Unscrupulous HVAC Technicians often use the symptoms arising from a bad run capacitor or contactor to sell a trusting homeowner a whole new air conditioner. If you have a quality air conditioner and furnace, and properly maintain it, it should last 25 to 30 years. If in doubt, always get second and third opinions.

We called what we thought was a trusted HVAC company in our area to come out and look at our 8 yo ac/heat pump. He looked at it all of 5 minutes and declared we need a new one.

As I was showing him to the door, he declared we owed him $45 for his "service" call. Ha! A quick chewing on the ear of whoever answered their phone took care of that.

If someone tells you that you need to replace a relatively young opinion--especially when they don't take the time to thoroughly check it out, get a 2nd (or 3rd!) opinion!

There are unscrupulous folk in all facets of the service industry.
Don't get me started! :)