Came out to call for a system not heating properly. Customer stated that the system sounds like it is operating, but no heat is being felt. I checked the system over and found a couple of issues. The pressure switch wasn’t closing properly due to blocked inducer port. Thais was causing the inducer to run constantly on and off, without being able to complete the heating sequence. The blower capacitor was also weak and could fail soon. Made customer aware of both issues. Customer had me replace the capacitor and I also cleared out the inducer port. Cleaned flame sensor and dust out of the burner cabinet. Cycled heat on and checked amps, temperatures and gas pressure. System is now heating properly. Advised customer that the system is original to the home and may want to start planning for replacement. They moved in recently and have a home warranty