GILLIG LOW FLOOR, Руководство по обслуживанию

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Air System
Chapter 6– Air System
The compressed air system operates the service brakes, emergency/parking brakes, suspension system,
passenger door, and the driver’s seat. The windshield wipers and the wheelchair ramp are electrically
operated and require no compressed air.
The basic air system is composed of an air compressor, air governor, air dryer, air reservoir tanks, over-
pressure (relief), and check valves, and the tubing, hoses, and fittings necessary to connect all the com -
ponents.
AIR SySTEM OPERATION
Refer to Figures 6-1 and 6-2. Air is supplied to the air compressor through the engine air cleaner. The air
compressor is gear driven by the engine and provides compressed air to the ping tank where the pulses
from the air compressor are absorbed, providing smoother and quieter operation. The air dryer removes
moisture from the compressed air. Accumulated moisture is regularly expelled from the air dryer onto
the ground beneath the coach and will account for the occasional air discharge heard. The compressed
air fills the air tanks. The air governor senses the air pressure in the wet tank and operates to maintain
pressure between 110 and 130 psi. When the wet tank pressure reaches 130 psi, the air governor turns
off the air compressor by supplying air pressure to the air compressor unloader system. When the wet
tank pressure drops to 110 psi, the air governor turns the air compressor back on.
The air dryer and the wet tank also have a relief valve to prevent overpressure should the air governor
fail. It is set to prevent pressure in excess of 150 psi. The air dryer desiccant cartridge should be checked
at least annually to ensure it remains serviceable. Servicing the desiccant cartridge should be attempted
only by qualified air system mechanics.
Dry air is delivered to the wet tank reservoir, and from there, compressed air is supplied to the other
three air reservoir tanks: the primary (green) tank, the secondary (red) tank, and the accessory tank. The
tanks are unpainted; the color designations refer to the pointer color on the air pressure gauge and the
color of the tubing connecting the elements of the primary and secondary braking systems.
Each reservoir has a check valve at the supply port to maintain pressure in that tank if other reservoirs
or air lines were to leak. Each tank is fitted with a standard manual drain valve and should be drained of
moisture, if any, on a daily basis.
Air from the primary and secondary tanks operates the brakes, and air from the accessory tank operates
the suspension system, the passenger door, and the driver’s seat.