Condensing Unit, Heat Pump, Blower and Coil Service Instructions
SERVICING
48
Symptoms of Abnormal Operation
(Legacy & ComfortNet™ Thermostat)
Dia gnostic/ Status LED Codes
Fault
Description
Comf or t N e t ™
Thermostat Only
Possible Causes
Corrective Actions Notes & Cautions
Green Ye l l o w Red Red Y1 Message Code
• Very long run time.
• Four consecutive compressor protector
trips with average run time between
trips greater than 3 hours.
• Compressor operating at high speed
and outdoor fan operating at low speed
• Integrated control module
diagnost ic/status LED’s display the
indicated code.
OFF 1 Flash OFF ON if call
present;
OFF if no
call
• Low Side Fault. LOW SIDE
FAULT
01 • Low refrigerant charge.
• Restriction in liquid line.
• Indoor blower motor
failure.
• Indoor thermostat set
extremely low.
• Verify re fri gerant
charge; adjust as
needed.
• Check for restricted
liquid line;
repair/replace as
needed.
• Check indoor blower
motor; repair/replace
as needed.
• Check indoor
thermostat setting.
• Turn power OFF prior
to repair.
• Fault will clear after 30
consecutive normal
cycles.
• Fault may be cleared by
cycling 24VAC to
control.
• Replace with correct
replacement part(s).
• Compressor a nd out door fan are off.
• Thermostat demand is present.
• Integrated control module
diagnost ic/status LED’s display the
indicated code.
ON 1 Flash OFF ON if call
present;
OFF if no
call
• Low Pressure
CO Trip.
LPS OPEN 01
• Low refrigerant charge.
• Restriction in liquid line.
• Indoor blower motor
failure.
• Indoor thermostat set
extremely low.
• Verify re fri gerant
charge; adjust as
needed.
• Check for restricted
liquid line;
repair/replace as
needed.
• Check indoor blower
motor; repair/replace
as needed.
• Check low pressure
switch; repair/replace
as needed.
• Check indoor
thermostat setting.
• Turn power OFF prior
to repair.
• Replace with correct
replacement part(s).
• Compressor a nd out door fan are off.
• Low pressure switch trip 3 times within
same thermostat demand.
• Thermostat demand is present.
• Integrated control module
diagnost ic/status LED’s display the
indicated code.
• ComfortNet™ thermostat “Call for
Service” icon illuminated.
• ComfortNet™ thermostat scrolls
“Check Air Conditioner” or “Check
Heat Pump” message.
ON 1 Flash ON ON if call
present;
OFF if no
call
• LPCO Lockout
(3 Trips).
LPS
LOCKOUT
01
• Low refrigerant charge.
• Restriction in liquid line.
• Indoor blower motor
failure.
• Indoor thermostat set
extremely low.
• Verify re fri gerant
charge; adjust as
needed.
• Check for restricted
liquid line;
repair/replace as
needed.
• Check indoor blower
motor; repair/replace
as needed.
• Check low pressure
switch; repair/replace
as needed.
• Check indoor
thermostat setting.
• Turn power OFF prior
to repair.
• Must clear fault by
cycling 24VAC to
control.
• Replace with correct
replacement part(s).
PCBHR101-103
PBBGR101-102