Comment 1 for bug 1252091

You'll find that it works as expected in gvim. the reason is that <c-h> is the default escape sequence for backspace in old terminals and therefore terminal emulators do exactly that. Some emulators can be told to pass this control sequences on, but most can't.

Sorry, either use gvim or switch your terminal emulator (no idea which one can be used in linux though, on mac iterm2 should be able to do this).