AERCO BMK 1.5 LN Dual Fuel Feb 2013 - Manual (Page 75)

CHAPTER 6: SAFETY DEVICE TESTING
PR2: 05/09/12 Page 75 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
3. Refer to Figure 6-1a or 6-1b and locate the Natural Gas SSOV.
4. Remove the cover from the SSOV by loosening the screw shown in Figure 6-4. Lift off
the cover to access the terminal wiring connections.
5. Disconnect wire #148 from the SSOV to “open” the proof of closure switch circuit.
6. The unit should fault and display SSOV SWITCH OPEN.
7. Replace wire #148 and press the
CLEAR button.
8. Set the ON/OFF switch to ON to start the unit.
9. Remove the wire again when the unit reaches the purge cycle and PURGING is
displayed.
10. The unit should shut down and display SSOV FAULT DURING PURGE.
11. Replace the wire on the SSOV and press the
CLEAR button. The unit should restart.
ACTUATOR
COVER
SCREW
SSOV
ACTUATOR
COVER
Figure 6-4: SSOV Actuator Cover Location
6.12 PURGE SWITCH OPEN DURING PURGE
The Purge Switch (and Ignition Switch) is located on the Air/Fuel Valve. To check the switch,
proceed as follows:
1. Set the unit’s ON/OFF switch to the OFF position. Place the unit in manual mode and
set the valve position between 25% and 30%.
2. Remove the Air/Fuel Valve cover by rotating the cover counterclockwise to unlock it
and then lift up (see Figure 6-5).
3. Remove one of the two wires (#171 or #172) from the Purge Switch (Figure 6-6).
4. Initiate a unit start sequence.
5. The unit should begin it’s start sequence, then shut down and display PRG SWITCH
OPEN DURING PURGE.
6. Replace the wire on the Purge Switch and depress the CLEAR button. The unit should
restart.