AERCO BMK 3.0 LN Dual-Fuel Series Gas Fired Low NOx Boiler System - Manual (Page 74)

TROUBLESHOOTING
8-12
8.2 ADDITIONAL FAULTS WITHOUT SPECIFIC FAULT MESSAGES
Refer to Table 8-2 to troubleshoot faults which may occur without a specific fault message being displayed.
TABLE 8-2. BOILER TROUBLESHOOTING WITH NO FAULT MESSAGE DISPLAYED
OBSERVED INCIDENT PROBABLE CAUSES CORRECTIVE ACTION
Hard Light-Off 1. Staged Ignition Ball Valve closed.
2. Clogged/damaged Ignitor-Injector
(Figure 8-2).
3. Defective Staged Ignition Solenoid
(Figure 8-2)
1. Open the Staged Ignition 1/4” Ball Valve on the downstream side
of the Natural Gas SSOV (see Figure 8-1).
2. Disconnect and inspect gas injector to ensure it is not clogged or
damaged.
3. Close the 2” Shutoff Valve and the Staged Ignition 1/4” Ball
Valve on the downstream side of the Natural Gas SSOV (see
Figure 8-1). Start the unit and listen for a “clicking” sound that
the Staged Ignition Solenoid makes during Ignition Trial. If
“clicking” sound is not heard after 2 or 3 attempts, replace the
Staged Ignition Solenoid.
Fluctuating Gas Pressure 1. Gas pressure going into unit is
fluctuating.
2. Damping Orifice not installed.
1. Stabilize gas pressure going into unit. If necessary, troubleshoot
Building Supply Regulator.
2. Check to ensure that the Damping Orifice is installed in the
Propane SSOV, or Natural Gas SSOV depending on the type of
fuel being used (Figure 8-3).
Air/Fuel Valve “hunting” at 80%
Valve Position
1. IGST and Power Supply Boards in
Control Box are outdated.
1. Check to ensure that the IGST and Power Supply Boards are
Rev. E or higher.