AERCO C-More Controls - Manual (Page 35)

C-MORE CONTROL PANEL OPERATION
5.4 START SEQUENCE
When the unit is in the Standby mode and all
pre-purge safety switches are closed, the
READY light above the ON/OFF switch will be
lit. When there is a demand for heat, the
following events will occur:
NOTE:
If any of the Pre-Purge safety switches (low
water level, high water temperature, high or
low gas pressure) are open, the appropriate
fault message will be displayed. Also, the
appropriate fault messages will be displayed
throughout the start sequence, if the
required conditions are not observed.
1. The DEMAND LED status indicator will light.
2. The unit checks the proof of closure switch
on the Safety Shut-Off Valve (SSOV) shown
in Figure 5-2.
Figure 5-2. Proof of Closure Switch
3. With all required safety switches closed, a
purge cycle will be initiated and the following
events will occur:
(a) Blower relay energizes and turns on
blower.
(b) Air/Fuel Valve rotates to the full-open
purge position and closes purge position
switch. The dial on the Air/Fuel Valve
(Figure 5-3) will read 100 to indicate that
the valve is full-open (100%).
(c) The FIRE RATE bargraph will show
100%.
NOTE:
The Air/Fuel Valves shown in Figures 5-3
and 5-5 are used on KC Series units.
Although slight physical differences exist
between the Air/Fuel Valves used on
Benchmark Series units, the valves are
functionally identical.
DIAL
(DETAIL “A”)
STEPPER
MOTOR
DETAIL "A"
100
Figure 5-3.
KC1000 Air/Fuel Valve In Purge Position
4. Next, the blower proof switch (Figure 5-4)
closes and the display will show Purging and
indicate the elapsed time of the purge cycle
in seconds. The normal (default) time for the
purge cycle is 7 seconds.
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