My furnace seems to be blowing a black sooty like layer of dirt through the vents. My walls are ruined. Over the phone, 3 different professionals suggested that the combustion chamber may have a crack and a new furnace is necessary. But after a visual inspection the furnace is OK. I bought a better filter (3 month) and after one week it was black. Any ideas? I have 2 CO2 detectors which have not alerted me to any danger signs. I want to do some painting but not before I fix this.
Answer:
You probably need more than a visual inspection of the furnace and don't be surprised if a new furnace is in order. This is not a safe situation and you should address it as soon as practicable.
