Checked customer complaint about a banging sound from his water pipes. The customer had recently had a new well pump and pressure tank installed for his home and had started to hear a banging noise when he would flush the toilets and there was air in the pipes when he would use a faucet or shower. Presented customer pricing to perform a diagnostic to make sure that his pressure tank was not damaged. After pricing was approved I drained the pressure tank of water and checked the air pressure in the top. The air pressure was at about 38psi. This meant that the bladder in the tank was not ruptured. I filled the pressure tank back up and bled the air from the lines. I had the customer turn the well pump off and I flushed the toilets to see if there was any air. There was no air on he lines when the pump was off but when the pump was on there would be air in the lines. The customer decided hat he would call the well company that installed it to make sure his well pump is not pumping in air.