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Modulex Light Commercial Series
SECTION 6: Gas Supply and Piping
OMM-0158_A
• 6/28/2022 Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST Page
93
of
120
BCM (Boiler Communications Module) Fault Codes
The table below lists the fault codes and troubleshooting tips associated with the BCM.
FAULT CODE
DESCRIPTION
EFFECT
CORRECTION
RESET
HCM: 2
Low gas pressure
Gas Pressure Switch
-
NOT APPLICABLE.
HCM: 8
Low water pression
Water Deficiency
-
NOT APPLICABLE.
HCM: 9
Outer temperature
sensor
Outdoor sensor
Enabled but not
connected
Outdoor Reset not
available.
AUTOMATIC -
Outdoor Reset will
be available once
outdoor sensor is
connected.
HCM: 13
DHW Temperature
sensor
DOMESTIC HOT
WATER sensor fault
DHW service not
active
Check DHW sensor
and its resistance
using the
resistance/Temp
table); check the
sensor connections.
AUTOMATIC
HCM: 14
CH return sensor
Global return sensor
failure
All burners turned
OFF.
Check return sensor
or wiring.
AUTOMATIC
HCM: 17
Global frozen
Boiler pipe is frozen.
Flow sensor temp. is
36°F or less.
Ignition is inhibited.
Pump runs for 5 min
at max speed.
Carefully defrost
boiler.
AUTOMATIC - when
Flow sensor is
greater than 41°F.
HCM: 18
Global differential
temperature
Maximum Δ
-
temperature
protection.
Fault is detected if
[Global FlowSensor
–
Return Sensor] >
[Param 483 + 50°F].
Note: Referred
parameter is BCM
Param. 483
All burners turned
OFF and Pump ON at
maximum speed.
Check circulation,
check installation
AUTOMATIC - Fault
is cleared when
[Global FlowSensor
–
Return Sensor] <
Param 483.
Note: Referred
parameter is BCM
Param. 483
HCM: 19
Global overheating
High outlet
temperature. Flow
sensor temperature
> 203°F.
All burners turned
OFF and pump ON at
maximum speed.
Check Flow Sensor
or system pump.
AUTOMATIC - when
Flow sensor < 176°F.
HCM: 28
Chimney closed
Flue/Chimney
Obstruction
Ignition is inhibited.
Check flue/chimney
MANUAL
HCM: 29
Condense level
Water inside the
combustion
chamber.
Ignition is inhibited.
Check for water in
the exhaust manifold
AUTOMATIC
HCM: 30
Service parameters
Settings corrupted.
Ignition is inhibited.
Contact factory.
MANUAL - push
reset switch
HCM: 37
Parameters memory
BCM: Internal fault
Contact factory.
MANUAL
HCM: 38
Factory parameters
Settings corrupted
by electromagnetic
interference.
Ignition is inhibited.
Contact factory.
MANUAL - push
reset switch
HCM: 39
User parameters
Settings corrupted
by electromagnetic
interference.
None
Contact factory.
AUTO