My Carrier furnace is not starting for the first time this fall. The Diagnostic lights indicate pressure switch open because of reduced flow. Is there a re-set switch or some way to diagnose this problem. Is it possible there is something blocking flow? What can I do with this? In researching this, it also seems that my inducer blower is not coming on. Might that be the problem.

This indicates a lack of air flow up the vent, check the vent for obstructions, check to insure the induced draft motor is operating, check the tubing from the induced draft blower to the vent is in order and not cracked or broken, Good luck, Mike