It is important for furnace inspections every year. The main reason is for you and your families safety.
An inspection involves at least 14 checks.
They check your gas pressure, temperature rise, clean flame sensor, check amp draws on the motors and igniters. The most important is they check for carbon monoxide. This is an odorless gas that can leak out of the furnace heat exchanger when heating. If it is left unrepaired the gas could make you sick or even kill you.
It is also important to change your furnace filter monthly.(one inch). Four or five inch filters need to be changed every 6 months . Even if you have air conditioning.
Make sure to keep combustibles ,such as paint, away from the furnace . Code requirements recommend thirty inches of clearance in front of the furnace and water heater .
Keeping you furnace running efficient is important and getting your car serviced.