As a former bus driver I can tell you a couple of things abut the a/cs on the busses.
1. The temp is preset at maintanance and there is nothing I repeat nothing that the driver can do about it. Around the spring and fall, at certain times of the night, the a/c will turn off, as it is too cool for the a/c but not cold enough for the heat. Its real fun when it rains since the a/c also pulls the humidity from the guests on board out. But wont when the a/c cuts out automatically.The windows fog up real quick.Been there done that one too many times.
2. Depending on what bus type you are on, the newer busses may seem colder than the older busses. It has to do with the way that the air is blown into the bus. On the older style busses, the ones you have to step up 3 steps on,up to bus number 4814, the cold air is blown thru the interior of the bus thru a channel towards the center of the bus. The window vents, are not as good as they were when the bus was delivered. Generally the closer you sit to the front on these busses, the warmer it is.The newer busses, 4815 and up, the ones that look like boxes on wheels and sit really low to the ground, the ac vents are pointed at the windows and blow down across the windows.
In the newer busses there really is nothing you can do about the cold feeling, in the older busses, sit in one of the aisle seats, or nearer the front of the bus. Sitting on the back seat has a disadvatage. The a/c intake is in the center of the bus, over the rear seats so youll have the incoming air blowing past you.