I live near Chicago, we have almost a foot of snow on the ground, we have freezing fog and more snow falling. My carbon monoxide went off earlier. There is no way to get to a hotel. We turned the heat off and opened a couple windows a crack. Now we will see how cold it gets in our townhouse. We will see just how well we manage to keep warm until morning when we can get someone here to check it out. I figure we will turn the heat on for ten minutes every hour or so, leave the windows cracked and bundle up under all the blankets we can find. I am wondering if the furnace vent is clogged with ice and snow. The furnace is only a about 4 years old.