If you have the fireplace smell in your home like rob does finding the source of the negative pressure and reducing it should solve the problem.
Attic fan fireplace smell.
New furnace boiler and or water heater.
Every cubic foot of air that passes into the attic is one more cubic foot of air to heat and one less for your chimney.
You don t want to stop using bath fans range hoods and clothes dryers though so keeping the damper closed when the fireplace isn t being used should help.
A change in your roofing ventilation attic fans.
Now place another fan in a window on the opposite side of the home.
This can happen when a dryer or other exhaust fan runs or if there are leaks in heating and air conditioning.
Attic and or whole house fans always bring fireplace odor in when used.
The smell or smoke coming down the chimney is a result of your house loosing too much air from the unsealed attic.
A neighboring structure s height increase.
In the basement the same problem can occur.
Whatever the situation is you are still left with a smoke filled room.
An attic hatch recessed can lights bathroom exhaust fans without baffle unsealed windows and air conditioning ducts coming out of ceiling are typical causes of the smelly problem.
The best way to get rid of this smoke is by placing a box fan in the same room as the fireplace.
Some causes of pressure change a fireplace smell in your home.
When you turn on both fans this will pull out the smoky air while you are drawing in new fresh air.