Hello ! First please excuse me for my english. I mounted my e3d-v6 hot-end. I have a question about the 30x30 fan. I followed the assembly instructions about the orientation of the fan on the blue duct. I am surprised by the air flow direction. The fan does not push air through the heatsink. The fan sucks through the heatsink. Hope I am clear... Is thtat "normal" ? Thanks !