If it's the compressor that has been noisy and is causing it to trip, you would be looking around £300 for a new compressor and regas.
If it's the defrost heaters causing the problem, you're looking around £200 to repair it.
If you have good diy skills, take the rear panel inside the fridge off.
(bottom rear inside the fridge).
disconnect the wiring at the plugs on the rear wall.
Plug in and see if it trips.
If it does, do the same inside the freezer.
If it still trips, it's likely the compressor.
If it doesn't trip and the compressor runs, whichever one is disconnected is the cause of the problem.
Check it out, see what you find and get back to me.
Obviously, if you cannot do the work yourself, you'll need to get someone in to do it for you.
Hope this helps