BMK 750-3k Platinum Boiler OPERATION, SERVICE, and MAINTENANCE GUIDE
SECTION 4 – AERTRIM OPERATION
Page
50
of
178
AERCO International, Inc.
•
100 Oritani Dr.
•
Blauvelt, NY 10913
OMM-0116_0A
03/15/2017
Ph.: 800-526-0288
GF-201
4.7 AERtrim MAINTENANCE and TROUBLESHOOTING
The AERtrim system, which maximizes blower efficiency, depends on the O
2
sensor. The
AERtrim system needs only minimal maintenance. It is recommended that you
inspect the
oxygen sensor
for accuracy
every 12 months
by comparing it to a sensor reading from a
properly calibrated flue analyzer. This is strongly advised because contaminated air or gas
supplies may cause impurity buildup and shift the calibration point. An offset value of ±3% can
be entered in the Trim menu to correct the reading during manual calibration. If the sensor has a
large amount of offset, a replacement may be required soon.
Occasional software updates to the device may be required. See TID-0156 for sensor
replacement instructions and the software update procedure.
The C-More does not display a message when O
2
levels are within the target range. However, if
O
2
levels fall outside the target range, one of the messages listed in Table 4-2 will be displayed
when you view the
Trim State
menu item in the
O2 Trim
menu.
Table 4-2: AERtrim GENERAL WARNINGS
WARNING
CAUSE
POSSIBLE SOLUTIONS
O2 PERCENTAGE LOW
O
2
Levels less than 2% for more than
30 seconds {auto-reset when valve
comes back in range}
Dirty filter or poor combustion
calibration – recalibrate unit
O
2
Offset too low – Increase
Offset value
Bad Sensor-Replace
O2 SENSOR
MALFUNCTION
O
2
Levels less than -4% or more than
24% for more than 10 seconds {manual
clearing of this fault is required}
Bad Sensor-Replace
Communication Issue – check
wires and connections
WARNING 02 LEVEL
HIGH
O
2
Levels > 9% and < 24% for more
than 30 seconds {auto-reset when
value comes back in range}
Gas Pressure Regulator or Air
Blower Problem, or bad
Combustion Calibration
O
2
Offset too high
Bad Sensor-Replace
O2 SENSOR OOR
MAINT REQUIRED
(OutOfRange)
Sensor auto calibration offset required
is more than ±3%
Reset Unit-Recalibrate Sensor
Bad Sensor-Replace
Bad ECU-Replace (Rare)
O2 WARNING SERVICE
REQUIRED
If the O
2
level is outside of its limits for
more than 5 minutes.
For example:
1) Reading < Lower Limit
& Blower Voltage = BV Limit
OR
2) Reading > Upper Limit
& Blower Voltage = BV Limit
Gas Supply, Air Filter, or Air
Blower issue
Bad Sensor-Replace
