AERCO BMK 3.0 LN Dual Fuel 2007 - Manual (Page 71)

TROUBLESHOOTING
8-11
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 Gas Injector
(Figure 8-2).
3. Defective Staged Ignition Solenoid
(Figure 8-2)
1. Open the 1/4” Ball Valve on the downstream side of SSOV #2
(Fig. 8-1).
2. Remove and inspect Gas Injector to ensure it is not clogged or
damaged.
3. Close the 2” Shutoff Valve and the 1/4” Ball Valve on the
downstream side of SSOV #2 (Fig. 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
downstream SSOV #1 (Propane) or upstream SSOV #2 (Natural
Gas) depending on the type of fuel being used (Figure 8-3).
Air/Fuel Valve “hunting” at 80%
Firing Rate
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Control Box are outdated.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.