Black dust and soot around house especially in the bathroom and upstairs carpets

[Shell214]

I am experiencing black soot like dust around the house. While ago we had a leak in the roof during a storm. The water rushed in and went straight through our central heating boiler. We had this checked by a Gas engineer who said all was fine. As the soot started and got worse we phoned the Gas company again who sent out the same engineer who said all was fine again.
This situation is now bad we all have chest problems. The soot gets into my grandchildren beds, on sheets and everywhere. It's in the carpets so no point in getting new.
I have notices recently while we have not been using the heating that it is much better.
Please do you have any ideas.
Someone checked the flu and insulation for us. We do have the old flu left up there but he checked that too. I can send a pic of the dust
Thanks

 

[gas112]

Totally Stop using boileR immediately . Phone gas emergency service on 0800 111 999 and tell them you think you have fumes from boiler they will be out within the hour
and put a pic of your boiler up

 

[JohnD]

show us a pic of the dust when you rub it with your finger on white paper. actual soot is very fine and sort of greasy.

old houses often have black dust under the roof that can get washed down by a leak.

won't hurt to look.

 

[Shell214]

Thanks for your replies. I have phoned the Gasboard twice costing £50 a time to tell me that all is OK.
The house is about 30 years old. The boiler is nearly 8 years old.
The soot/dust seems to act more like dust when you try and pick it up.
I have noticed its much better lately since we stopped using the heating. I was washing a slick of black off the bath every morning. It is still around the bottom of the door of the airing cupboard in the carpet which is harder to remove
I will now try and send photos. If you magnify it on the China you can see better.
Boiler is Greenstar 15i system

 

[gas112]

If it seems you are getting soot when the heating is being on then this seriously suggests a problem with the boiler or its flue system .
Unless you are burning loads of candles in the house
gas emergency do not charge to come out

 

[Shell214]

we called out british gas , they checked the boiler , then the flue, and issued a certificate that the boiler was fine

 

[ianmcd]

Do you have CO monitors in these rooms where the black dust is appearing ?

 

[N8Miles]

Yea we do. In the airing cupboard and on the landing outside , both changed recently to ensure working correctly , sorry I am shells son