Benchmark Platinum-Edge: Operation-Service Manual
SECTION 9 – AERTRIM OPERATION
OMM-0137_D • GF-211
•
7/16/2019
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9.4 AERtrim O
2
SENSOR AUTO CALIBRATION
AERtrim includes an automatic O
2
sensor calibration feature, which helps maintain oxygen
sensor readout accuracy.
When sensor calibration occurs, the controller starts the O
2
Cal Purge for 40 seconds (55
seconds on the BMK 6000) in order to remove residual combustion fumes. Once purged, the
Controller reads the oxygen level of ambient air used for purging and calculates a calibration
offset between -3 and +3. The offset is applied to correct the sensor reading to the expected air
O
2
% level of 20.9%. If the calculated offset is more than ± 3%,
O
2
Warning Service Required
message is displayed, and the trim function is disabled.
Auto Calibration occurs only when the unit is in Standby mode.
For example, if the time
and day for an auto calibration passes, the Controller will wait for the boiler to cycle off and go
into
Standby
mode before executing the sensor calibration function.
If desired, a calibration can be initiated by enabling the
Auto Calibrate Now
toggle on the
Controller’s
Oxygen Sensor
screen (
Main Menu
Calibration
Input/Output
Oxygen
Sensor
).
Auto Calibration
is disabled by default but is enabled during AERtrim activation (see Section
9.2, above). Calibration frequency and time adjustments can be modified from the
Auto Cal
Freq
and the
Auto Cal Time
setting, available on the Controller’s
AERtrim Settings
screen (go
to:
Main Menu
Advanced Setup
Performance
AERtrim
AERtrim Settings
).
