AERCO KC1000 Heater w/Mod-Box Controller - Manual (Page 51)

TROUBLESHOOTING
46
21. If wires #12 and #29 have continuity, inspect
the pin on wire #12 in the 9-pin connector for
proper insertion or signs of wear
22. Inspect the connector on wire #29 at the AC
wiring box end for a loose connection.
23. Make any necessary repairs.
24. Once all wiring and connections have been
inspected or repaired, reconnect wires #12
and #29 to the ignition transformer.
Reconnect wire #29 to its proper position in
the AC wiring box.
25. Reconnect the 9-pin connector to the control
panel ensuring it is locked into place.
26. Reinstall the cover plates on the ignition
transformer and the AC wiring box.
27. Be sure to reinstall the spark ignitor and
ignitor contactor if necessary and reconnect
the ignition cable to the ignition transformer
and the ignition contactor.
28. Reopen the leak detection valve.
29. Restore electrical power to the unit and start
the unit.
30. If the flame fault persists, replace the
Combustion Control
7.5.7 FLAME DETECTOR VOLTAGE
1. Disconnect electrical power to the unit.
2. Remove the flame detector lead wire from
the flame detector.
3. Connect an AC voltmeter between the flame
detector lead wire and the unit’s frame.
WARNING!
A SHOCK POTENTIAL OF 230 TO 400
VAC EXISTS ON THE FLAME DETECTOR
LEAD WIRE.
4. Restore electrical power to the unit.
5. An AC voltage reading of approximately 345
VAC should be observed.
6. If 345 VAC is observed, proceed to Section
7.6.2, Step 8.
7. If 345 VAC is not observed, disconnect
electrical power to the unit.
8. Disconnect the 9-pin connector from the
control panel.
9. Referring to system schematic 161412 in
Appendix F, locate wire #9.
10. Check wire #9 for continuity
11. Check the flame detector end of wire #9 for
loose connections. Inspect the pins in the 9-
pin connector for proper insertion and signs
of wear.
12. Repair if necessary.
13. If wire #9 has continuity and all connections
are okay or a repair was performed,
reconnect the flame detector lead to the
flame detector. Reconnect the 9-pin
connector to the control panel.
14. Restore electrical power to the unit and
restart the unit.
15. If the flame fault persists, replace the
combustion control.
7.5.8 RESIDUAL FLAME
Once the KC1000 has stopped firing, it
continues to monitor the flame circuit. If a
residual flame exists, the unit will indicate a
LOCKOUT fault. The source of a residual flame
is a leaking safety shutoff valve. To check for a
leaking safety shutoff valve proceed as follows:
1. Shut the unit off by switching the ON-OFF
switch to the Off position
2. Locate the leak detection valve, between the
safety shutoff valve and the differential
pressure regulator.
3. Shut the valve and remove a set-screw from
its 1/8” leak detection port.
4. Install an 8” or 16” manometer.
5. Monitor the manometer for signs of an
increase in gas pressure.
6. If there is an increase in gas pressure,
replace the gas train.