Well, having left the printer on overnight to knock out an urgent print for a friend, I’ve discovered that, it’s a little on the noisy side!
The Wanhao D9 has FOUR fans! (yep, FOUR)
One 60x60x15mm fan in the power supply and Three 40x40x10
Two of these…AAA HZHZ 4010 MS 24V DC 0.10Amp fans
One on the extruder, right by the number 7, top yellow arrow
This one is the fan that cools the extruder block