Daikin ComfortNet DX18TC Service Instructions Manual page 52

SERVICING
Integrated control
module diagnostic/status
LED display shows the
indicated code.
displays '---' in the
temperature display area.
Heat pump fails to operate
in heating mode.
Integrated control
module diagnostic/status
LED display shows the
indicated code.
displays error message.
Air conditioner/heat pump
fails to operate.
Integrated control
module diagnostic/status
LED display shows the
indicated code.
Air conditioner/heat pump
fails to operate.
Integrated control
module diagnostic/status
LED display shows the
indicated code.
Air conditioner/heat pump
fails to operate.
Integrated control
module diagnostic/status
LED display shows the
indicated code.
displays error message.
Air conditioner/heat
pump operates at reduced
performance.
Air conditioner/heat pump
operating at low stage
when expected to operate
at high stage.
Integrated control
module diagnostic/status
LED display shows the
indicated code.
52
A 2 Outdoor air AIR
temp sensor
fault FLT
A 3 Outdoor coil COIL
temp sensor
fault FLT
E 5 Open fuse
FUSE
E E Board mis-
operation FAULT
b 0 Circulator MOTOR
blower motor
is not running
when it
should be
running.
b 9 Airflow is LOW ID
lower than AIRFLOW
demanded
A2 Shorted sensor. Check sensor
Open sensor. connection.
Sensor Replace open/
disconnected. shorted sensor.
Sensor out of
range.
A3 Shorted sensor Check sensor
Open sensor. connection.
Sensor. Replace open/
disconnected. shorted sensor.
Sensor out of
range.
E5 Short in low Locate and
voltage wiring. correct short
in low voltage
wiring.
EE Compressor Replace control.
relay contacts
welded.
b0 Indoor blower Check indoor
motor problem. blower motor.
Communications Check indoor
error between blower motor
indoor and wiring.
outdoor unit. Check indoor unit
control.
Repair/ replace
any faulty wiring.
Repair/ replace
indoor blower
motor or control.
b9 Indoor blower Check indoor
motor problem blower motor.
Blocked filters. Check filters;
Restrictive/ clean/replace as
undersized needed.
ductwork Check ductwork;
Indoor/ outdoor resize as needed.
unit miss-match. Verify indoor and
outdoor units are
properly matched.
PCBHR104
Turn power OFF prior
to repair.
Replace with correct
replacement part.
Turn power OFF prior
to repair.
Replace with correct
replacement part.
Turn power OFF prior
to repair.
Replace fuse with
3-amp automotive type.
Turn power OFF prior
to repair
Replace with correct
replacement part.
Turn power OFF prior
to repair.
Applies only to fully
communicating system
thermostat.
Replace with correct
replacement part.
Turn power OFF prior
to repair.
Applies only to fully
communicating system
thermostat.
Replace with correct
replacement part. See
specification sheet(s)
for airflow requirements
and maximum external
static pressure.
See specification
sheets for approved
system matches.