I have noticed some differences between the 737 6/7 -> 8/900. Maybe somebody can shed light on few things:a) The FMC shows sometimes an A behind the altitude on the leg page. I have never noticed this in the 6/700 version. In the 8/900 it shows something like 5000A. What is the A for?:( When I use RTO (brakes), in the past after the take-off the switch automatically switched back to neutral. In the new version it remains RTO. Bug of feature?c) During the desc phase I get an air cond warning (off shed descent). What do I need to do? I never had this in the past.d) When I switch the center fuel pumps off, I do not get the "low pressure" warnings (lights) anymore (Overhead panel). For all wing pumps it works as it did in the past. Any ideas?

Ms/Mr Any Ideas?Please take a moment to read the forum guidelines and sign your posts with your real name.To your questions.a) A stands for At or Above. It basically means that the FMC will interpret 5000A as a floor altitude for that waypoint. You also have B which stands for At or Below where the altitude works as a ceiling altitude. :( Feature. Changed to represent the real thing.c) You need to set your cabin pressure altitude to the altitude you are going to cruise. THe default value is 35000 feet if you don't reach this altitude and start your descent early you will get this warning. You can reset the cabin pressure altitude alarm by changing it to your current altitude.d) This is the right logic for the fuel pumps. Low pressure warning for centre pumps only when pumps on and low on fuel in tanks.Hope it helps,

Thanks a lot, I really appreciate your help. Sorry for the missing name, hope the signature will be included with this post.