It's the first time I've used one, I adapted a stew recipe and used most of the liquid advised expecting none to be evaporated. I put it on high, planning to wait 7/8 hours for this 2 1/2 hour recipe to cook as per manual. 4 hours later it had boiled dry (burnt on the side and everything). Basically is the slow cooker defective? You could see the steam rising from the lid and bubbling out from under it but I left it for 4 hours not wanting to disturb it in the first half of cooking. Help!