Is cool air not coming though the vents, even though you’ve set it to cool? Do you have some rooms that cool slower than others—or not at all? Have your electric bills gone up, or are you seeing water spots on your walls and ceilings?

These are signs that your air conditioner isn’t functioning properly, and you need help right away. But instead of waiting for something to go wrong, having it checked can make a big difference in your repair bills, or avoiding one altogether.