Why isn’t my bedroom radiator heating properly? A Why isn’t my bedroom radiator heating properly? A radiator can’t heat if the air that’s in the radiator can’t be released. If you have a steam system, a new air valve may be required. If you have a hot water system, air may need to be purged from the bleed valve.Leave a Reply Cancel replyYour email address will not be published. Required fields are marked *Comment *Name * Email * Website Save my name, email, and website in this browser for the next time I comment.