Nothing -- if he wins in small claims court. And it only costs about $20 to file. Yes, you'll need his address, but that's it.
Filing in small claims court is really easy too. Just go down, fill out a sheet of paper, and get a court date. If he doesn't show, you win. If he does, the judge hears the case (think "People's Court" - very similar) and makes a decision (usually not that day - you hear the result in the mail).
I'd send an email and see what happens. Getting a statement from the installer who said it was fried is a great idea too, in case it goes to court so you can give that to the judge.
I've been to small claims court once (landlord didn't return a security deposit -- I've posted the story here before) -- it's actually kinda fun when you know that you're 100% right.