hi Jan Wan
I think that they have the right to try and repair it first. I would consider yourself lucky they are going to reimburse you for the food instead of making you claim off your insurance.
I had a brand new washing machine that wouldn't work. I had to wait a week for an engineer to call out. He said the electrics were not connected properly. It wasn't wired up to start and the wires to the door to keep it shut during use wasn't connected so the door could of been opened at any time and hot water could of scolded someone. He also found loose live wires.
He connected it all up then gave the whole machine a thougher inspection to make sure it was safe. I told him I was going to complain and ask for a new machine. He advised me to keep this one as I now knew it was safe and connected properly. If I got a new one I could not be certain it would have similar problems.
I decided he was right so kept the machine but sent a letter of complaint in with the job call out number included so that comet could check the problems.