am i wrong for thinking our utility split should be based on who uses what

the bills are split three ways right now and i keep feeling like two of us are covering more than our share. one roommate runs the ac nonstop and takes hour long showers while the rest of us try to keep things reasonable. i suggested we track usage or at least adjust the split so the heaviest users pay a bit more, but the idea got shut down fast. now i am getting sighs and comments about how we agreed to split evenly from the start. honestly i do not want conflict over a few dollars, yet it feels unfair to keep paying for someone else's habits without any adjustment. i just want a system that feels balanced instead of automatically equal. is it wrong to ask for that conversation or should i just keep quiet and accept the current setup?