Recorded: Feb 18 2016 @ Siegen Ed.Sprenger hydraulic elevator, 7 floors, installed in 1978 by Ed.Sprenger, renewed 2014 by Heinzerling, capacity 1000 kg.
Roped Hydraulic? I did not see the cylinder or piston with in the shaft, only the hoist ropes. and the guide rails. Also the 1st I have seen a submersible power unit with an external valve. Sounds like compressed air is lifting the elevator cab, and this hissing noise when the cab descends. No rushing noise as I'd expect when the hydro fluid fills back in the tank.
