BMK 5000-6000 Boiler OPERATION-SERVICE-MAINTENANCE GUIDE
SECTION 5 – TROUBLESHOOTING GUIDE
OMM-0124_0A
AERCO International, Inc.
•
100 Oritani Dr.
•
Blauvelt, NY 10913
Page
69
of
136
GF-208
Ph.: 800-526-0288
05/02/2017
TABLE 5-1: BOILER TROUBLESHOOTING PROCEDURES
FAULT
INDICATION
PROBABLE CAUSES
CORRECTIVE ACTION
INTERLOCK
OPEN
1.
Interlock jumper not installed or removed.
2.
Energy Management System does not have unit
enabled.
3.
Device proving switch hooked to interlocks is not
closed.
1.
Check for a jumper properly installed across the interlock terminals
in the I/O box.
2.
If there are two external wires on these terminals check any Energy
Management system to see if they have the units disabled (a jumper
may be temporarily installed to see if the interlock circuit is
functioning).
3.
Check that proving switch for any device hooked to the interlock
circuit is closing and that the device is operational.
LINE VOLTAGE
OUT OF PHASE
1.
Line and Neutral switched in AC Power Box.
2.
Incorrect power supply transformer wiring.
1.
Check hot and neutral in AC Power Box to ensure they are not
reversed.
2.
Check transformer wiring, in AC Power Box, against the power box
transformer wiring diagram to ensure it is wired correctly.
GAS
PRESSURE
FAULT
(Due to Low Gas
Pressure)
1.
Incorrect supply gas pressure.
2.
Defective Low Gas Pressure switch.
1.
Measure NATURAL GAS pressure upstream of the SSOV
Actuator(s) with the unit firing. For FM gas trains, ensure it is
between 4.0” W.C. and 14” W.C. (1.0 and 3.5 kPa)
. For DBB gas
trains, ensure it is
between 4.5" W.C. and 14” W.C. (1.1 and 3.5
kPa)
.
2.
Measure NATURAL GAS pressure at the Low Gas Pressure switch.
If it is
greater than 2.6” W.C. (650 Pa)
, measure continuity across
the switch and replace if necessary.
LOW WATER
LEVEL
1.
Insufficient water level in system.
2.
Defective water level circuitry.
3.
Defective water level probe.
1.
Check system for sufficient water level.
2.
Test water level circuitry using the C-More Controller front panel
LOW WATER TEST
and
RESET
buttons. Replace water level
circuitry if it does not respond.
3.
Check continuity of probe end to the shell, change probe if there is
no continuity.
MODBUS
COMMFAULT
1.
Unit not seeing information from Modbus network.
1.
Check network connections. If fault persists, contact qualified
Service Personnel.
O2
PERCENTAGE
LOW
1.
Dirty air filter..
2.
Blockage in the inlet air duct.
3.
Gas pressure too high.
1.
Remove air filter and clean per section 7.9.
2.
Inspect all sections of the duct for foreign materials.
3.
Measure the gas pressure between the SSOV and the Air/Fuel Valve.
It
should be 7.9” W.C. ± 0.2” W.C. (2.0 kPa ± 50 Pa)
.
