18
Status LED
Status LED
Description
Status LED Troubleshooting Information
Yellow “ALERT”
Flash Code 3
Short Cycling
/ Compressor
is running only
briefl y
• Thermostat demand signal is intermittent
• Low line voltage (contact utility if voltage at disconnect is low)
• Excessive liquid refrigerant in compressor
• Compressor bearings are seized
Yellow “ALERT”
Flash Code 4
Locked Rotor
• Run capacitor has failed
• Low line voltage (contact utitlity if voltage at disconnect is
low)
• Check wiring connections
• Excessive liquid refrigerant in compressor
• Compressor bearings are seized
• Measure compressor oil level
Yellow “ALERT”
Flash Code 5
Open Circuit
• Outdoor unit power disconnect is open
• Compressor circuit breaker or fuse(s) is open
• 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
— High pressure switch is open and requires manual reset
• Open circuit in compressor supply wiring or connections
• Unusually long compressor protector reset time due to extreme
ambient temperature
• Compressor windings are damaged
— Check compressor motor winding resistance
Yellow “ALERT”
Flash Code 6
Open Start Circuit
Current only in
run circuit
• Run capacitor has failed
• Open circuit in compressor start wiring or connections
— Check wiring and connectors between supply and the
compressor S terminal
• Compressor start winding is damaged
— Check compressor motor winding resistance
Yellow “ALERT”
Flash Code 7
Open run circuit
Current only in
start circuit
• Open circuit in compressor run wiring or connections
— Check wiring and connectors between supply and the
compressor R terminal
• Compressor run winding is damaged
— Check compressor motor winding resistance
Yellow “ALERT”
Flash Code 8
Welded Contactor
Compressor
always runs
• Compressor contactor has failed closed
• Thermostat demand signal not connected to module
Yellow “ALERT”
Flash Code 9
Low Voltage
Control circuit
< 17VAC
• Control circuit transformer is overloaded
• Low line voltage (contact utility if voltage at disconnect is low)
• Check wiring connections
* Flash code number corresponds to a number of LED fl ashes, followed by a pause and then
repeated. Trip and alert LED’s fl ashing at same time means control circuit voltage is too low for
operation.
Table 4. LED Diagnostics - Continued
TROUBLESHOOTING - CONTINUED