We use thermistor from old E3D V6 hotend.
Klipper config is :
[temperature_fan chamber]
pin: PD13
max_power: 1.0
shutdown_speed: 0.0
kick_start_time: 5.0
cycle_time:0.01
off_below:0.1
sensor_type: NTC 100K beta 3950
sensor_pin: PF5
min_temp: 0
max_temp: 70
target_temp: 35.0
control: watermark
gcode_id: C
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