Creasote? Dripping down.
Back story:
We bought our home in Massachusetts exactly a year ago today.
Around November we had our oil furnace converted to natural gas. About 3 weeks later we noticed this stuff dripping through the moulding in our kitchen. We contacted a local chimney guy who took a look and realized there was never a liner installed during the conversion as mass law apparently requires. After contacting the furnace company they admitted they missed that and chose to fix it free of charge (also turns out no permit pulled or inspection was done).
We thought this had solved the issue. But over the last few months we noticed it slowly happening again, seemingly when it rained a lot.
But these past 2 weeks it has been constant. We can clean it and it'll look like the picture again by the next day. Heat causing melting?
The exposed chimney and the attic and basement show signs of this stuff, but not to extent of what's dripping from the ceiling.
Any ideas of what is causing this or how to fix it?