State SBL100 199 NE - Manual (Page 25)

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8. If the Ignition Control does not sense the pilot flame during the
ignition trial period, the Ignition Control shuts the Pilot Gas Valve
and turns off the Spark Igniter. After 5 minute delay, a new trial for
ignition is initiated. This sequence continues until the unit lights
or “Call for Heat” is removed.
9. If the pilot flame is proved during the ignition trial period, the
Ignition Control will energize the main gas valve to start the
heating cycle. If the flame signal is lost during the heating cycle,
the Ignition Control shuts the Gas Valve and re-starts the ignition
process at step 5.
10. Once the unit is satisfied, the Thermostat will turn off the 24vac power
to the blower relay and the Ignition Control, and the unit will be in
standby mode until another call for heat is initiated by the thermostat.
See the flow chart on page 27 for more detailed information.
seQuenCe of operation
The following information will describe the Sequence of Operation
for this water heater.
1. Switch power on to unit.
2. Thermostat calls for heat.
3. blower power relay is energized to start the blower.
4. The blower pressure switch is closed, 24VAC power is applied to
the Ignition Control Module.
5. The Ignition Control performs diagnostic self check on system
components.
6. The Ignition Control begins the trial for ignition by turning on the
Spark Igniter and the Pilot Gas Valve.
7. The Ignition Control monitors the Flame Sensor during the ignition
trial period.
lighting & operating laBel
figure 23.