The man who came to service my air conditioner was...

The man who came to service my air conditioner was very nice, and seem to really know what he was doing. My only complaint was that the company is now trying to get all customers to add another part to the air conditioner that is only a few years old. If it was so necessary why wasn't it put on right away when I purchase it? Just frustrating that I pay this plan so I don't have to come up with a chunk of money each time.