BC Transit – Air Brake Course

Dual Circuit
Foot Valve
The Simple Dual Circuit System
In this diagram, the blue lines indicate “supply air”, the red lines
indicate “secondary” or front brake air and the green lines indicate
“primary” or rear brake air. A dual circuit foot valve has been
installed. This foot valve works in exactly the same way as a single
circuit foot valve. However, the dual circuit foot valve is split
internally into two parts. The upper part delivers application air to
the front brakes, while the lower part delivers application air to the
rear brakes.
Compressor
Secondary
Reservoir
Supply
Reservoir
Primary
Reservoir
Left click to begin animation
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