I teach science after hours to high school students that need extra help with the subject, but I operate out of my home and do this every other night a week, and one of the things that I always make sure is in place is that the room that I teach in has the best and most comfortable temperature control so that I feel much more relaxed and so the kids that I am helping can concentrate more.
I always make sure that I have both a portable air conditioning and a portable space heating system on hand in the event that the central heating and a/c were to break down while I was teaching a science lesson! That way, I would not have to cancel the class and the kids can get the most out of their extra help that they need with me teaching this subject after hours during the week.
The central heating and a/c works great in that room normally, one time when I had an unexpected heating and a/c breakdown, I had to cancel my science class for the day and the kids that were supposed to come were behind in their studies! Ever since that day I came up with the plan to make sure and have a portable air conditioning on hand and a portable space heater, so if it ever goes out again these days, I can still do my classes as usual. It is a great method and it is safe and it works well.