An American-style “frost free” freezer which was icing up. The bottom drawer was frozen solid.
Having freed up the drawer, we can access the frost-free mechanism. These work by draining moisture through a small hole at the bottom, where the escaping water hits a heated element at the back of the fridge (here it’s just a metal plate which utilises the compressor pump’s heat) and evaporates the water into the room.
In this instance the escape tube had become blocked, and once this happens there’s no chance of it working properly without a thorough defrost.
I charged £30 for this, which included a good clean-up of the fridge and freezer shelves/walls etc