I am having a few dramas with the new contractor for DE. No change there then. However it is not MHS this time it is Interserve. Basically I am not convinced that my gas boiler is working as it should.... yellow falme burns ocasionally. So a little worried about carbon monoxide. My quarter does not have one fitted and I am not in a position where one is easily obtainable from the shops. As a landlord are DE or Interserve obliged to provide one as they do with fire alarms and the likes? Any references would be appreciated.