Depending on if you are in an IBC/IFC community, the IBC/IFC has language addressing reuse of materials and equipment. 2009 IFC Section 104.7.1. Now being it is a fitting, I don't think there would be much resistance from this section. But just throwing it out there.
If it helps at all, I have also heard numerous individuals refer to the air compressor as the "jockey pump" on a dry system. Other than that or if the system has a pump on the supply side, I can't think of a reason why there would be one.
