I have a furnace that is about 14 years old, and a central air conditioning unit that is about seven years old. I noticed yesterday that, although the house was cool, the fan was not blowing. It will not blow when either the heat or the AC is on. I turned everything off. Please advise as to possible problems so I will be semi-informed when I call the heating and cooling company. Is there anything I can/should look for myself?
Thank you,
Mary

The fan is controlled by a relay, maybe even different ones for heating and cooling. You furnace may be new enough that the relay is on a control board, making trouble shooting more difficult. There are also limit switches and timers that start the fan after the heat is on and keep it going after the furnace or A/C go off. All of these can go bad in addition to the blower motor. If they decide to replace the control board, the labor shouldn't be too much, but the parts will curl your teeth.