SS-400-000
5
I56-3065-000R
2. To determine that smoke is capable of entering the sensing
chamber, a visual examination should be conducted to note
any obscurations around the sensing chamber. If a smoke test is
required, smoke such as cigarette, cotton wick, or punk smoke
may be blown directly at the smoke detector head. It is im-
portant to plug the exhaust and sampling tube hole to prevent
ducted air from blowing smoke away from the smoke detector
head. Record all test records in the Detector Test Log (page 8).
CAUTION
Remember to remove the plugs after this test or the detector will
not sense smoke in the air duct.
Figure 6. Sampling tube filter installation:
SAMPLING TUBE
FILTERS
SAMPLING TUBE
MOUNTING
SCREWS
DETECTOR HEAD
EXHAUST
FILTER ADAPTER
DETECTOR BASE
INLET SAMPLING TUBE
FOAM GASKET
H0548-00
8.2 Alarm Tests
Before replacing the duct housing cover, the detector intercon-
nections should be checked. The 7251DH may be checked as
follows:
A. M02-04-00 Magnet Test
1. Make sure power is applied to the detector.
2. Place the painted surface of the test magnet against the
housing next to the indentation molded onto the outside of
the housing (see Figure 7).
3. The LEDs on the detector should latch on as should any ac-
cessories (i.e. RA400ZA, RTS451), and the alarm condition
should be verified at the control panel.
Figure 7. Testing detector
INDENTATION
TEST
MAGNET
PAINTED SIDE
TOWARD HOUSING
DUCT
DETECTOR
HOUSING
DETECTOR
HEAD
H0579-00
Figure 8. Detector head removal:
TWIST
COUNTERCLOCKWISE
TO REMOVE
DUCT
HOUSING
TWIST
CLOCKWISE
TO INSTALL
DETECTOR
HEAD
H0546-00
B. RTS451/RTS451KEY Remote Test Station
The RTS451/RTS451KEY Remote Test Station facilitates test of the
alarm capability of the duct smoke detector as indicated in the
RTS451/RTS451KEY manual. The 7251DH duct detector cannot be
reset by the RTS451/RTS451KEY. It must be reset at the system control
panel.
To install the RTS451/RTS451KEY test coil, connect the device as
shown in Figure 11; wire runs must be limited to 25 ohms or less
per interconnecting wire. Place the coil in the detector housing
with the arrow facing up and pointing toward the detector as in
Figure 11. Attach the coil leads to the housing terminals as shown;
polarity is not important. Firmly screw the bracket in place over
the test coil.
8.4 Trouble Test
The capability of “TROUBLE” detection is tested by removing
the detector head from the duct housing. The detector head is
removed by turning it counterclockwise about 10 degrees (Figure
8). The system control panel should indicate a trouble condition.
Reinserting the detector head should clear the trouble condition.
Step 9. Install the Cover
Install the cover using the four screws. Be certain filters are in-
stalled as specified in Step 7. Make sure that the cover fits into
the base groove and that all gaskets are in their proper positions.
Tighten the four cover screws to 10 in/lbs.
Step 10. Perform the Final System Check
Place the magnet in position as shown in Figure 7. The LEDs on
the detector should light. Any accessory LED(s) will also light.
The system control panel should indicate an alarm condition.
Periodic Maintenance Requirements
Air duct smoke detectors should be maintained at least once a
year. They should be maintained more often if the detector heads
become obviously dirty in less than a year. The detectors must
also be cleaned immediately after a fire (see cleaning section on
Page 7). Failure to properly maintain air duct smoke detectors may
cause unnecessary false alarms.
It is recommended that a permanent Detector Test Log be set up
and maintained, with a record for each individual smoke detector
in each building. Each detector should be clearly described, with
information on the type of detector, the model number, the serial
number (if any), the location, and the type of environment. Data
entries should include test dates, type of test mode, test results,
maintenance, and comments. A detector test log is included in
this manual.
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