P1S Chamber Fan controls?

What parameters control whether the Chamber fan comes on in a P1S? Can this be controlled in Bambu Studio? I couldn’t find any setting for it in the Cooling Section

Every setting is in the slicer’s advanced features section

temp of the bed determines it.
You can read it here and adjust it if necessary.

This is on a P1S not an X1

Sorry but I have a P1S, photo is bambu studio settings. (PC)

The chamber fan speed is set by the Filament Start G-Code in the Advanced tab of the Filament profile. It uses the bed temperature to decide which of several speeds to run the chamber fan. An example:

; filament start gcode
{if (bed_temperature[current_extruder] >55)||(bed_temperature_initial_layer[current_extruder] >55)}M106 P3 S200
{elsif(bed_temperature[current_extruder] >50)||(bed_temperature_initial_layer[current_extruder] >50)}M106 P3 S150
{elsif(bed_temperature[current_extruder] >45)||(bed_temperature_initial_layer[current_extruder] >45)}M106 P3 S50

The number after the S is the speed, with values 0-255. You can edit this and save as a user profile if you want.