Many household ovens can be cleaned by turning on your oven's self-cleaning function. This cleaning method will not do much for the trays that are in your oven. Burnt food, grease and other grime can accumulate on the oven trays. When left untreated, these substances can be more and more difficult to clean off the oven trays.
Place bath towels or cloths along the bottom and sides of your bathtub. Doing so will prevent scratches and stains from appearing on the bathtub.
Put the oven trays on top of the towels in your bathtub.
Fill the bathtub with hot (not warm) water. Fill the tub only to about 80 per cent capacity in order to prevent the tub from overflowing.
Pour approximately one-half cup of ammonia into the bathtub. You don't need to stir the ammonia into the water.
Leave the oven trays in the hot water and ammonia mixture for roughly 15 to 30 minutes.
Remove the oven trays from the liquid and drain the tub. Once the tub has fully drained, you can set the trays back on the wet towels inside the tub.
Rinse the oven trays thoroughly. Drain the tub of any remaining liquid.
Pour one tbsp of liquid dish soap onto a wet sponge.
Scrub the oven trays with the wet sponge in order to remove any leftover grease or food particles from the trays. Rinse the trays in your bathtub. You can then leave the trays in the bathtub so that they air dry, or wipe the trays dry with towels or cloths.
Due to the smell of the ammonia, open the windows in your bathroom and your home in order to remove the smell from your home.