We install 2 fans in differents rooms, after a few

There is a small opening on the top of the fan with four small (DIP style) switches. In order for the remote to work, both the fan and remote must have the same combination in the switches. Remove the battery cover from the remote to have access to the switches, then using a small tool (a ball point pen will work just fine) set the switches to the same combination both in the remote and the fan. For example: If you set the remote to: off, off, on, on; then the fan should also be: off, off, on, on. You can set the remote for the other room with a different combination as to avoid any interference between the two. Please rate this solution if it was helpful. Good luck and thanks for using Fixya!