i do that. even with the heat on, my bathroom is colder than i'd like it to be during the winter. if i just hop in the shower and take 5 or so minutes, it can still feel cold once i'm done. so i let it run fairly hot, maybe 2 or 3 minutes with the bathroom door closed, then cool it down to where i like it and get in. then when i'm done, i'm not freezing getting out of the shower.