We heat our 5 year old bungalow with an air tight wood stove, with electric baseboard as backup. The stove has been in almost constant use since November as it is very cold where we live. We burn hardwood exclusively except for softwood kindling to start the fire should it go out. The pipe from the stove is 6" double wall to the ceiling for a total run of 6 ft. The chimney is a SS insulated at 7" diameter through the attic and extends about 10 ft above the roof line to clear the ridge. It has a special cap that prevents downdraught. The chimney is cleaned once per year in the fall before the heating season. We were away for 2 days and when we arrived home we immediately started a fire. The next day when we went outside, we noticed the snow in the front yard was littered with many small black specks that were not there when we came home. This had to have come from the wood stove when we first started it. Is this a sign of a problem? Should I be concerned? Thanks for all responses.

It just sounds like a creosote burn off. Did you bank the fire back before you left? If you did a bit of creosote will build up and with a good hot fire flack off and drift up with the smoke

Thank you, TheSavage, for your response. Yes I stacked the fire before we left and it did burn out in probably 3 or 4 hours. We then lit a fire that was quite hot to bring the temperature up from the 16 oC (61 oF) that the baseboards are set to maintain, so I suspect that what you said is precisely what happened. I had hoped that it did not mean that I had to clean the chimney now as it is rarely above -15 oC (5 oF)in the daytime. As soon as the snow is off the roof, I will have the chimney cleaned. Thanks again.

You will not need it cleaned. It's a normal part of running a wood stove.
The main reason for creosote build up is running a banked stove -- the problem is worst when the stove is to big for the space to be heated.

Thanks for the responses. As it turns out, I had to clean the chimney a few days after my last post. Our setup seems to let a small downdraft into the house when I open the wood stove door to put wood in, when the chimney needs to be cleaned. Actually, the chimney was quite clean when I opened it, but the wire mesh in the rain cap seems to get plugged twice or more per heating season. This reduces the draw of the chimney and we get asome wood smoke into the house. I have cleaned the chimney and all is OK now, and should be until the end of March or mid April when the season is over. Thanks to all.