System Sensor DNRA Installation And Maintenance Instructions Manual

WARNING

INSTALLATION AND MAINTENANCE INSTRUCTIONS

I56-3104-004

DNRA
Duct Smoke Detector

SPECIFICATIONS

Operating Temperature: –4° to 158° F (–20° to 70° C);
32° F to 120° F (0° C to 49° C) with module installed in the DNRA
Storage Temperature: –22° to 158° F (–30° to 70° C)
Humidity: 0% to 93% Relative Humidity Non-condensing
Air Velocity: 100 to 4000 ft./min. (0.5 to 20.3 m/sec.)
Rectangular Footprint Dimensions: 14.38 in L × 5 in W × 2.5 in D (37 cm L × 12.7 cm W × 6.36 cm D)
Square Footprint Dimensions: 7.75 in L × 9 in W × 2.5 in D (19.7 cm L × 22.9 cm W × 6.35 cm D)
Weight: 1.6 pounds; 0.73 kg
Electrical (See applicable detector head installation manual for electrical specifications. To determine applicable sensor head, use the Base/Sensor Cross Reference
chart at www.systemsensor.com (available on the Tools menu).

TABLE OF CONTENTS PAGE

[1] Limitations of Duct Smoke Detectors ................................................ 1

[2] General Description ......................................................................... 1

[3] Contents of the Duct Smoke Detector Kit .......................................... 1

[4] Detector Installation ....................................................................... 2

[6] Measurement Tests .......................................................................... 3

[7] Field Wiring; Installation Guidelines ................................................. 4

[8] Verification of Operation ................................................................. 4

[9] Cleaning ......................................................................................... 5

[10] Sensor Replacement ....................................................................... 5

[11] Optional Accessories ..................................................................... 5

Three-Year Limited Warranty .................................................................6

BEFORE INSTALLING

Read System Sensor’s Applications Guide for Duct Smoke Detectors (HVAG53),
which provides detailed information on detector spacing, placement,
zoning, wiring, and special applications. This manual is available online at
www.systemsensor.com. NFPA Standards 72, 90A and CAN/ULC-S524 should
also be referenced for detailed information.

NOTICE: This manual shall be left with the owner/user of this equipment.

IMPORTANT: This detector must be tested and maintained regularly follow­ing CAN/ULC-S524 requirements. The detector should be visually inspected
semiannually and functionally tested at least once a year. This may need to be
more frequent depending on the air quality of the duct supply air.

[1] LIMITATIONS OF DUCT SMOKE 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.

System Sensor supports this position and strongly recommends that the user
read NFPA Standards 90A, 72,101 and CAN/ULC-S524. The DNRA Air Duct
Smoke Detectors are ULC listed.

This device will not operate without electrical power. Fire situations may
cause an interruption of power. The system safeguards should be discussed
with your local fire protection specialist.

This device will not sense smoke unless the ventilation system is operating
and the cover is installed.

For this detector to function properly, it MUST be installed according to the in­structions in this manual. Furthermore, the detector MUST be operated within
ALL electrical and environmental specifications listed in this manual and the
sensor head installation manual. Failure to comply with these requirements
may prevent the detector from activating when smoke is present in the air
duct.

DEVICE STANDBY ALARM

RA100ZA 0mA 12mA Max.
RTS151 0mA 12mA Max.
RTS151KEY-A

Only (A) models are ULC listed.

[2] GENERAL DESCRIPTION

Smoke introduced into this air duct system will be distributed throughout the
entire building. Smoke detectors designed for use in air duct systems are used
to sense the presence of smoke in the duct.

Model DNRA Air Duct Smoke Detector uses photoelectric technology for the
detection of smoke. This detection method, when combined with an efficient
housing design, samples air passing through the duct and allows detection of
a developing hazardous condition. When sufficient smoke is sensed, an alarm
signal is initiated at the fire control panel monitoring the detector, and appro­priate action can be taken to shut off fans, blowers, change over air handling
systems, etc. These actions can facilitate the management of toxic smoke and
fire gases throughout the areas served by the duct system.

The DNRA incorporates a sensor cover tamper feature that provides a trou­ble signal at the panel immediately if the cover is removed or improperly in­stalled. Proper installation of the sensor cover removes the trouble condition.

When programmed with the system control panel, two LEDs on each duct
smoke detector light to provide local visible indication.

The DNRA provides a remote alarm output for use with auxiliary devices,
such as the RA100ZA remote LED annunciator, as well as remote test capabil­ity with the RTS151 or RTS151KEY-A Remote Test Stations.

[2.1] DETECTOR FEATURE SET

– Uses plug-in head ULC-listed as compatible with the system control panel

– Sampling tubes install from front and rear

– Compatible with existing accessories

– Able to address detector per code switches on sensor head

[3] CONTENTS OF THE DUCT SMOKE DETECTOR KIT

1. Sensor/power board assembly, covers, and factory-installed sensor head

2. Three #10 sheet metal screws for mounting

3. Drilling template

4. One sampling tube end cap

5. One plastic exhaust tube

NOTE: A DST sampling tube must be ordered to complete the installation. It
must be the correct length for the width of the duct where it will be installed.
See Table 1 on page 2 to determine the inlet tube required for different
duct widths.

