you will need to remove the front cover.heater screwed to caravan floor.disconnect gas on underside of caravan heater.disconnect flue pipe.lift heater forward and disconnect electrics making note of connections.lift whole heater out.Explodes diagrams of heaters are available online for free.fan attaches to the back of the heater.undo screws and remove again noting connections.split heater blower assembly to gain access to motor bearing.regrease and reassemble.
Gary
February 2012