An aerosol spray can too clogged to work is often frustrating, because it has failed in your moment of need. It is even more frustrating when the can's contents are still plentiful. However, you still have recourse. You can unplug it with some common household products and a little time.
Find a well-ventilated area. Pull the plugged sprayer top off the can. Place the top in a small jar that has a lid.
Pour just enough paint thinner or white spirit into the jar to cover the sprayer top. Tightly seal the lid. Set the jar in a safe place away from children and pets. Allow the top to soak overnight.
Put on a pair of rubber gloves. Remove the sprayer top from the jar. Seal the jar and set it aside for other uses. Wipe the top clean with a paper towel.
Hold the top between your thumb and forefinger so you can access it from the bottom. Insert a needle or a thin wire carefully into the tube. Gently wiggle the needle or wire to clear away any remaining clog.
Insert the extension tube from a can of aerosol lubricant. Slide the sprayer top onto the end of the tube and hold it in place. Spray the lubricant in small shots into the top until it is unclogged.
Paint thinner and white spirit are flammable. Keep both away from open flames. Follow the warnings on the containers. Be careful not to distort the shape of the tube in the bottom of the sprayer top when you clean it out with a needle or wire. If you do, the nozzle won't work properly.