Q: Jason – Our house gets smoky when our furnace runs while using the fireplace. The chimney inspector told us we needed to extend the fireplace chimney, so he did. We keep a window cracked by the fireplace as he suggested. that didnt fix it, so it still gets smoky in the house when the furnace runs. – LW
A: I would suggest a couple of things try while you are running your fireplace. these things should help you diagnose where the issue is.
1) Burn a fire in the fireplace with the glass doors closed first…if this eliminates the problem then the smoke is comming straight out of the hearth and getting into your cold air return for circulation around the house. Be sure to compare burnin with the doors closed first and then the doors open.
2) Try running your furnace on fan only and see if the problem is still there. If it is not then your furnace is drawing air from the outside that is smokey. If it is still there than it is certain that your cold air return is getting access to the smoke somehow.
3) If this smoke problem is intermittent then try to note which direction the wind is blowing when this happens. Wind can be a factor in the fireplace smoke wisping past the furnace intake. this is particularly an issue if you have a direct vent furnace.
4) Did your chimney inspector do a complete inspection of the interior of your chimney. Possibly a camera inspection should be done. If you have a crack in your chimney liner the smoke may be getting into the home that way. A damaged liner is a very dangerouse situation that will need immediate repair. – Jason