Yes, normally on the ground with OAT above about zero, air is drawn in from outside, and then exhausted overboard with two fans and two valves. If any of these fail, then air is drawn from the air conditioning system, downstream of the pack valves. ( The air upstream of the pack valves is too hot!)
This means that there are limits for how long you can have the aircraft powered with a AEVC failure with no packs running.