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Table 6. Smart Hub Parameters
Parameter
(In alphabetical
order)
Description
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
•
Standard
is a moderate gain suitable for nearly all installations.
•
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.
•
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
Cooling Step
Change PI Gain
(Lennox Variable
Capacity Outdoor
Units)
Step change gains deal with set point changes and affects how fast the system reaches the next set point.
Options are
less aggressive
,
standard
and
more aggressive
. Default is
standard
.
Modulating
Cooling Steady
State PI Gain
(Lennox Variable
Capacity Outdoor
Units)
Steady state gain controls the demand when the system is not responding to a sensed temperature change away from the iComfort thermostat setting.
Options are
less aggressive
,
standard
and
more aggressive
. Default is
standard
.
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
thermostat. (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 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: Adjustment to
the thermostat setting).
Options are
less aggressive
,
standard
and
more aggressive
. Default is
standard
. Recommend not changing this setting.
Modulating HP
Heating Cycles
Per Hour
(Lennox Variable
Capacity Heat Pumps)
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 thermostat. (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 3 to 6 cycles. Default is four cycles. Adjustments are in increments of 0.5 cycles.
Modulating HP
Heating Step
Change PI Gain
(Lennox Variable
Capacity Heat Pumps)
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 thermostat
setting).
Options are
less aggressive
,
standard
and
more aggressive
. Default is
standard
. Recommend not changing this setting.
Modulating HP
Heating Steady
State PI Gain
(Lennox Variable
Capacity Heat Pumps)
Steady state gain controls the demand when the system is not responding to a sensed temperature change away from the thermostat setting.
Options are
less aggressive
,
standard
and
more aggressive
. Default is
standard
. Recommend not changing this setting.
