Stoves can be easily self-installed but you need building control approval (which is easily done). You may wish to have your stove installed by an APHC or Hetas registered installer in which case you do not need building control approval. more information on stove installation.
The Pot hanger attaches inside the top of the liner and has a larger flange at the top that rests on the top of the chimney pot. This lets you install a chimney liner without removing the chimney pot. A top insert is needed if using a pot hanger.