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32
Return Air Without Economizer
The sampling tube is located across the return air opening
on the unit basepan. See Fig. 40. The holes in the
sampling tube face downward, into the return air stream.
The sampling tube is attached to the control module
bushing that extends from the control box through the
partition into the return air section of the unit. The
sensing tube is shipped mounted to the Indoor Blower
Housing and must be relocated to the return air section of
the unit. Installation requires that this sensing tube be
attached to the control module bushing. See installation
steps.
Return Air Detector Sampling Tube
Controller module
Return Air Detector module
(shipping position shown)*
*RA detector must be moved from shipping position to operating position by installer
C07307
Fig. 40 -- Typical Return Air Detector Location
Return Air 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. 41. The holes in the
sampling tube face downward, into the return air stream.
The sampling tube is connected through tubing to the
return air sensor that is mounted on a bracket high on the
partition between return filter and controller location. The
Return Air Sensor is shipped in a flat--mounting location.
Installation requires that this sensor be relocated to its
operating location and the tubing to the sampling tube be
connected. See installation steps.
FIOP Smoke Detector Wiring and Response
All units:
The FIOP smoke detector is configured to
automatically shut down all unit operations when a smoke
condition is detected. See Fig. 42, Smoke Detector
Wiring.
Highlight A:
JMP 3 is factory--cut, transferring unit
control to smoke detector.
Highlight B:
Smoke detector NC contact set will open on
smoke alarm condition, de--energizing the ORN
conductor.
Highlight C:
24V power signal using the ORN lead is
removed at Smoke Detector input on Central Terminal
board (CTB); all unit operations cease immediately.
PremierLink
t
and
RTU--Open
Controls
:
Unit
operating functions (fan, cooling and heating) are
terminated as described above. In addition:
Highlight D:
On smoke alarm condition, the smoke
detector NO Alarm contact will close, supplying 24V
power to GRA conductor.
Highlight E:
GRA lead at Smoke Alarm input on LCTB
provides 24V signal to FIOP DDC control.
PremierLink:
This signal is conveyed to PremierLink
FIOP’s TB1 at terminal TB1--6 (BLU lead). This signal
initiates the FSD sequence by the PremierLink control.
FSD status is reported to connected CCN network.
RTU--OPEN:
The 24V signal is conveyed to the
RTU--OPEN J1--10 input terminal. This signal initiates the
FSD sequence by the RTU--OPEN control. FSD status is
reported to connected BAS network.
Using Remote Logic:
Five field use conductors are
provided for additional annunciation functions.
Additional Application Data:
Refer to Catalog No.
HKRNKA--1XA for discussions on additional control
features of these smoke detectors including multiple unit
coordination. See Fig. 42.
48H
C
Summary of Contents for 48HC D17 Series
Page 77: ...77 APPENDIX IV WIRING DIAGRAMS C12616 Fig 77 48HC D17 D28 Power Diagram 208 230 3 60 48HC...
Page 78: ...78 APPENDIX IV WIRING DIAGRAMS C12617 Fig 78 48HC D17 D28 Power Diagram 460 3 60 48HC...
Page 79: ...79 APPENDIX IV WIRING DIAGRAMS C12618 Fig 79 48HC D17 D28 Power Diagram 575 3 60 48HC...
Page 86: ...86 APPENDIX IV WIRING DIAGRAMS C13767 Fig 86 RTU OPEN Wiring Diagram 48HC...
Page 87: ...87 APPENDIX IV WIRING DIAGRAMS C13768 Fig 87 RTU OPEN Wiring Diagram with Humidi MiZer 48HC...