[EricH]

If your software guys use the stock code, only changing exactly where the compressor and switch are reading, and it fails and nothing else does, then I will be greatly surprised. And I do mean greatly surprised, as there is code that says, "Turn the compressor on" and "Turn the compressor off" and does nothing else.

I can think of a number of hardware failures that would leave the compressor running all match:
--tubing comes out
--major leak in tubing or part
--somebody forgets to close the drain valve
--the relief valve is improperly calibrated, resulting in a leak there
--the regulator is on wrong, causing a vent at 60 psi.