A fire protection sprinkler system and method of inerting a fire protection sprinkler system includes connecting an inerting system to the piping network of a fire protection sprinkler system having a piping network and at least one sprinkler head connected with the piping network. The inerting system includes an inert gas source that is adapted to supply inert gas to the piping network and an inerting gas vent assembly. The gas vent assembly has a gas vent adapted to discharge gas, a solenoid and a control. The solenoid is adapted to selectively open the gas vent and to close the gas vent. The gas vent discharges gas when the solenoid opens the gas vent and does not discharge gas when the solenoid closes the gas vent. The control is adapted to operate the solenoid in a manner that allows the gas vent to discharge gas for a limited amount of time.