VENT MODE
In the DEADBAND mode, the unit is neither calling for heating or cooling during an OCCUPIED state. The
zone temperature will be between the activeHeatStpt (A188) and activeCoolStpt (A187). The damper will
modulate to maintain the minCoolFlowStpt (A227). If the unit includes a fan, see the Fan Control section
in Section 3.
SETPOINT MODIFIERS
The Occupied setpoints can be modified in several different ways. HVACModeCmd (A287) must be in
Auto.
• Slider Offset
o If a generic Zone Temperature sensor is wired to UI1, UI2 can be setup to take a 0-5k
potentiometer. The slider is enabled when binary setpoint SliderEnable (D95) is set to On.
The analog setpoint SliderSpanStpt (A138) value will determine the upper and lower
temperature range an end-user can set the sensor.
▪ For example, if SliderSpanStpt (A138) is set to 4, that will allow a +2 to -2 range
change for the heating and cooling setpoints. Let us say the occupied cooling
setpoint (is 72F (22C) and the heating setpoint is 70F(20C). When UI2 value is 0
ohms, the activeCoolStpt (A187) and activeHeatStpt (A188) will offset 2 degrees
down, so the activeCoolStpt (A187) will change to 70F(20C), and activeHeatStpt
(A188) will change to 68F(18C). When the UI2 value is 5k ohms, the occupied
activeCoolStpt (A187) and activeHeatStpt (A188) will offset 2 degrees up. Then
the activeCoolStpt (A187) will change to 74(24C), and the activeHeatStpt (A188)
will change to 72(22C).
• Standby Offset
o If the unit is scheduled OCCUPIED and has an occupancy sensor on an input. When no
occupancy is detected by the occupancy sensor after a set time, the occupied setpoints
will offset to their standby setpoints, determined by the standbyOffset (A146) analog
setpoint.
▪ For example, let us say the standbyOffset (A146) is set to 3 deg, and the cooling
setpoint is 72F(22C) and the heating setpoint is 70(20C). When no occupancy is
detected by the occupancy sensor, the activeCoolStpt (A187) will change by +3
deg and change to 75F(25C). The activeHeatStpt (A188) will change by -3 deg and
change to 67F(17C). Once there is occupancy detected, the cooling and heating
setpoints will revert to their occupied setpoints.
• Shed Offset
o If a value from 1-100% is sent to the netShedCmd (A310) analog point, the cooling and
heating setpoints will reset from their occupied setpoints to their standby setpoints on a
sliding scale.
▪ For example, at 50% shed, and the activeCoolStpt (A187) was 72F(22C), and
activeHeatStpt (A188) was 70F(20C), the new values will be 73.5F(23.5C) for
activeCoolStpt (A187), and 68.5F(18.5C) for the activeHeatStpt (A188). At 100%,
the cooling and heating setpoints will be equal to their standby setpoints.
CBT STAT
Note: CBT-STAT cannot be used to balance a VAV box.
If a CBT-STAT has been wired to the unit, the heating and cooling setpoints will be sent down to the CBT-
STAT display. The strategy will automatically detect if the CBT-STAT is present and use zone temperature
from the CBT-STAT and not UI1. On any mode change, the calculated setpoints will be sent down to the
CBT-STAT, overriding any user adjustment for that period. Users can adjust the setpoints during
occupied and unoccupied periods.
The CBTStatStptEnable (D164) digital setpoint can be used to lock out the ability of users to adjust the
stat. If the unit is in Shed Mode, the CBT-STAT will also be locked out.
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