The anti-botting tools used I believe are a lot more intelligent than they used to be and I believe they generally look for refreshing at super-human rates (which usually indicates the use of a program/script/function rather than a person)... however, refreshing too quickly in a short amount of time by hand could start triggering the "Slowdown Hotshot" messages (if those are still around). If you receive one of the messages that state you are refreshing too quickly, that's when you need to slow down before triggering something you don't mean to. Getting one slowdown hotshot message shouldn't bring on a ban flag or anything as they happen sometimes innocently, but you should take it as your unofficial warning sign if you get there.
PS - Remember to not use any automated means of refreshing. If you aren't doing it by hand, you actually are botting.