The EC switch is the econo switch for switching the aircon off - has nothing to due with low aircon gas. If your fan/blower rotary switch is in the O "off" position then the aircon will be switched off, as well the air flap will also be in the closed position. The funny noises you hear will be the air flaps modules working, maybe they are leaking also. Iam not sure why the vacuum pumpwold be running, possibly a leak there also.
regards