electrics box

Hello I am having some work done on my property, it is a ground floor flat converted in the 80's from a house. The electrical supply and consumer unit runs into my flat under the stairs to the first floor flat. To the left of the electrics are three existing pipes, a gas pipe which supplies...

Hi, In a cupboard under my stairs there's this white box. I've not paid much attention to it until today when I noticed it's warm. I don't remember it ever heating up. Before i call an electrician, any ideas what it is and if it should heat up? Thanks Larky