Abstract: A quick color change powder coating system has a powder supply, a powder pump that receives powder from the powder supply through a suction pick-up tube, a spray gun and a powder hose that connects the pump to the gun. The apparatus includes a purge air switch assembly and a first air source that provides air at purge pressure to a first inlet of the purge air switch assembly. A second air source provides flow rate air to a first pump inlet and atomizing air to a second inlet of the pump via a purge air switch assembly. Powder is drawn up the tube and into the pump by suction produced by flow rate air into the pump. A purge inlet is associated with the powder inlet to the pump. The purge air switch assembly operates in response to a purge control signal to connect purge air to the atomizing inlet at the pump and to the pump's purge inlet; whereby the pump, hose and gun can be purged at the same time.