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33
the duct smoke detector does not differentiate which
sensor signals an alarm or trouble condition. Check each
sensor for Alarm or Trouble status (indicated by LED).
Clear the condition that has generated the trip at this
sensor. Then reset the sensor by pressing and holding the
reset button (on the side) for 2 seconds. Verify that the
sensor’s Alarm and Trouble LEDs are now off. At the
controller, clear its Alarm or Trouble state by pressing and
holding the manual reset button (on the front cover) for 2
seconds. Verify that the controller’s Alarm and Trouble
LEDs are now off. Replace all panels.
Troubleshooting
Controller’s Trouble LED is On
1. Check the Trouble LED on each sensor connected to
the controller. If a sensor’s Trouble LED is on, de-
termine the cause and make the necessary repairs.
2. Check the wiring between the sensor and the control-
ler. If wiring is loose or missing, repair or replace as
required.
Controller’s Trouble LED is Flashing
1. One or both of the sensors is 100% dirty.
2. Determine which Dirty LED is flashing then clean
that sensor assembly as described in the detector
cleaning section.
Sensor’s Trouble LED is On
1. Check the sensor’s Dirty LED. If it is flashing, the
sensor is dirty and must be cleaned.
2. Check the sensor’s cover. If it is loose or missing, se-
cure the cover to the sensor housing.
3. Replace sensor assembly.
Sensor’s Power LED is Off
1. Check the controller’s Power LED. If it is off, de-
termine why the controller does not have power and
make the necessary repairs.
2. Check the wiring between the sensor and the control-
ler. If wiring is loose or missing, repair or replace as
required.
Controller’s Power LED is Off
1. Make sure the circuit supplying power to the control-
ler is operational. If not, make sure JP2 and JP3 are
set correctly on the controller before applying power.
2. Verify that power is applied to the controller’s supply
input terminals. If power is not present, replace or re-
pair wiring as required.
Remote Test/Reset Station’s Trouble LED Does Not
flash When Performing a Dirty Test, But the Control-
ler’s Trouble LED Does
1. Verify that the remote test/station is wired as shown
in Fig. 42. Repair or replace loose or missing wiring.
2. Configure the sensor dirty test to activate the control-
ler’s supervision relay. See “Changing sensor dirty
test operation.”
Sensor’s Trouble LED is On, But the Controller’s
Trouble LED is OFF
Remove JP1 on the controller.
PROTECTIVE DEVICES
Compressor Protection
Overcurrent
The compressor has internal line--break motor protection.
Over--temperature
The compressor has an internal protector to protect it
against excessively high discharge gas temperatures.
High Pressure Switch
The system is provided with a high pressure switch
mounted on the discharge line. The switch is
stem--mounted and brazed into the discharge tube. Trip
setting is 630 psig
10 psig (4344
69 kPa) when hot.
Reset is automatic at 505 psig (3482 kPa).
Low Pressure Switch
The system is protected against a loss of charge and low
evaporator coil loading condition by a low pressure switch
located on the suction line near the compressor. The
switch is stem--mounted. Trip setting is 54 psig
5 psig
(372
34 kPa). Reset is automatic at 117
5 psig (807
34 kPa).
Evaporator Freeze Protection
The system is protected against evaporator coil frosting
and low temperature conditions by a temperature switch
mounted on the evaporator coil hairpin. Trip setting is
30
_
F
5
_
F (--1
_
C
3
_
C). Reset is automatic at 45
_
F
(7
_
C).
Supply (Indoor) Fan Motor Protection
Disconnect and lockout power when servicing fan motor.
The standard supply fan motor is equipped with internal
overcurrent and over--temperature protection. Protection
devices reset automatically.
The High Static option supply fan motor is equipped with
a pilot--circuit Thermix combination over--temperature/
overcurrent protection device. This device resets
automatically. Do not bypass this switch to correct
trouble. Determine the cause and correct it.
48H
C
Summary of Contents for 48HC*04-14
Page 94: ...94 APPENDIX IV WIRING DIAGRAMS C14007 Fig 80 48HC A04 A06 YAC Power Diagram 230 1 60 48HC ...
Page 96: ...96 APPENDIX IV WIRING DIAGRAMS C14013 Fig 82 48HC A04 A06 YAC Power Diagram 575 3 60 48HC ...
Page 97: ...97 APPENDIX IV WIRING DIAGRAMS C14018 48HC ...
Page 98: ...98 APPENDIX IV WIRING DIAGRAMS C14019 48HC ...
Page 99: ...99 APPENDIX IV WIRING DIAGRAMS C13484 Fig 83 48HC D08 D09 YAC Power Diagram 230 460 3 60 48HC ...
Page 100: ...100 APPENDIX IV WIRING DIAGRAMS C14024 Fig 84 48HC D08 D09 YAC Power Diagram 575 3 60 48HC ...
Page 101: ...101 APPENDIX IV WIRING DIAGRAMS C14027 Fig 85 48HC D12 YAC Power Diagram 230 460 3 60 48HC ...
Page 102: ...102 APPENDIX IV WIRING DIAGRAMS C14029 Fig 86 48HC D12 YAC Power Diagram 575 3 60 48HC ...
Page 104: ...104 APPENDIX IV WIRING DIAGRAMS C14032 Fig 88 48HC D14 YAC Power Diagram 230 460 3 60 48HC ...
Page 105: ...105 APPENDIX IV WIRING DIAGRAMS C12462 Fig 89 48HC D14 YAC Power Diagram 575 3 60 48HC ...
Page 123: ...123 APPENDIX IV WIRING DIAGRAMS C12690 Fig 107 PremierLink System Control Wiring Diagram 48HC ...
Page 125: ...125 APPENDIX IV WIRING DIAGRAMS C14034 Fig 109 RTU Open Wiring Diagram 48HC ...