How to clean a microwave with no chemicals

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How to Clean a Microwave – wikiHow

• Fill a microwave safe glass or bowl half way with water with a tablespoon of white vinegar and place inside the microwave. Turn on for 5 minutes. The idea here is to steam up the walls of the microwave and loosen the dried-on gunk.
• When it is done, remove the glass container and wipe down the inside of microwave with a clean towel or paper towel.
• The loose gunk should come off easily now, and without chemical cleaners inside the microwave.
• Take out the glass tray or turntable and wash it like a dish. You could even run it through the dishwasher if you have the time.