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INSTALLATION INSTRUCTIONS
R-410A Split System Air Conditioner
421 01 5101 00
13
Figure 12
Comfort Alert
t
Diagnostics (some models)
Status LED
Status LED Description
Status LED Troubleshooting Information
Green “POWER”
Module has power
Supply voltage is present at module terminals
Red “TRIP”
Thermostat demand signal
Y1 is present, but the com‐
pressor is not running
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 system
6. Compressor contactor has failed open
Yellow “ALERT”
Flash Code
1
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 in system)
7. Thermostat is malfunctioning
Yellow “ALERT”
Flash Code
2
System Pressure Trip
Discharge or suction pres‐
sure out of limits or com‐
pressor 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 present in system, 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 defective
3. If high pressure switch present go to Flash Code 2 informa‐
tion
4. If low pressure switch present go to Flash Code 1 informa‐
tion
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 compressor
4. Compressor bearings are seized
Yellow “ALERT”
Flash Code
5
Open Circuit
1. Outdoor unit power disconnect is open
2. Compressor circuit breaker or fuse(s) is open
3. Compressor contactor has failed open
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 ex‐
treme 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 run wiring or connections
2. Compressor run winding is damaged
Yellow “ALERT”
Flash Code
8
Welded Contactor
Compressor always runs
1. Compressor contactor has failed closed
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)
S
Flash Code number corresponds to a number of LED flashes, followed by a pause and then repeated.
S
TRIP and ALERT LEDs flashing at same time means control circuit voltage is too low for operation.
S
Reset ALERT Flash code by removing 24VAC power from module.
S
Last ALERT Flash code is displayed for 1 minute after module is powered on.