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Resetting Alarm and Trouble Condition Trips:
Manual reset is required to restore smoke detector systems
to Normal operation. For installations using two sensors,
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
Controller’s Trouble LED Does
1. Verify that the remote test/station is wired as shown
in Fig. 27. 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 linebreak motor protection.
Overtemperature
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.
48L
C
Summary of Contents for 48LC 05
Page 10: ...10 COOLING CHARGING CHARTS C14037 Fig 13 Cooling Charging Charts 3 Ton 48LC ...
Page 11: ...11 COOLING CHARGING CHARTS cont C14038 Fig 14 Cooling Charging Charts 4 Ton 48LC ...
Page 12: ...12 COOLING CHARGING CHARTS cont C14039 Fig 15 Cooling Charging Charts 5 Ton 48LC ...
Page 35: ...35 WIRING DIAGRAMS C14043 Fig 44 Unit Wiring Diagram Power 208 230V 460V 3 Phase 48LC ...
Page 36: ...36 C14044 Fig 45 Unit Wiring Diagram Power 575V 3 Phase 48LC ...
Page 37: ...37 C14045 Fig 46 Unit Wiring Diagram Control 48LC ...
Page 47: ...47 48LC ...