ISC-0027BW Initial Fan Start Temp

With the grill and meat probes inserted and the controller connected to wifi, at what temp difference should the fan start, i.e., grill set to 225 deg and grill temp reads 75 deg at start? Should the controller detect and start fan? Does it start at 100% and ramp down as temp increases or run max speed until temp met? i would expect variable fan speed. Just bought, haven’t used yet.

Normally, when the temperature is close to the target value, it will turn to PID calculation, which will reduce the wind speed according to the change of temperature.