ACCESSORY CURRENT LOADS AT 24 VDC

3333 Unity Drive, Mississauga, Ontario L5L 3S6

800/736-7672, FAX: [phone]

www.systemsensor.ca

12mA 12mA Max.

1 I56-3104-004
4/18/2019

REMOVE SCREW AND PIVOT

REPLACE SCREW

FIGURE 1. EXPLODED VIEW OF DUCT SMOKE DETECTOR COMPONENTS

EXHAUST TUBE

SAMPLING

TUBE
SOLD

SEPARATELY

SENSOR MODULE

SENSOR HEAD

SENSOR
MODULE
COVER

WIRING
COMPARTMENT

WIRING
COMPARTMENT
COVER

H0569-20

NOTE: Sensor Module sold separately. Refer to the control panel technical documentation for compatible ULC-listed heads with Remote Test Capability.

[4] DETECTOR INSTALLATION
[4.1] VERIFY DUCT AIR FLOW DIRECTION AND VELOCITY

Model DNRA detectors are designed to be used in air handling systems hav­ing air velocities of 100 to 4000 feet per minute. Duct widths from 6 inches to
12 feet can be accommodated. Be sure to check engineering specifications to
ensure that the air velocity in the duct falls within these parameters. If neces­sary, use a velocity meter (anemometer) to check the air velocity in the duct.

[4.2] DETERMINE MOUNTING LOCATION AND CONFIGURATION

On ducts wider than 18 inches it is recommended that the detector be
mounted downstream of a bend, obstruction in the duct, or the supply or
return air inlet.

Exception: Installation of duct detectors can be on or within a commercial
packaged rooftop heating and air-conditioning system, fire/smoke dampers
and economizers. They may be mounted in either the supply and/or return air
section as determined by local code.

Once a suitable location is selected, determine if the detector is to be mounted
in a side-by-side “rectangular” configuration or a top-over-bottom “square”
configuration as shown in Figure 2. If mounting in the square configuration,
remove the rear attachment screw, rotate the unit at hinge, and replace the
screw into the new attachment hole as shown in Figure 2. Do NOT remove
the hinge screw during this process. Final installation approval shall be
based upon passing differential pressure and smoke entry tests described in
Section 6 Measurement Tests.

FIGURE 2.

DETECTOR AS SHOWN BELOW.

TO SECURE DETECTOR

IN PLACE.

[4.3.1] FOR RECTANGULAR SIDE-BY-SIDE MOUNTING CONFIGURATION

Center punch at four target centers: two “A” for sampling tubes and two “B”
for the rectangular configuration mounting tabs as shown on mounting tem­plate. Drill pilot holes at target “A” centers and cut two 1.375 inch diameter
holes using a 13⁄8-inch hole saw or punch. Drill .156 inch diameter holes using
a 5⁄32 inch drill at target “B” centers.

[4.3.2] FOR SQUARE TOP-OVER-BOTTOM MOUNTING CONFIGURATION

Center punch at four target centers: two “A” for sampling tubes and two “C”
for the square configuration mounting tabs as shown on mounting template.
Drill pilot holes at target “A” centers and cut two 1.375 inch diameter holes us­ing a 13⁄8-inch hole saw or punch. Drill .156 inch diameter holes using a 5⁄32
inch drill at target “C” centers. If desired, drill an additional .156 inch hole at
the location of one of the mounting tabs on the lower housing.

[4.4] SECURE THE DUCT DETECTOR TO THE DUCT

Use two (rectangular configuration) or three (square configuration) of the pro­vided sheet metal screws to screw the duct detector to the duct.

CAUTION: Do not overtighten the screws.

[5] SAMPLING TUBE INSTALLATION
[5.1] SAMPLING TUBE SELECTION

The sampling tube must be purchased separately. Order the correct length, as
specified in Table 1, for width of the duct where it will be installed. The sam­pling tube length must extend at least 5/8 across the duct width for optimal
performance.

The sampling tube is always installed with the air inlet holes facing into the
air flow. To assist proper installation, the tube’s connector is marked with an
arrow. Make sure the sampling tube is mounted so that the arrow points into
the airflow as shown in Figure 3. Mounting the detector housing in a vertical
orientation is acceptable provided that the air flows directly into the sam­pling tube holes as indicated in Figure 3. The sampling tube and exhaust tube
can be mounted in either housing connection as long as the exhaust tube is
mounted downstream from the sampling tube.

TABLE 1. SAMPLING TUBES RECOMMENDED FOR DIFFERENT DUCT
WIDTHS

[4.3] DRILL THE MOUNTING HOLES

Remove the paper backing from the mounting template supplied. Affix the
template to the duct at the desired mounting location. Make sure the template
lies flat and smooth on the duct.

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H0550-00

Outside Duct Width Sampling Tube Recommended*

Up to 1 ft. DST1

1 to 2 ft. DST1.5

2 to 4 ft. DST3

4 to 8 ft. DST5

8 to 12 ft. DST10 (2-piece)

*Must extend a minimum of 5⁄8 the duct width