It is possible to paint vinyl siding, but doing so requires some special techniques for preparing the siding, and only paint that is specially designed for use on vinyl siding must be used. The choice of color will also affect the quality of the paint job, as it's important to never use a color that is darker than the original color.
Painting the siding with a darker color than the original can cause the siding to warp due to it absorbing too much heat. The siding must first be thoroughly washed by hand using soap and water before painting. Siding should never be power washed, as this will cause water to get behind the panels, which will ruin the new paint job.
When choosing paint, it's important to buy a product that contains a mix of acrylic resins and water-based urethane. Most experts recommend buying a high-quality exterior latex paint, preferably one designed for vinyl if possible. Painting should never be done in direct sunlight. Instead, one should only paint siding on an overcast day or when the siding is fully in the shade.
Vinyl siding is designed to expand and contract with heat, so it may be necessary to touch up the paint in cold weather, as the siding will contract and cause unpainted gaps to show between the panels.