As many of you know, I had a Buderus oil boiler installed a couple weeks ago. Yesterday, I noticed a lot of blackish-green, oozy sludge dripping from the smoke pipe at the joint where it takes a right angle turn into the wall (and then up the chimney). Trying to figure out what the cause is and how to fix it.
Here's some additional background: in the past, when we had heavy rain from the south, we occassionally got a bit of water leaking from the same joint in the smoke pipe. I assumed it was wind-driver rain that got in the chimney. It was always just clear water. No sludge or soot in it. Just a few days before my new boiler was installed, I had the chimney cleaned and a new, bigger chimney cap put on.
For most of Monday we had rain and wind from the north due to hurrican Sandy. No problems then. In the wee hours Tuesday the rain and wind shifted to the south. It was late Tuesday morning when I discovered this puddle of black sludge on the floor, which had dripped from the smoke pipe.
I don't know for sure whether the sludge was due to rain getting down the chimney, or possibly condensation in the chimney due to temperature or atmospheric changes. Assuming it was rain, however, I am concerned that it was such thick black ooze, whereas in the past it was just a little water.
I had the contractor come back out and they put a baromic flue damper on, which they had not done before. They also sealed the seams of the smoke pipe with a high temp silicone, but that will just keep the ooze in the chimney, it won't really address whatever caused it in the first place.
Any ideas what could be cauusing this heavy black ooze? Is it a sign that my boiler is not set up properlly and/or condensing in the chimney? Any other thoughts? much appreciated.