sooting in builders opening terminal

[desrob]

what causes excessive sooting enough to block openings in terminal ,this was on a gas fire it passed a spillage test but smoke entered the room on flue flow,this was a class 1 chimney with a liner.

 

[Billy Bob Bob]

knackerd burner,blocked lint arrestor,over gassing,wrong aeration setting worn jets to name but a few

 

[tamz]

Burning damp coal

Generally tho, a lack of air produces excess smoke which produces soot.

A gas appliance should never produce smoke/soot if it is burning properly. Failing the flue flow test indicates a partial blockage or more air needed. Can also be effected by the terminal position and the weather.

Are you sure there has not been a solid fuel in before?

 

[desrob]

Burning damp coal

Generally tho, a lack of air produces excess smoke which produces soot.

A gas appliance should never produce smoke/soot if it is burning properly. Failing the flue flow test indicates a partial blockage or more air needed. Can also be effected by the terminal position and the weather.

Are you sure there has not been a solid fuel in before?

used for back boiler before,it is none of gas man suggestions, could not get up on roof and to be honest i have no wish too,but from what i can see the terminai it self is black and looks blocked smoke seemed to be coming from around it, it also looks smaller than any other i've come across

 

[tamz]

If it was a back boiler in before it will be a class 2 chimney (5")

May be a GC1 or similar on top.

What type of fire is fitted

 

[desrob]

If it was a back boiler in before it will be a class 2 chimney (5")

May be a GC1 or similar on top.
View attachment 2145
What type of fire is fitted

yes that defo terminal,ilfe fire fitted 6.9kw

 

[Reg Man]

Has the opening got a smooth tapered transition on to the flue liner?

 

[desrob]

Has the opening got a smooth tapered transition on to the flue liner?

slightly off line,flue liner in front off gas fire opening,products probably going behind liner around builders opening then back up towards liner,will this mean repostioning liner

 

[Reg Man]

Something like this required

 

[desrob]

Something like this required

thankyou.

 

[tamz]

Using the existing liner is not always advisable as it can be hard to tell the integrity of it. Providing a class 2 is suitable for the fire, if you do plan on using it then the liner must be sealed properly at the bottom. No voids between the liner and chimney are allowed. There are different methods of achieving this but here is some guidance.


Personally, depending on the age of the building and condition of the chimney, i would consider pulling the liner out and doing a test on the existing brick chimney.
Also check the size of the catchment area. If it is too big (over 650mm wide x 475mm deep) reduce it by building up with brick or concrete block as too big an area can affect the draw.