how to install a fan in a glowworm ultimate 80ff?

switch it off at mains
You have to replace the whole unit not just the motor. Remove the two rubber vacuum sensor pipes (red one is at the back)
Remove the two wires from the motor (think the red one goes to the lower connector from memory).

The fan unit is mounted and attached to a flat plate which is secured to another larger flat plate on the top of the boiler by 4 small crosshead screws.
Losen but do not remove the 2 rear screws (they go into a slot so no need to remove them altough if you do remove them it will allow you to lift the unit up rather then slide out which may reduce any disturbance to the fibreglass gasket/seal underneath)
remove the the front two screws.
Once the 4 screws out lift and slide it out - the aluminium flue pipe attached to it at the back should only be friction fit onto the wall outlet and the unit should come out with the pipe still on the unit.
If you dont have another pipe,, remove the old one and attach to the new unit.
Refit!
Be careful when you put the front cover on as it is easy to hit and snap the small cooling fan blades on top of motor. And if you snap them then your motor will probably die soon of overheating like my one did.
Hope that helps.

Cragster
November 2010