Blower fan will not shut off; where is the limit switch located at on a concord furnace?

I may be the fan thermostat itself or a fan relay or even the room thermostat. And possibly there is a good reason it continues to run longer than you expect. I would hesitate to tell you to adjust a limit switch before checking everything else. If you don't know how to do that troubleshooting first, I would encourage you to call a repairman.

EPM