Cleaning a microwave oven - inside and out
There is not much work that needs to be done in order to maintain a microwave. Regular cleaning can help to prevent potentially expensive repairs in the future, and can even help to prolong the life of your microwave.
The internal cavity should be cleaned after each and every use. Wipe clean with a damp cloth and some detergent. In the event that food deposits have built up and have been caked on to the inside of your microwave, loosen it by placing a cup of water in the microwave. Set the microwave on 'high' for five to ten minutes, allowing steam to disperse within the unit. You may also want to try adding a tablespoon of vinegar or lemon juice to the water to further help loosen the food residue. Food spills that are not properly cleaned up can lead to arching and sparking inside your microwave.
If the internal cavity has any burn spots, sand them smooth and then paint over them with microwave touch up paint. If your microwave has any burn holes in the cavity, call an appliance repair technician and refrain from using the unit. If the wave guide has burn spots on it, replace it along with conducting a thorough cleaning. If you think any food has slipped through the perimeter of the wave guide cover and into either the roof or the walls of the oven cabinet, then remove the waveguide cover and throughly clean the area in behind it as well.
The outside of your microwave should also be regularly cleaned in much the same manner as the inside: with a damp cloth and some detergent. If you use a spray bottle, do not use it near the door latches, ventilation holes, or anywhere else where liquids can seep into the cavity. Also, do not use a dripping wet cloth for cleaning. Use extra caution when cleaning on and around the touchpad and the area surrounding the touchpad. If any liquid makes it way underneath the touchpad, it can lead to unresponsive keys, stuck buttons, or even erratic operation.
Finally, be sure to refrain from utilizing strong solvents. A small amount of isopropyl alcohol can be used to remove sticky residue.