85
The heating analog output opens to 100% when the freezestat is on.
Heating is enabled when:
•
The unit is running, and
•
The fan status is on, and
•
The unit is not cooling.
Economizer (optional):
The Room Controller measures the zone temperature and modulates the outside air
dampers to maintain the cooling setpoint. The Room Controller opens the outside air
dampers to at least a configurable minimum position to provide ventilation when the
room is occupied. The Room Controller closes the outside air dampers completely when
the freezestat is on.
The economizer is enabled when:
•
Outside air temperature is at least 3°F (1.5°C) less than the zone temperature, and
•
The outside air temperature is less than 70°F (21°C), and
•
Heating is not on.
The outside air dampers close when the unit is off. If the unit operates in the unoccupied
mode, the economizer operates as described in the occupied mode except that the
outside air damper minimum position is 0% open.
Two-position outside air dampers (optional) -
Used in place of Economizer when no outside air temperature sensor is present.
The outside air dampers open fully when:
•
The fan is running, and
•
The room is occupied.
The Room Controller closes the dampers completely when:
•
The fan is not running, or
•
The room is unoccupied, or
•
The freezestat is on.
The discharge temperature limit control (if present) limits the damper position if the
discharge temperature drops too low.
