11
LED Troubleshooting Information Continued
Status LED Status LED Description Status LED Troubleshooting 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
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)
• Check wiring connections
3. Excessive liquid refrigerant in compressor
4. Compressor bearings are seized
• Measure compressor oil level
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
• Check compressor contactor wiring and connectors
• Check for compressor contactor failure
(burned, pitted or open)
• Check wiring and connectors between
supply and compressor
• Check for low pilot voltage at compressor contactor coil
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
• Check compressor motor winding resistance
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
•Check wiring and connectors between
supply and the compressor “S” terminal
3.Compressor start winding is damaged
• Check compressor motor winding resistance
Yellow “ALERT”
Flash Code 7
Open Run Circuit
Current only in start circuit
1.Open circuit in compressor run wiring or connections
• Check wiring and connectors between supply and the
compressor “R” terminal
2.Compressor run winding is damaged
• Check compressor motor winding resistance
Yellow “ALERT”
Flash Code 8
Welded Contactor
Compressor always runs
1.Compressor contactor has failed closed
2.Thermostat demand signal not connected to module
Note: Disabled on 543-0010-01, 943-0010-01
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)
• Check wiring connections
Flash Code number corresponds to a number of LED flashes, followed by a pause and then repeated. TRIP
and ALERT LEDs flashing at same time means control circuit voltage is too low for operation.
To Next Page
Loading...
