Are there any reasons why changing the alternator in a vehicle would cause the air conditiner to ....?

start blowing air that is not very cold?|||other answers so far are possible, also possible that in process of changing the alternator, some wires were not properly hooked back up. such as a/c clutch wires or the fan wires. try starting the vehicle with a/c on and see if the clutch on the front is rotating. this will tell you if the compressor is pumping or not. if not then a leak was possible or the wire to the clutch may not have been properly hooked back up|||Yes. Someone hit one of the hoses and caused a small leak while changing the alternator, or the belt was not tightened up after instalation. Have the latter checked first.|||it is possible that an a/c line was disturbed enough to cause a leak... some models may need to be reset after the battery cable was removed