01-12-2016, 12:53 PM
Steve: great diagram and description.
To add some additional, and hopefully useful, information based upon my 93 coach:
The device in the upper right with 2 wires, on my coach that is the switch that turns the "low air pressure" light on-off on the dash. The square just next to the switch would be the pressure protection valve that shuts off the flow of air to the non-brake uses whenever the pressure in the supply tank falls below 65psi.
The reason the the brake tanks pressurize whether the "blue" or "red" valves are open or closed is because the flow of air between the supply tank and the brake tanks runs separately and in parallel to the flows shown on the diagram.
This explains why the brake tank pressures rise from zero gradually and the supply tank gauge will rise suddenly to the brake tank pressure at about the same time the dash "low air pressure" light goes out. It isn't exactly the same time, but in the ballpark.
To add some additional, and hopefully useful, information based upon my 93 coach:
The device in the upper right with 2 wires, on my coach that is the switch that turns the "low air pressure" light on-off on the dash. The square just next to the switch would be the pressure protection valve that shuts off the flow of air to the non-brake uses whenever the pressure in the supply tank falls below 65psi.
The reason the the brake tanks pressurize whether the "blue" or "red" valves are open or closed is because the flow of air between the supply tank and the brake tanks runs separately and in parallel to the flows shown on the diagram.
This explains why the brake tank pressures rise from zero gradually and the supply tank gauge will rise suddenly to the brake tank pressure at about the same time the dash "low air pressure" light goes out. It isn't exactly the same time, but in the ballpark.
Jon Kabbe
1993 coach 337 with Civic towed