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TABLE 5
System Operation Monitor LED Troubleshooting Codes
Status LED
Status LED Description
Status LED Troubleshooting Information
Green Power"
Module has power.
24VAC control power is present at the module terminal.
Red Trip"
Thermostat demand signal
Y1 is present, but the com-
pressor is not running.
Heat pump only−Trip light will
be on during defrost board 5
minute delay with Y thermo-
stat call.
1
Compressor protector is open.
2
Outdoor unit power disconnect is open.
3
Compressor circuit breaker or fuse(s) is open.
4
Broken wire or connector is not making contact.
5
Low pressure switch open if present in the system.
6
Compressor contactor has failed to close.
Yellow Alert"
Flash Code 1
(Does not apply to heat
pump or to two−stage
split systems)
Long Run Time
Compressor is running ex-
tremely long run cycles
1
Low refrigerant charge.
2
Evaporator blower is not running.
3
Evaporator coil is frozen.
4
Faulty metering device.
5
Condenser coil is dirty
6
Liquid line restriction (filter drier blocked if present)
7
Thermostat is malfunctioning.
Yellow Alert"
Flash Code 2
System Pressure Trip
Discharge or suction pres-
sure out of limits or compres-
sor overloaded
1
High head pressure.
2
Condenser coil poor air circulation (dirty, blocked, damaged).
3
Condenser fan is not running.
4
Return air duct has substantial leakage.
5
If low pressure switch is present, check Flash Code 1 information.
Yellow Alert"
Flash Code 3
Short Cycling
Compressor is
running
only briefly
1
Thermostat demand signal is intermittent.
2
Time delay relay or control board is defective.
3
If high pressure switch is present, check Flash Code 2 information.
4
If low pressure switch is present, check Flash Code 1 information.
Yellow Alert"
Flash Code 4
Locked Rotor
1
Run capacitor has failed.
2
Low line voltage (contact utility if voltage at disconnect is low).
3
Excessive liquid refrigerant in the compressor.
4
Compressor bearings are seized.
Yellow Alert"
Flash Code 5
Open Circuit
1
Outdoor unit power disconnect is open.
2
Unit circuit breaker or fuse(s) is open.
3
Unit contactor has failed to close.
4
High pressure switch is open and requires manual reset.
5
Open circuit in compressor supply wiring or connections.
6
Unusually long compressor protector reset time due to extreme ambient temperature.
7
Compressor windings are damaged.
Yellow Alert"
Flash Code 6
Open Start Circuit
Current only in run circuit
1
Run capacitor has failed.
2
Open circuit in compressor start wiring or connections.
3
Compressor start winding is damaged.
Yellow Alert"
Flash Code 7
Open Run Circuit
Current only in start circuit
1
Open circuit in compressor start wiring or connections.
2
Compressor start winding is damaged.
Yellow Alert"
Flash Code 8
Welded Contactor
Compressor always runs
1
Compressor contactor failed to open.
2
Thermostat demand signal not connected to module.
Yellow Alert"
Flash Code 9
Low Voltage
Control circuit < 17VAC
1
Control circuit transformer is overloaded
2
Low line voltage (contact utility if voltage at disconnect is low.)
Flash code number corresponds to a number of LED flashes, followed by a pause, and then repeated.
TRIP and ALERT LEDs flashing at the same time indicates that the control circuit voltage is too low for operation.
Reset ALERT flash code by removing 24VAC power from monitor. Last ALERT flash code will display for 1 minute after monitor is powered on.
