With the size of that place, I doubt they had anything more that just fans blowing outside air in. Unless it was overly freezing or sweltering. It is one way for the hotels and convention halls to save cash.
You can see me with a couple friends (who were 1960s Batgirl and Robin) dancing like fools about 0:11. Also got to meet @RandomAdam in person, which was awesome.
If you see me (I'll be Red Hood again today) just shout "Vox" and come and introduce yourself! I'd love to meet more RPF members in the flesh!