Electrolux ER7831 l – not cooling

For a long time now my fridge freezer has suffered from a large build up of ice in the fridge compartment (mainly at the top back former on the right but also in other areas)

We tried changing the thermostat about a year ago but the ice build up continued.

Now, after the latest defrost, it seems to have stopped working altogether ( it did work for a few days after being switched back on but gradually became less and less cool). The freezer, which had always seemed fine, has also stopped working. There is power to the unit and the light comes on but not much sound from anything so it doesn’t seem like the compressor is running.

Any suggestions gratefully received. Thanks

Product no. 925694601
See no. 2430205