We just started servicing a building that has two large VAV package units and a hot water boiler with pump all located on the roof, this system is very common for the area. Downstairs in the suite it has your typical VAV boxes with pneumatic thermostat, damper actuator, velocity controller and HW reheat valve. Here is the part I've never seen, all the hot water reheat coils are located in the high side duct work about two feet before the inlet of each VAV box. One of the problems we are having is the box is never seeing the 1" WC it requires for the velocity controller to operate because the air hits the hot water coil first causing a pressure drop, the velocity controller always keeps the damper open because its seeing low static at the pitot tube ports. If it was one or two zones I would just think someone screwed up but every perimeter zone is this and it looks original from possibly late 70's early 80's. Its a 150 ton system so there are alot of zones. What were finding is the isolation valves to most of the reheat coils have been closed over the years. Has anyone ever come across a system like this and if so did it work ?