I move some comments made by @TomWijsman and me to a chat room and since we stop to talk I think will be good to delete that room.
How can I delete a chat room I opened?
Deleting chat rooms is possible, but only for moderators. In cases were you feel strongly, ask a moderator do delete it; however for cases where you just think "this doesn't matter anymore", just leave it be. There's still the issue of community moderation; if people abuse the chat in any way, but are quick enough to delete their room, nobody will ever know. All chat activity is intentionally public (except for behind-the-scense moderator chats of course).
And inactive rooms will be removed after a while anyway (either frozen or deleted; see the corresponding FAQ entry for the precise rules).