When I took my chimney cap off today I noticed on the inside was some shiny black tar. it was a little sticky in some areas. There was also black on the inside of the pipe but not sticky. I've only had about 4 weeks total of burning wood through the new pipe. I know I have good wood I've had it burning over a month the wood burns up very fast. I took the bottom tee cap off and the pipe inside have a light gray dusting on it of dry nothingness. Why does the top cap have dark sticky film. should this already be this way. Should I be concerned. Or is this because the top of the chimney is the coldest and it forms there first. Will this start to travel down into the pipe from the cap or just stay near the top only.