My old lennox hvac transformer blew, it was a Basler be11349rcd29, 120volt to 24 volt 50/60 cycle, it has a white and a black wire comeing from it, I want to add a fuse to the correct line, I don't know much about electric stuff, how or where do I find a correct and affordable replacement part, and to where and how do I attach the fuse, or would there be a replacement unit with a fuse box on it, a good useful part number replacement would also help,
Thanks

Do you have a Radio Shack nearby? If so, go buy a 273-1512 heavy duty transformer, a 270-1281 inline fuse holder, a pack of 270-1005 one amp fuses, and maybe 64-3057 assorted wire connectors. These are out of an old catalog, so I can't promise they haven't changed the part numbers. Also, make sure if the old transformer has a amperage marked on it, it isn't over 2 amps output.

If you don't have a Radio Shack, you may be able to find the stuff at a hardware store or home center. Auto stores may have the fuse holder you need. The part numbers I gave you are for the traditional 1/4'' fuses. You may have to buy 5 mm ones now. Just make sure the fuses and holder match.

Shut the power off to the furnace. The transformer should have 2 black wire on each side, plus a yellow wire one. On the side with only the 2, connect one to the white wire from the furnace. Connect the black wire from the furnace to the fuse holder, and the fuse holder to the other wire on that side. Put in one fuse. Ignore the yellow wire, maybe capping it with a wire nut so it never connects anything. Connect the 2 black wires on that side to the red and blue wires to the furnace controls. You have a new, fuse protected transformer likely all for less than $20.