Inspecting Microwaves on a Home Inspection
Microwaves, similar to other appliances in the kitchen, are not required to be inspected according to most standards. However, being comprehensive will help satisfy customers and provide greater peace of mind.
If the fridge had an ice/water in the door I would typically take that water I filled my coffee cup (carry a cup in your tool bag) with and place it in the microwave oven. Now any modern microwave oven should be able to heat to a very high temperature or boil a cup of water in about a minute. That being the case I set the microwave for 1 minute on the highest setting. While the water is being heated I check the rotisserie function (spinning plate) and the exhaust fan operation. After one minute the water should be boiling or very hot when you test it. If it is lukewarm, then I would say the magnetron (the thing that generates the microwaves) was bad and recommend repair/replacement.
The exhaust fan on a lot of microwaves is improperly vented. Many have the motor assembly turned (it can be rotated for either type operation) so the air is directed upward as if it were being sent into a duct or vent to the exterior. They should typically be turned so they vent back into the room (recirculate) through the metal and/or charcoal filter. If you were to feel for airflow between the top edge of the microwave and the cabinet above you would feel air blowing out from between them. This is wrong and should be fixed. Those filters should be cleaned periodically in the dishwasher to remove the built-up grease.
Back to Home Inspection Industry News >>