We had some smoke/soot damage in our house in the recent SoCa wildfires.
Our insurers (State Farm) had the interior of the house cleaned and washed
by professional cleaners.
After they cleaned the house, they had a commercial duct cleaning outfit
(Airtek) clean the heating ducts.
A few hours after they had cleaned the ducts, we noticed an unsightly layer
of black, gritty soot coming out of our heating vents. It was noticeable on
paper that had been lying on the floor under the vents.
Airtek has been back four times and kept cleaning the ducts, and still there
is soot coming our of the vents. Now there is less gritty soot coming out,
but more small patches of thin plastic overlaid with soot.
Any ideas what the problem might be?
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