Originally Posted by hadagutfull
Not sure what the regs say but I would be surprised if an aircraft so equipped could operate without a serviceable APU.
The B717 MEL that I operate to allows for no APU for 10days, with certain provisos. Air cart/bottles plus ground power required at each port.
Hot refuelling is only permitted under strict conditions, to get one to a maintenance base, should the APU fall over at an out-port.
As an aside, i've run an engine for air-con during boarding with no issues from the aerodrome operator.