TEST OR INSPECTION
If air lines are under pressure when they are disconnected, they can whip around
and cause injury to personnel. Caution should be exercised when disconnecting
air line fittings.
Air lines may be under pressure when control valve is operated. If under pressure
and air lines are disconnected, air lines may whip around and cause injury to
personnel. Caution should be exercised when operating control valve with air lines
Air pressure is checked by disconnecting air lines at ground sweeps valve and observing
air pressure escaping from air lines, when ground sweeps control valve is activated. Air
will escape from blue air line when GROUND SWEEPS switch is put to on position, and
escape from red air line when GROUND SWEEPS switch is put to off position. System air
pressure may drop below 85 psi (586 kPa) during this procedure.
Put GROUND SWEEPS switch to off position (WP 0004). Put FOAM SYSTEM switch
to off position (WP 0004). Disconnect air lines at ground sweeps nozzles valve. While
an assistant puts GROUND SWEEPS switch to on position (WP 0004), check if air
pressure is present at ground sweeps valve.
If air pressure is present, replace ground sweeps valve (WP 0576).