Lennox iComfort S30 Installation And Setup Manual page 18

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Three*stage heat: 1st stage provides 60% of full capacity; 2nd stage provides
80% of full capacity; 3rd stage provides 100% of full capacity.
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Four*stage heat: 1st stage provides 35 or 40% of full capacity; 2
provides 60% of full capacity; 3rd stage provides 80% of full capacity; 4th stage
provides 100% of full capacity.
Load Tracking Variable Capacity
Load tracking variable capacity will smoothly track the load (sensible temperature
changes) up and down and adjust the furnace heating rate both ways.
Variable Capacity
Variable capacity only tracks the load upward (rising temperature). Variable
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capacity uses the iComfort S30 stage differentials but not stage timers.
NUMBER OF GAS HEATING STAGES
This is applicable to the SLP98V only. Number of selectable stages when Gas Heat
Control Mode is set in "Staged" mode. Options are 1 through 4. Default is 4.
UNDERSTANDING MODULATING STEP CHANGE AND
STEADY STATE PI GAINS
Each of these terms has a multiplier (or gain) associated with it called the
proportional gain and the integral gain respectively and affect responsiveness and
stability
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Standard is a moderate gain suitable for nearly all installations.
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More Aggressive is a set of slightly higher gains that will make the system
more responsive to changes, and will try harder to stay on the set point. This
setting may cause some systems to oscillate.
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Less Aggressive is a set of slightly lower gains that will make the system less
responsive and help to stabilize an oscillating system by sacrificing a small
amount of time to set point.
None of the above options will cause the system to end a call if the demand for
heating or cooling remains above the minimum capacity of the system since the
algorithm is designed to find the demand that allows the system capacity to exactly
match the house heating or cooling loss, creating a balance and constant
temperature.
MODULATING GAS HEATING STEADY STATE PI GAIN (SLP98V ONLY)
This is applicable to the SLP98V only. Steady state gain controls the demand when
the system is not responding to a sensed temperature change away from the
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iComfort S30 setting.
Options are Less Aggressive, Standard and More Aggressive. Default is Standard.
Recommend not changing this setting.
MODULATING GAS HEATING STEP CHANGE PI GAIN (SLP98V ONLY)
This is applicable to the SLP98V only. Step change gains deal with set point
changes and affects how fast the system reaches the next set point (Example:
nd
stage
Adjustment to the iComfort
Options are Less Aggressive, Standard and More Aggressive. Default is Standard.
Recommend not changing this setting.
MODULATING GAS HEATING CYCLES PER HOUR (SLP98V ONLY)
This feature is activated when the structure BTU load is less than the minimum
Heat Pump heating capacity of the outdoor unit. The system will be cycled "ON"
and "OFF" at the selected cycles per hour to maintain the settings of the iComfort
S30. (This governs how many cycles per hour the system will try to run when it
needs to run at less than minimum capacity)
Range is 4 to 10 cycles. Default is 6 cycles. Adjustments are in increments of 0.5
cycles.
MODULATING HP HEATING STEADY STATE PI GAIN (XP20 AND XP25)
Steady state gain controls the demand when the system is not responding to a
sensed temperature change away from the iComfort
Options are Less Aggressive, Standard and More Aggressive. Default is Standard.
Recommend not changing this setting.
MODULATING HP HEATING STEP CHANGE PI GAIN (XP20 AND XP25)
Step change gains deal with set point changes and affects how fast the system
reaches the next set point (Example: Schedule change or adjustment to the
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iComfort S30 setting.
Options are Less Aggressive, Standard and More Aggressive. Default is Standard.
Recommend not changing this setting.
MODULATING HP HEATING CYCLES PER HOUR (XP20 AND XP25)
This is applicable to the XP25 only. This feature is activated when the structure
BTU load is less than the minimum Heat Pump heating capacity of the outdoor unit.
The system will be cycled "ON" and "OFF" at the selected cycles per hour to
maintain the settings of the iComfort
hour the system will try to run when it needs to run at less than minimum capacity)
Range is 3 to 6 cycles. Default is 4 cycles. Adjustments are in increments of 0.5
cycles.
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S30 setting).
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S30 setting.
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S30. (This governs how many cycles per
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