Shelly, on your 1588 open it up, and look at the top part of it, you'll see a yellow box to the right of the fan. Now look in that box, and you'll see little switches. One of those switches will be pushed in a direction opposite the others. To adjust, if your's is high, push the one that is different back the other way so they're all the same, then push the one to the left of that one up. That will lower the degree by one half degree. Each switch represents one half degree, with the switch nearest the fan being the lowest setting....