A refrigerator is made of metal and plastic, so you approach painting one the same way you would approach painting an automobile. You need to deal with rust by patching holes and treating the rust to prevent its return. You'll be able to do the best job if you have spray equipment, but if not, you can get good results with aerosol cans. You can even use a brush and roller -- a special technique assures the best results.
Preparation is the most critical part of the painting process -- painters like to say that it's 90 percent of the process, and in the case of painting a refrigerator, it may be 95 percent. Once the preparation is complete, the refrigerator should be clean, rust-free and properly masked, and the existing finish should be lightly etched to better bond with the new paint.
Unplug the refrigerator and move it into the middle of the kitchen or -- better yet -- move it into a work room or outside. Cover the floor under the appliance with newspaper.
Remove the handles and any other removable trim. Each handle is usually held by a pair of Phillips screws -- you may have to unsnap some trim to get to the screws.
Wash the entire appliance with a solution consisting of 1/2 cup of trisodium phosphate per gallon of warm water. TSP is a strong detergent that will remove grease and other kitchen deposits while etching the existing finish. Wear rubber gloves and goggles while using it.
Sand rusty areas with 120-grit wet/dry sandpaper, removing as much rust as possible. Spray the areas with rust-inhibiting primer to prevent rust from coming back.
Fill holes with auto body filler, using a plastic putty knife. Allow the filler to set, then sand it flat with a palm sander and 120-grit sandpaper.
Cover any parts of the refrigerator you don't want to paint with painter's tape. Because it's critical to avoid getting paint on the faces of the door gaskets, you should cover these with tape, bringing the edge of the tape flush with the outside of the gasket. This allows you to paint the part of the gasket you can see.
Set any removable grilles or trim pieces on a flat surface nearby so you can paint them separately.
Whether you spray or brush and roll, you should use a high-quality appliance paint or appliance epoxy coating. To prevent premature failure on plastic surfaces, prime the plastic with water-based primer. Bare metal should be primed with rust-inhibiting metal primer. If you aren't sure whether a piece is plastic or metal, a magnet will quickly tell you. The magnet will stick only to metal surfaces.
Apply primer to plastic and metal surfaces by spraying or brushing. If you brush, make long parallel strokes, using a 4-inch foam brush. If you're using a spray can, hold the can 4 to 6 inches away from the surface, or the distance specified by the manufacturer, and spray with long, even strokes.
Paint the top of the refrigerator first, then the sides and, finally, the front. If you apply the paint with a brush and roller, apply the paint to an entire panel, using a roller, then stroke over the paint with a loaded brush to remove streaks and roller marks. Stroke from top to bottom, starting at the bottom and moving up.
When using a spray can, the strategy is the same, except you're making long vertical strokes with the spray pattern instead of a brush.
Wait the recommended time for the paint to dry -- usually an hour or two -- then scuff lightly with 320-grit wet/dry sandpaper. If you see any drip marks, sand them flat, lubricating the sandpaper with a little water, if necessary. The scuffing procedure is important whether you spray or brush and roll.
Apply a second coat. If you're using a brush and roller, roll first, then brush out the roller marks, this time moving the brush in the opposite direction.
Let the paint cure for at least 24 hours before removing masking tape and reassembling the parts.