OMM-0153_E
• 5/11/2023 Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST Page 36 of 124
CENTURION Installation, Operation & Maintenance Manual
SECTION 4: START SEQUENCE
Figure 4-3: Blocked Inlet and Blower Proof Switch
6. On the Ignition Sequence screen, the
Purging
indicator turns grey while purging is
underway and
Purge Timer
displays the purge cycle’s elapsed time in seconds.
Figure 4-4: Ignition Sequence Screen
–
Purging
7. Upon completion of the purge cycle, the Edge Controller initiates an ignition cycle and
the following events occur:
a) The Air/Fuel Valve rotates to the ignition position and closes the ignition switch. The
Dial on the Air/Fuel Valve (Figure 4-5) will read between
25
and
35
to indicate that
the valve is in the low fire position.
b) The Spark Cleaning cycle begins (default duration = 7 sec.) and the Ignition
Sequence screen’s
Spark Cleaning
indicator turns grey. This cycle turns on the
ignition transformer to produce a spark (with no gas flowing) to remove moisture and
carbon buildup from the spark element. For the duration of this cycle, the Controller
displays the
Cleaning Igniter
status message.
c) Following the Spark Cleaning cycle, power is applied to the gas Safety Shut-off
Valve (SSOV). When the SSOV indicates the Gas Valve is OPEN (POC), the
Ignition Sequence screen’s
Ignition
indicator turns grey.
d) If no spark is present 3 seconds into the ignition trial, the Controller aborts the
Ignition Cycle and shuts down the Water Heater. Refer to
in this
guide for guidance if this occurs.
BLOCKED INLET
SWITCH
BLOWER PROOF
SWITCH
