How to clean cooker extractor fans?

[brexitstinks]

I've tried hot soapy water and put them in the dishwasher and also dettol spray, but they still look and smell greasy. What can I do?

Stardrops from Wilko? It's cheap and great for a variety of jobs with different levels of dilution. i'd spray on a 50/50 solution and leave for an hour, then into the dishwasher.

Sugar soap is brilliant for shifting grease.

If you mean the mesh bits- remove them and put them in a glass dish, spray on mr muscle oven cleaner and leave for a couple of hours then scrub with a hard bristle brush to get in all the crannies.