Can a soot smell be remedied before and during rainy days? Odor sometimes very strong, even unbearable. Note: I have for one year Ionela heating.
It is unlikely that the phenomenon comes from your heating system since it does not use a chimney... Generally the soot odors come down in the house by inversion of draft of the chimney when it is no longer used to heat, under the effect of the VMC (whose air inlet mouths may also be insufficient) or the kitchen hood, which put the parts in depression.
You can install a tilt flap inside your chimney flue located close to the fireplace, which you will close when your chimney will not be used and that will prevent odors from spreading in the house.
Remember to have the duct swept at least twice a year and complete with a cleaning approximately every two months during activity.
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