When all of us first moved into our house, I hired a professional Heating, Ventilation & A/C contractor to inspect & maintenance the oil furnace & a/c, and he assured myself and others that the plan was in nice working order & should last quite a few more yearsâ€¦ Although he advocated that I enroll into a maintenance plan, I declined. I didn’t want to make the commitment to something that I felt wasn’t truly necessary. As long as the heating & cooling plan continued to beginning up & supply comfort, I did nothing beyond the occasional filter upgradementâ€¦ Last summer, our whole family suffered from frequent headaches, but my kids complained of sore throats, congestion & itchy eyes. My partner was consistently coughing & sneezing. I wasn’t sure what was causing it. I never suspected the a/c. The only reason I called for a/c maintenance was because the machine eventually quit altogether. The Heating, Ventilation & A/C contractor I hired took the cooling machine apart & showed myself and others the buildup of grime inside. There was an alarming amount of mold growing on the evaporator coils. There was algae thriving in the condensate drain & a great deal of dust, lint & assorted contaminants coating every component. The contractor told myself and others that every time the cooling plan started up, those harmful toxins were becoming airborne & getting introduced into our breathing air. Plus, the buildup was restricting airflow through the system, causing it to work difficult & resulting in higher energy bills! Fortunately, a thorough cleaning fixed all of these problems. I have now invested into a maintenance plan that includes respected maintenance of the oil furnace in the fall & the a/c in the Springtime.