Why is my Air Compressor pulsing at low PSI settings? When filling low pressure objects, such as sports balls, to a PSI lower than average atmospheric pressure (~14 PSI), the air compressor may pulse on and off during inflation. The pulsing is due to the compressor creating air pressure stability within the object to achieve accurate inflation pressure, and the machine will turn off automatically at the set pressure per normal. Related articles What is the maximum pressure? How long will the battery stay charged if not used? Does the 24V-1500FL-LTE-P1 unit come with a battery and charger? Why does my air compressor not shut off right away when it reached the set pressure? How do I correctly operate my Portable Vacuum Cleaner?