Below is an “average” cleaning job – if there is such a thing: But there is no such thing as a “maintenance free” vacuum system, especially when it comes to the dirty conditions of processing luminous tubing. Manifold systems need periodic cleaning and maintenance. The longer the operator waits the worse it gets. This old PNL Ultra-Vac® Jr. manifold and diffusion pump had been neglected for years and the system was to a point where it could not even do a poor pumping job, much less the quality processing it was intended to. After we performed a 3 step cleaning procedure it was necessary to burn off the remaining residue in the annealing oven. Each component was then rigorously vacuum checked before reassembly. The components now look and, more importantly, function as new again. The owner thinks they have a “new” system!