This pic shows a stack of copper tubes, each of which is about the diameter of a pencil. These tubes are a miniature version of copper plumbing pipe work except that they carry air instead of water or other liquids. These were once part of a pneumatically-controlled climate control and fire damper system. Instead of wires to transmit information, these slender copper tubes were used to connect thermostats, dampers, heaters and air conditioners which all operated on pressure differentials in the system.

The tubes run all over older schools, offices, hospitals-- anywhere a large heating and cooling system were used.

There were workers who installed this "HVAC copper" to all the many parts of a building, interconnecting them using these tiny pipes. There was an art to shaping the copper into the bends needed as the complexity could become quite impressive. Those who did such work were sometimes called "spaghetti benders" and employed small tools, torches, cutters and fittings to get the job done.

This pile of copper is headed for the scrap buyer, its usefulness having passed when it was obsoleted by modern digital and wireless controls that didn't require wasting so much material.