A:Answer It is a slow cooker, so It takes a while to heat food from refrigerator cold - I usually heat food in the microwave first for use at parties. Also, be sure to have enough liquid-sauce or gravy, broth etc, to keep the food moist - and that also improves heat retention. The cooker will stay on as long as you have it plugged in and turned on - but if there isn’t enough liquid, the top will get cold and dry out while the bottom burns. This is not a flaw in the appliance, it is basic physics. Keep food moist and make sure to stir it occasionally and you’ll have delicious party food.