Hi
I've got an Airflow 4" window-mounted extractor fan in the bathroom. Last winter it started squealing and I used to tap it and eventually it would stop. The squealing stops in spring. It restarted its howl a couple of weeks ago. Tapping and banging doesn't work this season.
Today I took the thing apart, spent an hour cleaning every bit of grimey dirt from it, put it back together and reconnected. When 'hanging loose' and rotated about 90 degrees from its installed position it doesn't squeal: encouraging. I fitted it back into the window and it started squealing again!
Any ideas how to fix this? Any ideas why the bloody thing squeals only in winter?!
Cheers for any help,
Emma