AERCO BMK 2.0 LN Natural Gas (SN G-11-1861 and above) - Manual (Page 44)

Chapter 3
Benchmark 2.0LN Low NOx Boiler
GF-123
Operation Installation, Operation and Maintenance Manual OMM-0046_0E
Page 44 of 170 AERCO International Inc.● 100 Oritani Dr. ● Blauvelt, NY 10913. ● Ph: 800-526-0288 PR1 08/20/12
Figure 3-3: SSOV Location
4. Next, the blower proof switch on the Air/Fuel Valve (Figure 3-5) closes. The display will
show Purging and indicate the elapsed time of the purge cycle in seconds.
5. Upon completion of the purge cycle, the Control Box initiates an ignition cycle and the
following events occur:
(a) The Air/Fuel Valve rotates to the low-fire ignition position and closes the ignition switch.
The dial on the Air/Fuel Valve (Figure 3-6) will read between 25 and 35 to indicate that
the valve is in the low-fire position.
(b) The igniter relay is activated and provides ignition spark.
(c) The gas Safety Shut-Off Valve (SSOV) is energized (opened) allowing gas to flow into
the Air/Fuel Valve.
SSOV
GAS
INLET
TO AIR/FUEL
VALVE
MANUAL SHUT-OFF VALVE