Hot water?

We had a nice trip to the seaside the other day to let Jac have a run. He is pretty well recovered from his cruciate ligament injury (touch wood).

Our eldest daughter and family have just moved house. I was talking to her on her mobile phone and she informed me the move had gone well but they had no phone line,  no internet fitted yet and no hot water or heating.
Enquiring more I asked why no hot water. She said she didn't know how to work it.
"Well." I said." What sort of heating system is it? Oil? Gas? Electric?"
"How do I tell ?" She replied.
Good job winters a way a way.