How does the “Setback differential” affect the room’s setpoint?

Normally, an on/off schedule activates the system and works to reach and maintain the setpoint of the room during the “in-range” period, which corresponds to the hours of normal operation. It turns off during the “out-of-range” periods, where only the zone antifreeze function remains active.

The “Setback differential” modifies the setpoint during the “out-of-range” period by adding (in cooling) or subtracting (in heating) its value from the zone temperature setpoint. This ensures that the room remains at a temperature that prevents significant deviation from the desired temperature and allows for a quick return to the desired setpoint once the “in-range” phase resumes. As a result, the overall energy consumption of the system is reduced.