AERCO BMK 1.5 LN Dual Fuel Feb 2013 - Manual (Page 73)

CHAPTER 6: SAFETY DEVICE TESTING
PR2: 05/09/12 Page 73 of 162
Benchmark 1.5LN Dual-Fuel Low NOx Boiler
Operation and Maintenance Manual
OMM-0041_0C
GF-121
AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 • Ph: 800-526-0288
8. Once flame is proven, close the Manual Shut-off Valve located between the SSOV and
the Air/Fuel Valve (Figures 6-1a and 6-1b).
9. The unit should shut down and execute an IGNITION RETRY cycle by performing the
following steps:
(a) The unit will execute a shutdown purge cycle for a period of 15 seconds and display
WAIT FAULT PURGE.
(b) The unit will execute a 30 second re-ignition delay and display WAIT RETRY PAUSE.
(c) The unit will then execute a standard ignition sequence and display WAIT IGNITION
RETRY.
10. Since the manual gas shutoff valve is still closed, the unit will fail the ignition retry
sequence. Therefore, it will shut down and display FLAME LOSS DURING IGNITION
following the failed ignition retry cycle.
11. Open the valve previously closed in step 8.
12. Press the CLEAR
button. The unit should restart and fire.
Figure 6-3: Manual Gas Shut-Off Valve Location
NOTE
The Blocked Inlet Switch and Blower Proof Switch each may be
assembled to the Air/Fuel Valve differently than shown in Figure 6-3
on some units, but function and testing is the same in any case.
6.10 AIR FLOW FAULT TESTS
These tests check the operation of the Blower Proof Switch and Blocked Inlet Switch shown in
Figure 6-3.
BLOWER
PROOF
SWITCH
BLOCKED
INLET
SWITCH
AIR/FUEL
VALVE
GAS TRAIN
ASSEMBLED
HERE
BLOWER
STAGED
IGNITION
ASSEMBLY