Maybe around 5 secs? If I have time, I might do a video.
That's way too fast, you can damage components at this rate. Look at typical thermal profiles in datasheets, preheating takes 2-3 min, then 10-30 sec soldering phase then cooling down about 1 min. Don't bring the fan too close until solder melts and components soak terminals in liquid solder.
For Pb/Sn solder I usually set 260-270C, do 1-1.5 min preheating from the bottom side of the board, then 10-30 sec from the top until solder melts and components settle.
Preheating can take more or less time depending on the board, I would suggest to keep heating the board until solder is just about to melt and you see it starting to change (matt<->gloss). Dry solder without flux may not change appearance, keep this in mind and watch time.