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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
95
of
120
BMM (Burner Management Module) Fault Codes
The table below lists the fault codes and troubleshooting tips associated with the BMM.
CODE
DESCRIPTION
EFFECT
CORRECTION
RESET
BMM: 1
Overheat
thermostat
High Limit (STB)
Thermostat
activated.
All burners turned
OFF and pump ON at
maximum speed.
Check flow sensor thermal
connection to boiler.
MANUAL -
push reset
switch when
temperature
goes below
limit.
BMM: 4
Ignition failure
No flame detected at
burner start.
Burner control
lockout.
Check flame rod or combustion.
MANUAL -
push reset
switch or cycle
power.
BMM: 5
Flame lost
Flame loss during
run.
Ignition retry.
Check combustion and wiring.
MANUAL -
push reset
switch or cycle
power.
BMM: 6
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.
BMM: 10
Internal
failure
Internal failure.
Ignition is inhibited.
Contact factory for new BMM.
MANUAL -
cycle the
power.
BMM: 11
Unexpected
flame
Flame signal
detected before
ignition.
Ignition is inhibited.
Disconnect flame rod wire from
BMM. If problem goes away,
change flame rod and/or wire.
If problem does not go away,
change BMM.
MANUAL -
push reset
switch or cycle
power.
BMM: 12
CH flow
sensor
Flow sensor fault.
All burners turned
OFF.
Check flow sensor and its
resistance using the
resistance/Temp table); check
the sensor connections.
AUTOMATIC
BMM: 14
CH return
sensor
Return sensor fault.
-
NOT APPLICABLE
BMM: 15
Differential
temperature
Maximum Δ
-
temperature
protection.
Fault is detected if
Local FlowSensor
–
Return Sensor] >
[Param 483 + 50°F].
Note: Referred
parameter is BMM
Param. 483
All burners turned
OFF and Pump ON at
maximum speed.
Check the system installation.
AUTOMATIC -
Fault is cleared
when [Local
FlowSensor
–
Return Sensor]
< Param 483.
Note: Referred
parameter is
BMM Param.
483
BMM: 16
Frozen
Boiler pipe is frozen.
Flow sensor
temperature 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.