Cooker extractor into chimney?

When I did this i simply put in a copex liner intended to be used for gas appliances and connected the extractor straight to that. It works a treat and you don`t have to worry about grease or moisture getting into your chimney.

In article , John Woodhall writes

I certainly wouldn't do it without a liner.

Just to update the situation! I have removed the plywood blanking sheet and lo and behold I have found an old (20s 30s) extractor fan in a the hole where the flue used to be. The chimney is clean, obviously swept many years ago and has a good draught. I personally now cannot see a problem in fiting an extractor, but will listen to any advice/suggestions on offer. Cheers

In article , johno writes

My suggestion of using a liner is because you are taking warm damp air and dumping it into a cold chimney. I think it is inevitable that condensation will occur which may or may not cause problems in the future. The safe bet is to fit a liner, single skinned copex types are cheap, ok not as cheap as nothing but that is what I would do.

I know you said that the air would not be excessively steamy but if it wasn't hot and damp then you wouldn't need an extractor ;-)

HTH