Trane LO - Manual (Page 67)

UNT-IOM-6 67
Tracer ® ZN.520
switch depending on the error. Fan speed increases as the space
temperature rises above the active cooling setpoint.
Table 21. Fan Configuration
Auto fan operation
Fan speed default
Heating Continuous Off
Low
Medium
High
CoolingContinuous Off
Low
Medium
High
Additional flexibility built into the controller allows you to enable or
disable the local fan switch input. The fan mode request can be either
hardwired or communicated to the controller. When both are present,
the communicated request has priority over the hardwired input. See
the following tables.
Table 22. Local fan switch disabled or not present
Communicated fan speed input
Fan operation
Off Off
Low Low
Medium Medium
High High
Auto (or not present)
Auto (fan runs at the default speed)
Table 23. Local fan switch enabled
Communicated
Fan switch (local) Fan operation
fan speed input
Off Ignored Off
Low Ignored Low
Medium Ignored Medium
High Ignored High
Auto Off
Low
Medium
High
Auto Off
Low
Medium
High
Auto (configured default, determined by heat/cool mode)
Table 24. Fan operation in heating and cooling modes