How to properly care for a gas furnace:

Clean or replace the filter quarterly

Ensure the blower motor is functioning correctly 

Set the thermostat to 68 or lower

Ensure the exhaust flue to the outside is clear of debris

Remove all flammable objects from around the furnace

 

How to properly care for an HVAC unit

Clear a two-foot space around outdoor AC unit

Buy a high efficiency pleated air filter

Keep the AC unit free of dirt, grass, leaves and other debris

Replace the air filter every month during the summer and every six weeks when you are using heat