its a possibility
but its a good sign if DHW & CH are still working
FAN bearings/motor might just need regreasing with high temperature lubricant to reduce FAN noise
would check FAN delta pressure & compare with manufacturers recommended tolerance before deciding to change FAN
manwithnoname
May 2012
Automatic Answer
We may have found other answers which could help you.
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix home heating systems.