User Manual Ultrean AF0302 Air Fryer

I did not receive a user manual.

No, there is no volume control.

For 3 minutes on the temperature the food is to be prepared

I believe so... I think I remember reading in the instruction booklet that it was PFOA free. Im not 100% sure however Im like 90% sure.

Yes, you should pre-heat the air fryer 5 minutes before putting your food in the air fryer and setting cook time. This information is in the manual.