72
1.4 Sequence of Operation
Operational State
User Interface Display
Explanation
If
fl
ame detected before Gas Valve opens
during ignition boiler will lockout.
Please refer to troubleshooting guide.
Gas Valve energized to deliver air/fuel to
burner.
If
fl
ame undetected after 3 seconds boiler
will de-energize Gas Valve and enter post
purge mode for 30 seconds.
Ignition attempted 5 times before
lockout.
Boiler will run provided all operational
and safety devices are within limits
Refer to for more information.
Control module adjusts
fi
ring rate
according to heating demand. When
Boiler detects demand met, will enter
post purge mode then standby mode.
If simultaneous demand for Central Heat
and DHW, boiler will enter DHW Priority
Mode.
Priority mode limits amount of time
boiler can run in DHW mode to meet CH
demand.
Max DHW Priority Time setting
determines maximum time allowed for
DHW heating mode.
Please refer to section Appendix A section
1.5 for more information.
Flame
Detected?
Gas Valve
Energized
Flame
Detected?
Heat Demand
Met?
DHW
Priority
Mode
Simultaneous
DHW + CH
Demand?
No
Yes
No
Yes
See Max DHW
Priority Time
Setting
No
After 2 seconds
After 3 seconds
No
30 second
post purge
Yes
Yes
Lockout
Error A21
Note:
5 Ignition
trials,
then
Lockout A01
APPENDIX A - CONTROL MODULE
Summary of Contents for DKVLT-050
Page 47: ...47 13 TROUBLE SHOOTING ...
Page 51: ...51 13 TROUBLE SHOOTING ...
Page 53: ...53 13 TROUBLE SHOOTING ...
Page 62: ...62 Supply Water Temperature Sensor Resistance Chart 13 TROUBLE SHOOTING ...
Page 64: ...64 14 WIRING DIAGRAM 14 1 Connection Diagram 050 075 100 150 200 MBH ...
Page 83: ...83 NOTES ...
Page 84: ...ECR International Inc 2201 Dwyer Avenue Utica NY 13501 web site www ecrinternational com ...