I`ll try to keep this short. I started my furnace, everything was OK. When it was time for the blower to kick on it did not. I opened the bottom door to check the blower to see if it was tied up, it was OK. I put the door back on and it took off. When it was done, the blower kept running. It will not shut off. Any help?

This may or may not help-there may be a switch you hit.Blower,Off-Automatic and Run-Mine is marked summer.