#ad It’s something we never think about except when our refrigerators start getting sluggish and running warm. The coils underneath the appliance. Ideally we should vacuum the dust off them twice a year (more if you have furry pets). They may be covered by a panel in the front or back of the unit. Unplug your appliance. Remove the panel, and gently scrape across and between the coils with a long-handled appliance brush. Follow with the crevice attachment on your vacuum cleaner. In special appliances, you may need to check the manual  to see if it requires professional cleaning.