Daikin FC Series - Fault Codes

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Table 7: Fault codes
Blinking Fault Codes...
Fault Code System Failure
Code 1-1
*Low AC Line Voltage*
Low AC Line detected.
a. Check the relay module and display module
connections.
b. Reset and sequence the Relay Module.
c. Check the 7800 power supply and make
sure that frequency and voltage meet
specications.
d. Check the backup power supply, as
appropriate.
Code 1-2
*AC QualityProblem*
Excessive noise or device running on
slow, fast, or AC line dropout detected.
Code 2-1
*UnexpectedFlame Signal*
Flame sensed when no ame is expected
during STANDBY or PURGE.
a. Check that ame is not present in the
combustion chamber; correct any errors.
b. Make sure that the ame amplier and
ame detector are compatible.
c. Check the wiring and correct any errors.
d. Remove the ame amplier and inspect its
connections. Reseat the amplier.
e. Reset and sequence the relay module.
f. If the code reappears, replace the ame
amplier and/or the ame detector.
g. If the fault persists, replace the relay
module.
Code 2-2
*Flame Signal Absent*
No-ame time present at the end of the
Pilot Flame Establishing Period; lost
during the Main Flame Establishing
Period or during RUN.
a. Measure the ame signal. If one exists,
verify that it meets specications.
b. Make sure that the ame amplier and
ame detector are compatible.
c. Inspect the main fuel valve(s) and valve
connection(s).
d. Verify that the fuel pressure is su󰀩cient
to supply fuel to the combustion chamber.
Inspect the connections to the fuel pressure
switches. Make sure they are functioning
properly.
e. Inspect the Airow Switch and make sure
that it is functioning properly.
f. Check the ame detector sighting position;
reset and recycle. Measure the ame signal
strength. Verify that it meets specications.
If not, refer to the ame detector and/or
ame amplier checkout procedures in the
installation instructions.
g. Replace the ame amplier and/or the
ame detector, if necessary.
h. If the fault persists, replace the relay module
IM 684-6 • ROOFTOP SYSTEMS 30 www.DaikinApplied.com
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