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CP4B Room Thermostat
OS (Optimum Start Mode)
Boiler
Plus
(Continued)
PO 1 Operating Mode
(Normal / Optimum Start / TPI)
To achieve the target temperature when the program starts, the
thermostat will read:
1. The Room Temperature (RT)
2. The Setpoint Temperature (ST)
3. The Target Temperature Difference (TTD) is the difference
between the setpoint temperature and the room temperature .
The time (in minutes) that it will take to overcome (TTD) is called
Optimum Start Time (OST) and its maximum value is 3 hours = 180
mins. This is subtracted from the start time.
As the temperature increases the thermostat will recalculate the OST if
the temperature is increasing too quickly.
