AERCO KC1000 Boiler equipped with Mod-Box Controller - Manual (Page 47)

TROUBLESHOOTING
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9. Check the pins of the 15 pin connector for
proper insertion or wear.
10. If the connectors, pins, and continuity are
okay, reconnect wires #19 and #33 to the
lower switch and wires #18 and #33 to the
upper temperature switch.
11. Reconnect the 15 pin connector to the
control panel.
12. Reapply AC power to the unit.
13. If the over temperature fault still does not
clear consult your local AERCO
representative or contact a qualified service
technician
8.4.3 OTHER CAUSES
Other over temperature related causes include:
1. Improper settings of PID control settings.
2. Improper flow rates through the unit.
3. PID settings require tuning to the loop
If one of the above is suspect contact your local
AERCO representative for further assistance
8.5 FLAME FAULT
A LOCKOUT RUN FLAME message indicates
that the flame signal was lost after the unit
proved flame and was released to modulate. A
FLAME FAULT DURING IGN TRIAL message
indicates that flame was not recognized during
the ignition trial period.
8.5.1 Flame Fault While Firing
8.5.2 Flame Fault During Ignition Cycle
8.5.3 Safety Shut-Off Valve
8.5.4 Spark Ignitor
8.5.5 Flame Detector
8.5.6 Ignition Circuit
8.5.7 Air Fuel Valve Ignition Position Switch
8.5.8 Flame Detector Voltage
8.5.9 Residual Flame
Recommended Troubleshooting Equipment
• Digital or Analog Voltmeter
• Combustion Analyzer
• 8” and 16.5” Manometers
8.5.1 FLAME FAULT WHILE FIRING
1. Install a DC voltmeter in the flame test jacks
located on the front of the combustion
safeguard and start the unit.
2. Once flame is established, a steady reading
of approximately 5VDC should be observed.
3. Fire the unit at various firing rates (i.e
, 16%,
30%, 50%, 100% etc , ).
4. If flame signal is erratic at any time during
the test, combustion calibrate the unit as per
Section 4.of this manual.
5. If combustion calibration is okay remove the
burner and inspect it for debris that may
have fallen on it.
8.5.2 FLAME FAULT DURING IGNITION
TRIAL
1. Check that all gas supply valves are open
2. If the gas supply valves were open, start the
unit.
3. Remove the cover to the air/fuel valve.
Ensure that the air/fuel valve rotates to the
ignition position and engages the ignition
position switch. If the air/fuel valve does not
rotate to the ignition position proceed to
Section 8.7.7.
4. If the air/fuel valve rotates and engages the
ignition position switch during the trial for
ignition then visually watch/inspect the safety
shut-off valve, through the window on the
actuator half to determine if it is opening.
NOTE:
At the ignition cycle, the low fire switch is
made, and the safety shut-off valve is
energized. The OPEN disk in the safety
shut-off valve actuator window should
slowly move downward indicating that the
valve is operating correctly. If the valve
does not open proceed to Section 8.5.3
5. If the safety shut-off valve opens check the
spark ignitor as per Section 8.5.4 and the
flame detector, as per Section 8.5.5.
6. If the spark ignitor and flame detector are
okay, or require replacement and the flame
fault still persists, check the ignition circuit as
per Section 8.5.6.