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If chilled water is used, the Room Controller measures the zone temperature and
modulates the chilled water valve to maintain the cooling setpoint.
The cooling analog output opens to 50% when the freezestat is on.
Cooling is enabled when:
•
The unit is running, and
•
The fan status is on, and
•
The unit is not heating.
Heating
If staged heating is used, the Room Controller measures the zone temperature and turns
on the heating as needed to maintain the heating setpoint. To prevent short cycling, the
heating stage has a 1-minute minimum runtime.
If hot water heating is used, the Room Controller measures the zone temperature and
modulates the heating analog output to maintain the heating setpoint.
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.