Neil Williams wrote:

Was it actually aircon, or just the giant fans in the back that just
suck air out (and so in through the windows)?

It's got 3 big fansa at the back and a unit above the stairs. Between
the 2, along the right hand ceiling of the top deck (where the adverts
usually are) is a line of slots from which comes the cold air.

There was actually cold air coming from them yesterday, the water
stopped pouring out of th stair unit once a few of the windows were
closed. The driver mentioned a malfunctioning air conditioning unit on
the PA system