I’ve just bought (used) a Lexmark 4039 plus10 which came with a spare toner set. The cartridge is running out of toner but I can’t figure out how to split the toner part from the cartridge. I know it must be obvious but it has beaten a computer novice like me. Can anyone help please? Thanks.
upgrading control system on oil central heating. new control pack comes with 3 port valve. can i just change the control part of the valve without replacing the pipework or does the whole unit have to be changed. :?