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Fire Alarm Systems | D342 Four‑wire Duct Smoke Detector Housings
D342 Four‑wire Duct Smoke Detector
Housings
www.boschsecurity.com
u For 1 ft (30.5cm) to 10 ft (3 m) ducts with air
velocity between 300 ft/min to 4000 ft/min
(1.52 m/s to 20.3 m/s)
The D342 Duct Smoke Detector Housings mount on
the ducts of heating, ventilation, and air conditioning
(HVAC) systems to monitor the presence of smoke in
the conditioned air. The housing works with all 24 VDC
or 24 VAC, 220 VAC, or 240 VAC UL Listed four‑wire
control panels.
The efficient housing design samples the air passing
through a duct and detects potentially hazardous
conditions. When smoke is detected, the detector
sends an alarm signal to the control panel or HVAC
control equipment that initiates the necessary action
to control air handling systems.
Functions
Alarm and Trouble Indication
A D344‑RT Remote Test Kit, a D344‑RL Remote
Indicator Kit, or a DRA‑5 Remote Annunciator can
provide remote LED indication of alarm and trouble
status. The red LED lights for an alarm. An open loop
causes the yellow Trouble LED to light.
Air Sampling
Use the duct detector housings in air handling systems
with ducts between 1 ft (30.5 cm) and 10 ft (3.05 m)
wide and air velocities between 300 ft/min and
u Easy duct tube installation through the housing cuts
installation time.
u Detector test and reset without removing covers
u Clear cover allows quick visual inspection
u Tube filters, dust immune smoke detector, and easy
disassembly for cleaning reduce maintenance time
and cost
4000 ft/min (1.52 m/s to 20.3 m/s). Air is forced into
the detector through an air sampling tube, tested, and
returned to the duct through an exhaust tube
(supplied).
Sampling tubes should extend across the width of the
duct. Bosch Security Systems, Inc. offers sampling
tubes in three different sizes. Combined or cut the
tubes to make other lengths. Sampling tubes over 3 ft
(91.4 cm) must be supported at the end opposite the
duct detector. Sampling tubes are provided with an
end plug that must be installed in the open end.
System Testing
Place an external magnet on the detector housing or
switch a signal from a remote test station to test the
system (requires an external 24 V supply).
Reset the system by power shutdown or if a D344‑RT
is connected, use the key-operated switch.
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2 | D342 Four‑wire Duct Smoke Detector Housings
Certifications and approvals
Region Certification
USA UL UROX: Smoke-Automatic Fire Detectors
CSFM see our website
Hong Kong HKFSD J-500/C/030
(ANSI/UL 268) and UROX7: Smoke-Automatic Fire Detectors Certified for Canada (CAN/ULC-S529)
Installation/configuration notes
Compatible Products
The following products are compatible with the D342
Family Four‑wire Duct Smoke Detector Housings:
Category Product ID Product Description
Control Panels Works with all 24 VDC or VAC, 220 VAC, or 240 VAC
Detector
Heads
Remote
Annunciators
D344‑RT Remote test kit
DRA‑5 Remote annunciator (5 VDC)
UL Listed control panels
D285‑DH Photoelectric duct smoke detector
head
D344‑RL Remote indicator kit
Remote Indicators
NFPA 72 requires detectors have remote alarm
indicators where duct smoke detectors are installed in
concealed locations, where the detector is more than
10 ft (3 m) above the floor, or where the detector's
alarm indicator is not visible to responding personnel.
The optional D344‑RT Remote Test Kit, D344‑RL
Remote Indicator Kit, or DRA‑5 Remote Annunciator
can be used to satisfy this requirement.
Power Considerations
The detector housing provides one primary power
source of 24 VDC, 24 VAC, 220 VAC, or 240 VAC. Do
not connect a high‑voltage AC source and a
low‑voltage AC/DC source to the same housing.
Parts included
The D342 Four‑wire Duct Smoke Detector Housing
comes with:
Quant. Component
1 D342 Duct Detector Housing
1 Exhaust tube
1 Cover gasket
2 Tube clamps with four screws
2 Foam gaskets
2 Air filters
1 Drilling template
1 Hardware pack
1 Literature pack
The D342P Duct Photoelectric Smoke Detector Kit
comes with all components supplied with the D342
plus:
Quant. Component
1 D285DH Photoelectric Duct Smoke Detector Head
1 D344‑1.5 Sampling Tube
Technical specifications
Electrical
Current (operating): 24 VDC: 65 mA maximum ; 24 VAC: 200 mA
Voltage (operating): 24 VDC, 24 VAC, 220 VAC, or 240 VAC
maximum ;
220 VAC: 30 mA maximum ; 240 VAC: 30 mA
maximum
Environmental
Relative Humidity: Up to 93% non‑condensing
Temperature
(operating):
+32°F to +120°F (0°C to +49°C)
Mechanical
Dimensions
(H x W x D):
Material: High‑impact fire‑retardant polymer plastic
Weight (housing
only):
6.5 in. x 15.5 in. x 4.25 in. (16.5 cm x 39.5 cm
x 11 cm)
3.75 lb (1.7 kg)
Outputs
Alarm: Form A, normally‑open (NO) contacts rated
Auxiliary: Two Form C contacts rated for 10 A at
Trouble: Form A, normally‑closed (NC) contacts rated
for 0.5 A at 24 VDC or VAC and for 0.1 A at
220 VAC or 240 VAC
24 VDC, 24 VAC, 220 VAC, or 240 VAC
for 0.5 A at 24 VDC or VAC and for 0.1 A at
220 VAC or 240 VAC
Ordering information
D342 Duct Detector Housing
Duct detector housing with an exhaust tube, two tube
clamps with screws, one cover and two foam gaskets,
two air filters, a drilling template, installation
instructions and mounting hardware.
Order number D342