I was up on the roof today to put one of those Cyclone vents on top of the existing vent.
My first clue should have been that the top of this round vent looked unlike the others I've had, it has a shiny almost mirror finish. Anyways I cut away some of the dicor and removed the 3 screws.
When I lifted it off I found no pipe but instead a grey telephone wire coming from within the coach up to the underside of the top of this vent where it plugged into a conventional telephone jack.
Ok.....What the heck is it?
Ron