and I sleep with windows open even when it is subzero outside)
Your doctor should frown at this, mine did when I said something similar. It is, I was told, very unhealthy to breath very cold, sub zero air into ones lungs, can lead to serious problems later.
I found that the CC set the temp according to what they thought was normal, as they were all delightful young ladies from Singapore anything under about 28C was considered 'too cold'!