AERCO KC1000 Boiler equipped with Mod-Box Controller - Manual (Page 48)

TROUBLESHOOTING
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7. If the flame fault still persists after checking
the above, measure the flame detector lead
voltage as per Section 8.5.7.
8. If the flame fault still persists after checking
all of the above, remove the burner and
inspect for debris.
If the flame fault still persists after the above,
replace the combustion safeguard.
8.5.3 SAFETY SHUT-OFF VALVE
1. Start the unit.
2. When the starting sequence reaches the
ignition trial cycle, observe the response of
the safety shut-off valve through the window
in the actuator portion
3. At the ignition cycle, the OPEN disc should
slowly begin to descend down as the
hydraulic actuator opens the valve.
4. If the actuator does not open the valve,
disconnect AC power to the unit.
5. Remove the actuator portion from the valve
body and inspect for signs of leaking
hydraulic fluid.
6. If the actuator is not leaking, set it back on
the valve body and remove the electrical
cover plate exposing the control wiring.
7. Temporarily secure the actuator to the valve
body with the control wiring facing outward
for easy access.
8. Referring to system schematic 161413 in
Appendix H, connect an AC voltmeter
across wires #14 and #28.
9. Reconnect AC power to the unit.
10. Start the unit.
11. At the ignition trial cycle 120VAC should be
observed on the AC voltmeter.
12. If 120VAC is observed on the voltmeter,
replace the safety shut-off valve actuator.
13. If 120VAC is not observed on the AC
voltmeter, disconnect AC power to the unit.
14. Disconnect the 9 pin connector from the
control panel, and remove the cover from
the AC wiring box.
15. Referring to system schematic 161413 in
Appendix H, locate wires #14, #28 and #27
and check each for continuity.
16. Check each wire for loose connectors at the
safety shut-off valve end. Check wires #28
and #27 for loose connectors in the KC1000
AC wiring box
17. Check the pin on wire #9 at the 9 pin
connector end, for proper insertion or wear.
18. Make any necessary repairs.
19. If all wires show continuity and all
connections are okay, reconnect wires #14,
#28 and #29 to the safety shut-off valve and
wires #28 and #29 to their proper locations
in the AC wiring box.
20. Replace the cover plates on the safety shut-
off valve actuator and the AC wiring box.
21. Reconnect the 9 pin connector to the control
panel ensuring that it locks into place.
22. Reconnect AC power to the unit and Start
the unit.
23. If the safety shut-off valve still does not
open, proceed to section 8.7.8
24. Be sure to return the safety shut-off valve to
its original position and replace all electrical
cover plates.
8.5.4 SPARK IGNITOR
1. Disconnect AC power to the unit.
2. Remove the spark ignitor as per Section 7.2
of this manual.
3. Inspect the ignitor for signs of erosion.
4. Replace the ignitor if eroded.
5. Check for carbon build-up on the ignitor
.
6. If there is carbon carbon build-up, on the
ignitor, the combustion calibration settings
must be checked as per Section 4. If the
spark ignitor is not eroded, it may be cleaned
and reused.