The best and easiest way to clean oven racks is to first lay some old newspapers inside of a trash bag. Next lay the oven racks on the papers then spray liberally with oven cleaner. I do this outside of my home. Then let them stay for several hours or overnight. Finally, rinse the racks with a water hose, dry them, and put them back into oven.
By Patricia Hamm from Lexington, NC
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Get yourself a can of Easy Off for Cold oven cleaning. Have a couple of big 55 gallon trash bags and a stack of old newspapers. This will work on oven racks and grill racks, too.
Lay a barbecue grill rack on the lawn overnight--the dew will combine with the enzymes in the grass to loosen any burned-on grease. Try it with messy oven racks, too.
Placing dirty oven racks in a plastic trash bag with some household ammonia is an effective method for cleaning them. This is a page about using ammonia for cleaning oven racks.