the 1000Ω resistor
(measurement 2).
7. S
ubtract the voltage recorded in measurement 1 from the voltage
recorded in measurement 2.
8. If the difference is greater than 0.15 volts, there is enough air flow through
the duct smoke detector for proper operation.
w w w. sys te m s e n s o r. c o m / fl ex
HVFL18401 • 12/12
Alarm Testing Procedures
• Test/Reset Button - Press and hold the test button located on
the power board cover for at least 2 seconds.
• M
02-04-00 Magnet Test - Place the painted surface of the
magnet onto the MAGNET TEST location on the sensor
cover of unit. Or use Remote Test Accessory including
RTS151, RTS151KEY, RTS2 and RTS2-AOS.
• D
uring testing the red alarm LED on the sensor and the
power board should latch on, as should any accessories
(RA100Z, RTS151). Verify system control panel alarm
status and control panel execution of all intended auxiliary
−− The detector must be reset by the system control panel,
front cover Test/Reset button, or remote accessory.
−− To reset using the Test/Reset button on the power board
cover simply press and release.
Smoke Response Tests
• To determine if smoke is capable of entering the sensing
chamber, visually identify any obstructions. Plug the exhaust
and sampling tube holes to prevent ducted air from carrying
smoke away from the detector head, then blow smoke such
as cigarette, cotton wick, or punk directly at the head to
cause an alarm. Remember to remove the plugs after this
test, or the detector will not function properly.
Smoke Entry Using Aerosol Smoke
• This test is intended for low-flow systems (100-500 FPM). If
the air speed is greater than 500 FPM, use a conventional
manometer to measure differential pressure between the
sampling tubes, as described in Section 7.1.
• D
rill a ¼ inch hole 3 feet upstream from the duct smoke
detector. With the air handler on, measure the air velocity
with an anemometer. Air speed must be at least 100 FPM.
Spray aerosol smoke* into the duct through the ¼ inch
hole for five seconds. Wait two minutes for the duct smoke
detector to alarm. If the duct smoke detector alarms, air
is flowing through the detector. Remove the duct smoke
detector cover and blow out the residual aerosol smoke from
the chamber and reset the duct smoke detector. Use duct
tape to seal the aerosol smoke entry hole.
* Aerosol smoke can be purchased from Home Safeguard Industries at
homesafeguard.com, model 25S Smoke Detector Tester, and Chekkit
Smoke Detector Tester model CHEK02 and CHEK06 available from
SDi. When used properly, the canned smoke agent will cause the
smoke detector to go into alarm. Refer to the manufacturer’s published
instructions for proper use of the canned smoke agent.
Maintenance Procdeures
• Canned aerosol simulated smoke (canned smoke agent)
formulas will vary by manufacturer. Misuse or overuse to
these products may have long term ad­verse effects on the
smoke detector. Consult the canned smoke agent manufac­
turer’s published instructions for any further warnings or
caution statements.
• N
otify the proper authorities that the smoke detector system
is undergoing maintenance, and that the system will
temporarily be out of service. Disable the zone or system
undergoing maintenance to prevent unwanted alarms and
possible dispatch of the fire department.
1. Remove the sensor to be cleaned from the system.
2. R
emove the sensor cover by pulling outward on each
of the four removal tabs that hold the cover in place.
3. V
acuum the screen carefully without removing it. If further
cleaning is required continue with Step 4, otherwise skip
to Step 7.
4. R
emove the chamber cover/screen assembly by pulling
it straight out.
5. U
se a vacuum cleaner or compressed air to remove dust
and debris from the sensing chamber.
6. R
einstall the chamber cover/screen assembly by sliding
the edge over the sensing chamber. Turn until it is firmly
in place.
7. R
eplace the cover using the holes for the LEDs for
alignment and then gently pushing it until it locks
into place.
8. Reinstall the detector.
9. Restore system power.
10. Perform Detector Check
11. Notify the proper authorities testing has been completed
and the smoke detector system is back in operation.
* Note: If any unitary packaged air conditioning units are run during
the drywall installation phase of any building under construction to
accelerate the drying of joint compound, the subsequent sanding
of those drywall joints and resulting dust may compromise the
sensor heads in duct smoke detectors. To avoid this condition it
is recommended that the sensor heads be removed during the
construction phase.
©2012 System Sensor. HVFL18401 • 12/12