Air can get into household water supply pipelines if construction is carried out on the lines or if the water has been turned off and the pipes drained. The air formulates into pockets that causes hissing and spurting as it leaves the faucet, and even creates a knocking/hammering sound as it is forced against pipe joints. The force of the air against the joints is potentially harmful, endangering the pipeline's structural integrity. Removing air from the pipes is a simple procedure, usually taking less than an hour to complete.
Turn off the water supply at the home's main shutoff valve, located on the incoming water line which is usually in the basement.
Open all faucets on the property halfway, and wait for the pipes to fully drain. Also flush all toilets to remove as much water from their bowls and tanks as possible.
Turn on the water at the shutoff valve. Go to the lowest faucet on the property and wait for all hissing and spurting to cease as air is pushed out of the faucet, finally creating a full flow of water from the faucet.
Turn the faucet off, and go to the next highest faucet on the property. Wait as before for hissing and spurting to stop, and turn off the faucet. Continue in like fashion until air has been forced from the entire pipeline system and all faucets have been turned off.