Honeywell 7800 SERIES Manual page 12

Fault Code
Fault 11 Running Interlock powered at
*Running ILK On* improper sequence point.
Fault 12 Lockout Interlock powered at
*Lockout ILK On* improper sequence point.
Fault 13 Combustion airflow interlock
*Airflow Sw. On* fault during STANDBY.
Fault 14 High Fire Interlock Switch
*High Fire Sw.* failure to close during
PREPURGE.
Fault 15 Flame sensed when no flame is
*Flame Detected* expected during STANDBY.
Fault 16 No-flame detected during Pilot
*Flame-Out Timer* Flame Establishing Period.
Fault 17 Main flame failure during RUN
*Main Flame Fail* after flame is established an on
for at least 10 seconds.
Fault 18 Flame sensed when the shutter
*Flame Detected* is open and no flame is
expected during PREPURGE.
Table 7. Hold and Fault Message Summary. (Continued)
System Failure
17
7800 SERIES S7800A1142 KEYBOARD DISPLAY MODULE
Recommended Troubleshooting
1. Check wiring to make sure that interlocks are connected
properly between terminals 6 and 7. Correct any errors.
2. Reset and sequence the relay module.
3. If the fault persists, measure the voltage between terminals 6
and L2(N) (ground), then terminals 7 and L2(N). If there is line
supply voltage present at terminal 6 when the controller is off,
the controller switch may be bad or jumpered.
4. If steps 1 through 3 are correct and there is line supply voltage
present at terminal 7 when the controller is closed and the fault
persists, check for a welded or jumpered Running Interlock,
Lockout Interlock, or Airflow Switch. Correct any errors.
5. If steps 1 through 4 are correct and the fault persists, replace
the relay module.
1. Check wiring and correct any errors.
2. Reset and sequence the relay module.
3. Use either the manual motor potentiometer to drive the motor
to the High Fire position or use the Run/Test Switch option, if
available. Sequence to Prepurge drive to High Fire and place
in the Test position. Adjust the High Fire Switch while in this
state to make sure that it closes properly.
4. Measure the voltage between terminal 19 and L2(N) while in
the Prepurge drive to High Fire state. Line supply voltage
should be present. If not, the switch adjustment is incorrect
and/or the switch is defective and needs replacing.
5. Reset and sequence the relay module. If the line supply
voltage was present between the High Fire Switch and terminal
19, and the fault still persists, replace the relay module.
1. Check that the flame is not present in the combustion
chamber; correct any errors.
2. Make sure that the flame amplifier and flame detector are
compatible.
3. Check wiring and correct any errors.
4. Remove the flame amplifier and inspect the connections.
Reset the flame amplifier.
5. Reset and sequence the relay module.
6. If the code reappears, replace the amplifier and/or the flame
detector.
7. If the fault persists, replace the relay module.
1. Measure the flame signal. If one exists, make sure it meets
specifications. Make any necessary burner adjustments using
manufacturer instructions.
2. Make sure that the flame amplifier and flame detector are
compatible.
3. If the code reappears, replace the amplifier and/or the flame
detector.
4. If the fault persists, replace the relay module.
1. Inspect the main fuel valve(s) and connection(s).
2. Make sure that the fuel pressure is high enough to supply fuel
to the combustion chamber.
3. Check the flame detector sighting for adequate flame signal
throughout the burner firing rate.
1. Check that flame is not present in the combustion chamber.
Correct any errors.
2. Make sure that the flame amplifier and flame detector are
compatible.
3. Check the wiring and correct any errors. Make sure F and G
wires are in individual conduits and protected from stray noise
pickup.
4. Remove the flame amplifier and inspect the connectors. Reset
the flame amplifier.
5. Reset and sequence the relay module.
6. If the code reappears, replace the flame amplifier and/or the
flame detector.
7. If the fault persists, replace the relay module.
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