We purchased a three year old two story earlier this year with a gas furnace. Since the weather has been cold, I've noticed that when I come home in the afternoon and the vent coming out of the roof is steaming nicely and none of the other houses in my neighborhood are doing this.
This morning it was in the twenties and the vent was steaming really good, but again, no other house in our subdivision was doing this.
Is this a potential problem? For a house of this age, it does seem strange that it doesn't seem to warm up as nicely as we would like. The upstairs is hot in the summer and cold in the winter and although I realize this is typical of a 2 story, I think it should be better.
How old is the furnace?
If you have a high efficient furnace you will get steam.
Sometimes contractors vent the Piping up thru
the old chimney.
If it is a catorgory 2 furnace RE: Mid.
Then make sure you have it vented with B vent and that there is a liner installed.
Clarkson Comfort Zone Heating and Air