Looks to have an easily accessible exterior capacitor (the black bump that is just behind the red sticker). If the circuit breaker doesnt trip, you can probably just replace the capacitor and be good. The capicitor adds extra current at start-up to get the motor spinning. Often when they go bad motor just sits there and hums. You need to have system deenergized and discharge any residual voltage in the capacitor to avoid any shock. Once you have the info printed on the side of the capacitor, you can find replacements online for ~$8. If you aren't comfortable or knowledgable around electricity, find someone who is to do it for you.
I keep a spare on the shelf as Ive replaced a couple in mine over the years.