A.O. Smith Cyclone XL 100 Series, Руководство по обслуживанию

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9
SEQUENCE OF OPERATION FLOW CHART SEQUENCE OF OPERATION FLOW CHART
YES NO
120 V Recirculator
is energized
24 Volt Gas Valve
de-energized
Inter-Purge cycle
24 Volt Gas Valve
de-energized
Retries up to
two more times
Post-Purge cycle
Control System
Locks Out
“Ignition Failure”
Fault Msg is
displayed
Water heater goes
into standby mode
If tank temperature drops below Operating Set Point minus
Differential setting a heating cycle is activated
Spark Ignition Transformer is energized
24 Volt Gas Valve is energized
gas flows to Main Burner
Is flame sensed at the Main Burner?
(control system monitors the flame sensor)
Control System Locks Out
Displays Fault Msg
NO
Combustion Blower is energized
Pre-Purge cycle
Seqeence is shown with Enable/Disable Switch in the Enable position
Control System performs diagnostic checks.
Normal state of all pressure switches, the flow switch, and
the ECO are checked.
Pressure Switches and the ECO are verified closed.
Water is heated to
set point
120 V Recirculator is
de-energized after
5-second delay
Firere 7. Seqeence of Operation Flow Chart