D400-13-00 1 I56-555-08
DH400ACDC Air Duct Smoke Detector
INSTALLATION AND MAINTENANCE INSTRUCTIONS
A Division of Pittway
3825 Ohio Avenue, St. Charles, Illinois 60174
1-800-SENSOR2, FAX: 630-377-6495
Before Installing
Please thoroughly read the System Sensor Guide for Proper
Use of Smoke Detectors in Duct Applications (I56-473),
which provides detailed information on detector spacing,
placement, zoning, wiring, and special applications. Copies
of this manual are available from System Sensor. NFPA
Standards 72 and 90A should also be referenced for de-
tailed 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.
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] Limitations of Duct Detectors 2
[5] Installation Sequence 2
[6] Duct Detector Maintenance and Test Procedures 8
[7] Detector Cleaning Procedures 10
[8] Specifications 12
Warranty 13
Detector Test log 16
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: Wiring Diagram 6
Fig. 7: Wiring Diagram – No Control Panel 7
Fig. 8: Wiring Diagram – Accessories 8
Fig. 9: Sampling Tube Filter Installation 8
Fig. 10: Testing Detector Alarm 9
Fig. 11: Detector Head Removal 9
Fig. 12: RTS451/RTS451KEY Test Coil Installation 10
Fig. 13: Photo Head Exploded View 11
Fig. 14: Ion Head Exploded View 11
[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 DH400ACDC Air Duct Smoke Detectors are supplied
with model 1451DH ionization detector heads or model
2451 photoelectronic detector heads. These two smoke de-
tection methods are combined with an efficient housing de-
sign that samples air passing through a duct and allows
detection of a developing hazardous condition. When suffi-
cient smoke is sensed, an alarm signal is initiated at the fire
control panel monitoring the detector, and appropriate ac-
tion can be taken to shut off fans and 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.
DH400ACDC detectors are 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 func-
tions. These detectors are not designed for 2-wire applica-
tion.
For testing, the alarm can be enabled by a magnet activated
test switch, by insertion of a calibrated test card into the
sensing chamber (photoelectronic version only), or by the
optional remote test station. The duct smoke detectors
latch into alarm state when alarm occurs. LEDs on each de-
tector illuminate to provide local alarm indication, and op-
tional accessories offer a variety of annunciation
capabilities.
The detector can be reset by a momentary power interrup-
tion, by the magnet activated reset switch, or by the op-
tional remote test station.
To Next Page
Need help?
General
