Receive exclusive offers before anyone else! We won't charge you for the carbon monoxide detector (rrp £). This is an ideal solution where you have the available floor to ceiling height ... Is it recommended to ask for references from a plumber? We have a number of drain cameras, or cctv cameras as they are known in the industry, which can be placed down your drain pipe to see what is causing your blocked drains. Registered name: db heating limited trading office address: unit , west devon.