My furnace runs for about an hour then shuts off before the thermostat is satisfied, however the combustion fan remains on, I can not shut it off from the thermostat I have to shut it off from the main switch. When I turned it back on it goes through every cicle however when the blowers cycle comes up it will not come on the burners turn off and the house smells like burn paper and the combustion fan remains on.

Open all registers

Make sure air filter is clean or new and that the return air is not blocked.

If the blower will not come on and it smells it is a possibility the blower motor is defective.