I never deflate mine. Also, I would NEVER, NEVER leave it powered up. If it has an on/off switch leave it plugged in but turned off. A good friend left the compressor in the on position allowing it to turn off and on automatically at night. It caused his shop to burn down. If the compressor is in good condition and does not leak air that would not happen as there would be no need to recycle. But I don't take chances.