It's not the central gate, the central one you'll open from behind it, the central one is one of the gates that you just open to make it easy to get back there (you make the whole way around it and then open it so you don't have to make that path again). It's the one gate to your left. See the sand tank with the path in the map? It's just to your left. There is a vane or something just above the gate, open it and pass through the sand to the other side.I still read your hint and I was unable to finish the room. The fans you mentioned are on the other side of the door so I cannot reach it. Here are some pictures I took for visual aid.I am currently in the 3rd dungeon and I got the wind item. The room after it which I think is the main room the only thing I have access to is a bomb but I dont see anything to blow up within the room. What can I do at this point?To the left of the door where you came after getting the gust bellow and the map (you are at the main central room, right?), there is a closed gate with a fan like thingy at the top of it. Blow it to open the gate. Enter it and you'll see that your path is covered by sinking sand. Open your map and you'll see a path under the sand, just like in the desert.
http://i.imgur.com/0EX8E.jpg
http://i.imgur.com/SFlRQ.jpg
No, there's a pressure switch on the other side of the left gate. I'm stuck on that part too.