Apparently my housemates have told the landlord about the dial and he's going to get on to the suppliers, but who knows how long it'll take. I'm probably going to freeze in the meantime, it's so cold! Heating has been off 3 days now! Where the thermostat dial is attached to the boiler it's not a simple swap a box, and he might not be allowed to do it himself, I'm not sure. Hope it gets fixed soon though!