Are you cleaning or replacing your return air filter every 30 - 45 days? If not you should be.
Diamond Heating and Air recommends that you change your filter or clean it every 30-45 days when the system is in use. This provides cleaner air in your home. This saves you money on your utility bills and extends the life of your HVAC System. If you are using your AC or Furnace you are using your return air filter. All the air must pass through the filter before getting conditioned.