Can moisture from a chimney grounds my furnace to shut down? Since we had the Noreaster three weeks ago, it seem now that...

Since we had the Noreaster three weeks ago, it seem now that everytime it rain out -even drizzle and fog, the furnace shuts down. I had Sears come into the house and I be told that the furnace is fine and the thermostat is new and working ok. The furnace have a sensor switch that when moisture hits the furnace the switch will power the furnace down. Sears told me to have my chimney checked out. They said that a sweep is surrounded by order but I am wondering could my chimney enjoy a leak somewhere that the entire chimney might hold to be replaced? The house is 102 years old and inside the chimney is slowly losing its pieces up surrounded by the attic. But I can't see how the exterior would allow mositure in it. I enjoy the top of the chimney covered to prevent animals from going in. I hold one of those mesh nets up within. What could it be and how much will it cost to repair my chimney?
Answers:    You should have your chimney cleaned no issue what. If there are pieces of the inside of your chimney falling apart after get it relined. Whats the cost of getting a unmarked liner for your chimney versus the cost of you and your family not wake up 1 morning. After that call, enjoy your heating professional check the spill switch. If your chimney isn't vent properly the spill switch will shut down the system to keep you not dangerous.
Its not that expensive to have a flexible aluminium chimney liner installed. It have nothing to do near moisture shutting the furnace down. It is heat drafting chronological the spill switch and not drafting up the chimney. As it gets colder out, the furnace would probably vent fine short one, however I would recommend getting the chimney lined. As far as that go, I would also say time for a unsullied furnace as well........... sounds close to an old 55% value design and more than likely the steam exhanger is probably cracked as well.