- sorry to see that Lee
Like Em. , I would check the sponge on top of the heater/air intake and then make sure there is no rubbish collected in the depths.
I'm not sure if there is also a drain valve/pipe down there - but if someone can confirm there is , it is probably blocked.
Not a fix but, I use one of the long shower capes that cover this vent as well as the hood - belt and braces.
Good luck with the investigation.....
James
