Belt Squealing on I30

[mmike87]

When I had my alternator replaced about a month and a half ago I also had new belts put on. Now, when the car initially starts, I get a loud squealing until I rev the engine a few times or let it idle for a minute or so. Then it goes away for the rest of the drive.

I was thinking that perhaps the new belts stretched a little and perhaps I need to add a little tension.

I see the tensioner - but can someone explain how it works and how I adjust it?

Thanks.