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Fig. 50 — Typical Return Air Smoke Detector
Location
RETURN AIR SMOKE DETECTOR SENSOR WITH
ECONOMIZER
The sampling tube is inserted through the side plates of the
economizer housing, placing it across the return air opening on
the unit basepan. See Fig. 51. The holes in the sampling tube
face downward, into the return air stream. The sampling tube is
connected using tubing to the return air sensor mounted on a
bracket high on the partition between return filter and control-
ler location. The sensor is shipped in a flat-mounting location.
Installation requires the sensor be relocated to its operating lo-
cation and the tubing to the sampling tube be connected. See
“Completing Installation of Return Air Smoke Sensor” for in-
stallation steps.
Fig. 51 — Return Air Sampling Tube Location (View
reoriented to show opposite side for clarity)
Completing Installation of Return Air Smoke
Detector
Use the following steps to complete the installation of the Re-
turn Air Smoke Detector.
1. Unscrew the two screws holding the Return Air Sensor
Detector plate. See Fig. 52. Save the screws.
Fig. 52 — Return Air Smoke Detector Module
Shipping Position
2. Remove the Return Air Smoke Sensor Module and its
detector plate.
3. Rotate the detector plate so the sensor is facing outwards
and the sampling tube connection is on the bottom. See
Fig. 53.
4. Screw the sensor and detector plate into operating position
using screws from Step 1. Ensure the sampling tube con-
nection is on the bottom and the exhaust tube is on the top.
5. Connect the flexible tube on the sampling inlet to the sam-
pling tube on the basepan.
6. For units with an economizer, the sampling tube is inte-
grated into the economizer housing but connecting the
flexible tubing to the sampling tube is the same.
Fig. 53 — Return Air Sensor Operating Position
*RA detector must be moved from shipping
position to operating position by installer.
RETURN AIR DETECTOR
SAMPLING TUBE
RETURN AIR
DETECTOR MODULE
(Shipping position
shown)*
CONTROLLER
MODULE
RETURN AIR
SAMPLING TUBE
SAMPLE TUBE
SCREWS
FLEXIBLE EXHAUST
TUBES
RETURN AIR SENSOR
(Operating Position Shown)
SCREWS (2)
SAMPLE TUBE
CONTROLLER
MODULE
Summary of Contents for 50HCQ04---12
Page 86: ...86 APPENDIX E WIRING DIAGRAMS cont Fig C 50HCQA04 A05 Control Wiring Diagram 575 3 60...
Page 88: ...88 APPENDIX E WIRING DIAGRAMS cont Fig E 50HCQ 06 Control Wiring Diagram 575 3 60...
Page 93: ...93 APPENDIX E WIRING DIAGRAMS cont Fig J 50HCQ 04 05 06 Power Wiring Diagram 208 230 1 60...
Page 94: ...94 APPENDIX E WIRING DIAGRAMS cont Fig K 50HCQ 04 05 06 Power Wiring Diagram 208 230 3 60...
Page 95: ...95 APPENDIX E WIRING DIAGRAMS cont Fig L 50HCQ 04 05 06 Power Wiring Diagram 460 3 60...
Page 96: ...96 APPENDIX E WIRING DIAGRAMS cont Fig M 50HCQ 04 05 06 Power Wiring Diagram 575 3 60...
Page 100: ...100 APPENDIX E WIRING DIAGRAMS cont Fig Q 50HCQ 12 Power Wiring Diagram 208 230 3 60...
Page 101: ...101 APPENDIX E WIRING DIAGRAMS cont Fig R 50HCQ 12 Power Wiring Diagram 460 3 60 575 3 60...
Page 102: ...102 APPENDIX E WIRING DIAGRAMS cont Fig S 50HCQ PremierLink Control Diagram...
Page 103: ...103 APPENDIX E WIRING DIAGRAMS cont Fig T 50HCQ RTU Open Control Diagram...