PEERLESS GM Installation, Operation & Maintenance Manual page 20

ELECTRICAL
Figure 6.4: Connection and Schematic Diagram, Intermittent Ignition, Natural Gas
SEQUENCE OF OPERATION, INTERMITTENT
IGNITION:
1. Thermostat calls for heat.
2. Limit senses boiler water temperature. Prevents
operation until water temperature falls approximately
15°F (9°C) below the cut-out temperature.
3. Automatic vent damper (if used) opens. Damper
must be in open position when appliance main
burner(s) is operating.
4. Gas valve energizes.
a. Igniter on.
b. Pilot gas on, igniting pilot.
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5. Pilot flame detected.
a. Igniter off.
b. Main gas on, igniting main burners.
Note: If pilot flame is not detected within 30 seconds,
the igniter is turned off for 30 seconds, and then turned
back on. If the pilot is not detected within 30 seconds,
the igniter and pilot gas are turned off for 5 minutes.
The sequence then resumes at Step 4a.
6. Call for heat ends.
a. Pilot and main gas off, extinguishing pilot and
main burners.
b. Automatic vent damper (if used) closes.