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If entering adjust ratio mode while the burner is in AUTO (modulating) the displayed setpoint will be
the closest setpoint to the actual firing rate of the burner. If the calculated modulation point is
between two setpoints, the burner will move to the lower setpoint.
While in adjust ratio mode and in STANDBY, s01, the burner can be made to turn on and will cycle
through its normal sequence.
1. During the purge and ignition sequence the user will be able to view all programmed setpoints for
that profile. No change to any setpoint can be made when below a03.
2. Upon reaching the AUTO state, s16, the modulation rate or servo positions will move to the point
corresponding with the displayed adjust ratio setpoint.
3. Upon reaching AUTO, s16, if the displayed adjust ratio setpoint is a00, a01 or a02, the burner will
hold at a03 (low fire). The user has the ability to move through all programmed setpoints, forward
or backward, using the NEXT or BACK keys. Pressing the NEXT key will not allow the user to
exceed the highest commissioned setpoint.
4. Only setpoints a03 and above can be adjusted, the user can move below a03 but will not be able to
make any adjustments.
5. As the user moves through the setpoints the servo positions will also move to track the current set-
point selected. However, if the user moves below a03, the servos will remain at their a03 posi-
tions.
6. The user is inhibited from making any servo adjustments prior to the servos reaching the selected
setpoint.
7. If a VFD is used in the current profile, an additional check is performed on the FUEL servo only
to ensure that there are no non-linear setpoints entered. This means that no setpoint will be
allowed that would make the servo movement change direction as the setpoint number is
increased from a03 to the maximum setpoint entered. For example, if the user has entered 5.0 for
a03, 10.0 for a04, and 15 for a05, if the user was adjusting a04, no value below 5.1 or higher than
14.9 would be allowed for the FUEL servo since the a04 value is bounded by the a03 and a05 val-
ues. If a VFD is not used in a profile, the same linearity restriction applies but to the AIR servo
only not the FUEL servo.
During adjust ratio mode, the user can adjust each servo for that setpoint by using the MDFY/SAVE
key followed by the UP and/or DOWN keys and saved by the MDFY/SAVE key.
During adjust ratio mode, the modulation algorithm is ignored. That is, the firing rate or servo posi-
tions will be determined by the selected profile setpoint. This applies to setpoint a03 and above. If
the BACK is used to move below a03, the firing rate or servo positions will remain at a03.
While in Adjust Ratio, LOW FIRE and AUTO/MAN keypad states are ignored. The INFO as well as
the BURNER ON keys are active during adjust ratio mode.
If the current process variable's cut out is exceeded, the burner will shutdown, the burner on limit
switch can be opened to caused a burner shutdown, the BURNER ON key switch is pressed to cause
a burner shutdown, or lockout can occur to cause a burner shutdown. For all of the above the adjust
ratio procedure will remain in effect and revert back a00.
Exiting Adjust Ratio Mode
1. Pressing the C-MODE key forces all setpoints modified and saved to be transferred or saved to
permanent memory for this profile. The C-MODE LED will be extinguished.
2. On exiting adjust ratio mode, the passcode will be disabled.
BOILER EFFICIENCY
