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NOTE: Unoccupied cooling and heating
set points must be set within the cooling
set point high limit and the heating set
point low limit in order to control to the
proper set points.
Cooling Set Point Low Limit
Heating Set Point High Limit
These limits apply to both occupied and
unoccupied modes of operation. Both
limits have a range of 30.0° – 100.0°F
(-1.1° – 37 .8°C). The set point limits will
be applied to the active set points by
the UCM but will not restrict operator
entry of set points.
NOTE: These limits are allowed to cross
(i.e. the cooling set point low limit can be
greater than, less than, or equal to the
heating set point high limit).
The UCM will enforce these limits
regardless of the source of the active
set points.
Cooling Set Point High Limit
Heating Set Point Low Limit
These limits apply to both occupied and
unoccupied mode. Occupied and
unoccupied cooling and heating set
points are subject to high and low
limits. The cooling set point high limit
and the heating set point low limit
"cap" your unoccupied set points,
which directly impacts energy savings.
The upper level device is responsible
for preventing the resulting set points
from being crossed. This may happen if
the heating set point low limit is above
the cooling set point high limit. Having
the cooling set point high limit and the
heating set point low limit set to the
factory defaults (cooling high limit =
102°F , heating low limit = 43°F) should
prevent them from impacting field
operation.
20
UCM Programming
and Operation
Heat Offset
The set point has a range of 2° – 10°F
(1.1° – 5.6°C). When a zone sensor
thumbwheel set point is being used, the
cooling set point will equal the zone
sensor thumbwheel set point and the
heating set point will equal the zone
sensor set point minus the Zone
Sensor Heating Set Point Offset. The
offset will always be displayed and will
always be editable even if a zone sensor
set point is not being used.
Control Offset Value
The Control Offset has a range of 0° –
5°F (0° – 2.8°C). When Control Offset is
active, this value will be added to the
edited occupied cooling set point and
subtracted from the edited occupied
heating set point to determine the
active set points.
Note: The control-offset value will not
effect a zone sensor thumbwheel set
point.
Fan Control Set Point
The entry on this line determines when
a parallel fan will be turned ON and OFF .
If "Parallel fan control" has been edited
to "DEG" the fan control offset will be
entered as a temperature offset (2° –
10°F) which will be added to the heating
set point. If "Parallel fan control" has
been edited to "FLOW" this line will be
entered as a percent (0 to 100%) if the
unit is a VariTrane unit. The entry field on
this line will appear as "—" if the unit
does not have a parallel fan.
BP Failsafe Position
This setting only applies to VariTrac
Bypass mode of operation. If the CCP
stops communicating with the Bypass
Damper UCM for more than 60
seconds, the UCM will drive to the
failsafe position.
BP Command Position
This setting only applies to VariTrac
Bypass mode of operation. The CCP
uses this parameter to set the proper
position of the Bypass damper.
Maximum Flow/Position
This range is 10% to 100% of the unit's
cataloged CFM size. Cooling and
heating flow can be edited to zero.
Minimum Flow/Position
Although the UCM will read flow down
to 5% of cataloged, the range of MIN
FLOW settings is 0%, or 10% to 100% of
cataloged.
Min Heating Flow
The UCM will not drive its position/flow
below this value under normal operat-
ing conditions while in the HEAT mode
(warm air in the supply duct) or while it
is using local heat. The Min Heating
Flow value must be less than or equal
to the Maximum Flow value. If the Min
Local Heat Flow is enabled, then the
Min Local Heat Flow is used to deter-
mine the minimum position/flow
instead of the Min Heating Flow when
local heat is on.
Min Local Heat Flow
This input allows a separate heating
minimum flow set point to be used for
local reheat. When local reheat is on,
your active minimum flow can not be
less than your minimum local heat flow
set point.
VAV-SVX01B-EN
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