Another contributor, Gervais Sawyer wrote this today...
Boiler fans rarely fail because of the windings. It's usually the bearings wear out. Whether ball bearings or bronze bushes, both are available at your local ball bearing merchant. The ball bearings must be high temp types and should cost about £8 each. Bronze bushes (usually spherical self-aligning types) cost less that £1 each. All you then have to cost is your time fitting them. As for the switch, usually the hose to it perishes. If it is a microswitch with a flap, that is easily replaced with a standard microswitch from RS Components.
Peccavi, January 2009
