1. Complete housing base and cover assembly.
2. Two #10 sheet metal mounting screws.
3. Two sampling tube filters.
4. One test magnet.
5. Drilling template.
6. Two 5/16-inch O-rings.
7. Two rubber tube bushings seals.
8. Four #6 self-tapping mounting screws for the sampling tube.
9. One filter adapter.
10.One inlet tube end plug.
11.Four #6x7/10 cover mounting screws.
11.Two #10 speed nuts.
Note 1:The inlet sampling tube must be ordered separately. It must be the correct length for the width of the duct
where it will be installed. See Table 1 to determine the inlet tube required for different duct widths. Smoke
detector heads (CPX-551, ionization; SDX-551, photoelectronic) must be ordered separately.
WARNING
LIMITATIONS OF DUCT DETECTORS
The National Fire Protection Association has established that DUCT DETECTORS MUST NOT BE USED AS A
SUBSTITUTE FOR OPEN AREA DETECTOR PROTECTION as a means of providing life safety. Nor are they a
substitute for early warning in a building’s regular fire detection system.
Notifier supports this position and strongly recommends that the user read NFPA Standards 90A, 72, and 101. The
DHX-502 is listed per CAN/ULC-S529.
WARNING: This device will not operate without electrical power. Frequently, fire situations may cause an
interruption of power to the detector. The system safeguards should be discussed with your local fire
protection specialist.
WARNING: This device will not sense smoke unless the ventilation system is operating.
WARNING: In order to function properly, this detector must be installed according to these instructions. Do not
exceed the electrical or ambient specifications or the detector will not function properly. This detector
must be protected from the elements.
INSTALLATION SEQUENCE
PAGE
Step 1. Verify duct air flow direction and velocity .......................................................................................................... 2
Step 2. Drill the mounting holes ...................................................................................................................................... 3
Step 3. Secure the housing base to the duct ................................................................................................................. 3
Step 4. Install the inlet sampling tube ............................................................................................................................ 3
Step 5. Field wiring .......................................................................................................................................................... 5
Step 6. Install the filters and check pressure differential .............................................................................................. 5
Step 7. Perform detector check ...................................................................................................................................... 7
Step 8. Install the cover ................................................................................................................................................... 8
Step 9. Perform the final system check (Testing) .......................................................................................................... 8
STEP 1. VERIFY DUCT AIR FLOW DIRECTION AND VELOCITY
The DHX-502 is designed to be used in air handling systems having air velocities of 500 to 4000 feet per minute. Be
sure to check engineering specifications to ensure that the air velocity in the duct falls within these parameters. If
necessary, a velocity meter to check the air velocity in the duct.
N500-04-00
2
I56-507-06
N500-04-00
11
I56-507-06
NOTES
