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continuously after a control action. This feature is useful for thermostat models with
multiple fan speeds.
•
Fan Mode can be toggled between AUTO or CONTINUOUS by using the FAN button on
the thermostat (user) or BACnet object [MSV0] Fan Mode (BACnet supervisor). By
default, this value is set to “Auto(1)”, the AUTO icon is displayed, and the fan will be
controlled automatically. To put the fan in CONTINUOUS mode set to “Low(2)” this will
cause the fan to run continuously (no AUTO icon is displayed). Fan icon spinning when
fan is active. Optionally, the FAN button can be locked to limit user access to this feature
or the BACnet supervisor can be programmed to default the thermostat to certain state at
the end of an occupancy cycle.
Short Cycle and Maximum Cycles per Hour
•
There are short cycle and maximum cycles per hour protection for both cooling and heating
modes [AV23 – 26] Cooling Short Cycle Delay, Cooling Maximum Cycles per Hour and
Heating Short Cycle Delay, Heating Maximum Cycles per Hour.
•
The short cycle time (in minutes) will determine the minimum on time and minimum off time
of each stage before changing its state. The default setting is 3 minutes.
•
Maximum cycles per hour will count the number of cycles in an hour. When the cycle count
reaches the maximum cycles in an hour, it won’t allow additional cycles until the next hour.
•
When a stage change is pending due to a Short Cycle Delay or a Maximum Cycle count,
the Clock icon
) will appear on the LCD.
•
To disable short cycle checking, set the short cycle to 0 minutes.
NOTE:
Do not use this
value unless the heating and cooling equipment is equipped with an internal timer.
Damage to equipment may occur.
Floating Deadband
•
The Heat and Cool temperature setpoints could be “attached” together. This means that
as one setpoint is adjusted and “hits” against the deadband region, it will “push” the
deadband region and the other setpoint along the temperature setpoint axis to allow for
adjustment while maintaining the configured deadband. If the setpoint is adjusted back the
other way, it will “pull” the deadband region and the other setpoint along the temperature
setpoint axis.
Minimum Cooling Setpoint and Maximum Heating Setpoint
•
Minimum Cooling Setpoint will be confined by set point low limit plus dead band and
Minimum cooling setpoint [AV-39] default: 18
℃
/ 65
℉
•
Maximum Heating Setpoint will be confined by set point high limit minus dead band and
Maximum heating setpoint [AV-40] default: 25
℃
/ 77
℉