![background image](http://html.mh-extra.com/html/system-sensor/dh400acdciht/dh400acdciht_installation-and-maintenance-instructions-manual_1422755001.webp)
D400-64-00 1 I56-991-08R
DH400ACDCIHT Air Duct Smoke Detector
INSTALLATION AND MAINTENANCE INSTRUCTIONS
3825 Ohio Avenue, St. Charles, Illinois 60174
1-800-SENSOR2, FAX: 630-377-6495
www.systemsensor.com
Before Installing
Please thoroughly read the System Sensor
Guide for Proper
Use of Smoke Detectors in Duct Applications
(A05-1004),
which provides detailed information on detector spacing,
placement, zoning, wiring, and special applications. Copies
of this manual are available online at www.systemsensor.com
or via System Sensor’s toll free fax-back service, Documents
on Demand at 800/736-7672. NFPA Standards 72 and 90A
should also be referenced for detailed information.
NOTICE:
This manual should be left with the owner/user
of this equipment.
IMPORTANT:
This detector must be tested and maintained
regularly following NFPA 72 requirements. The detector
should be cleaned at least once a year.
WARNING
This detector is intended for use only with the 1451DHHT
detector head (supplied).
Table of Contents Page
[1] General Description 1
[2] Exploded View of Duct Detector Components 2
[3] Contents of the Duct Detector Kit 2
[4] Installation Sequence 2
[5] Duct Detector Maintenance and Test Procedures 8
[6] Detector Cleaning Procedures 9
[7] Specifications 10
[8] DH400 OE-1 Description and Installation 11
Warranty 12
List of Tables and Figures Page
Fig. 1: Duct Detector Exploded View 2
Fig. 2: Installation of Sampling Tube Gaskets 3
Fig. 3: Mounting Location of Speed Nuts 3
Table 1: Inlet Sampling Tube Selection 3
Fig. 4: Inlet Sampling Tube 4
Fig. 5: Sampling Tube Mounting Configurations 4
Fig. 6: Sampling Tube Filter Installation 5
Fig. 7: Wiring Diagram 6
Fig. 8: Wiring Diagram – No Control Panel 7
Fig. 9: Wiring Diagram – Accessories 8
Fig. 10: Testing Detector Alarm 9
Fig. 11: Detector Head Removal 9
Fig. 12: RTS451/RTS451KEY Test Coil Installation 10
Fig. 13: Ion Head Exploded View 10
[1] General Description
An HVAC system supplies conditioned air to virtually every
area of a building. Smoke introduced into this air duct sys-
tem will be distributed to the entire building. Smoke detec-
tors designed for use in air duct systems are used to sense
the presence of smoke in the duct.
Model DH400ACDCIHT Air Duct Smoke Detectors are sup-
plied with the model 1451DHHT ionization detector head.
This smoke detection method is combined with an efficient
housing design that samples air passing through a duct
and allows detection of a developing hazardous condition.
When sufficient smoke is sensed, an alarm signal is initi-
ated at the fire control panel monitoring the detector, and
appropriate action can be taken to shut off fans and blow-
ers, 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 DH400ACDCIHT air duct smoke detector is designed to
operate from 24 VDC, 24 VAC, 120 VAC, or 240 VAC. Alarm
and supervisory relay contacts are available for control
panel interface (alarm initiation), HVAC control, and other
auxiliary functions. This detector is not designed for 2-wire
applications.
For testing, the alarm can be enabled by a magnet activated
test switch or by the optional remote test station. The duct
smoke detectors latch into alarm state when alarm occurs.
LEDs on each detector illuminate to provide local alarm
indication, and optional accessories offer a variety of
annunciation capabilities.
The detector can be reset by a momentary power inter-
ruption, by the magnet activated reset switch, or by the
optional remote test station.
NOTICE:
The DH400ACDCIHT can be installed outdoors
using the optional accessory DH400 OE-1.
Please refer to section 9 for a description and
installation instructions.