I have spent alot of time sitting on taxiways in kennedy, with the door closed thank you very much! The APU is a MEL'able item and not very strong arguement for refusing airplane, regardless of how hot it is outside. There is a more diplomatic solution to the problem. You accept the airplane ask for extra gas (since you will have to run a motor the entire time) and you go out and taxi. If you just so happen to go below min T/O becuase your delay was too long.... OH WELL!!!!! You will then return to the gate, hopefully sometime the same day

Beagle