Honeywell EXCEL 5000 User Manual page 179

EXCEL CARE CONTROL ICONS
Optimum Start
with Adaptation
the heating curve (default slope 1.6) and further modifies it with room temperature
and room temperature setpoint of the time schedule.
Heavy load — if the load on the system was so high that even an occupancy start
time minus P5 and a maximum flow temperature setpoint P15 would be insufficient,
then software calculates an even earlier start time.
During the pre-heat period, the TOat causes the flow temperature setpoint to vary. If
room temperature rises above the time program setpoint, the statement resets the
flow temperature setpoint accordingly. At occupancy start, EOH3 calculates the flow
temperature setpoint using the heating curve.
If the room temperature is below the setpoint at occupancy start time, the statement
increases the flow temperature setpoint. This effect on the flow temperature setpoint
continues for a period of 30 minutes after occupancy start. After this time, EOH3
calculates the flow temperature setpoint using the heating curve.
EOH3 software includes HCA functions. For automatic adaptation of the heating
curve (flow temperature vs. outside air temperature):
• Connect a room temperature sensor
• Set the room temperature setpoint greater than 18 °C
• Enable adaptation (P12 = 1)
• Ensure the following conditions:
- Average TOat must be less than 15°C
- Adaptation must occur at least three times before you can alter the defaults for
the basic setting of the heating curve
At the calculated stop time, the statement resets the flow temperature setpoint to
zero and changes the digital output Start (YD2) to logic 1. Start (YD2) remains at
logic 1 until optimum start (next day or later).
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ALPHABETIC REFERENCE
74-5577–33 (US)
EN2B-0184 GE51 R0518 (Europe)