Hi all i have a back vented wood fire inside an exsisting fireplace i dropped a 6 inch flue inside the exsisting brick chimney and finished it off flush at the top should i extend the flue with a hat woild it make a difference

 

Your going to have to tell us more about what you have. First, what is a "back vented wood fire"??? Do you mean a wood stove or insert? How is your flue insert terminated at the bottom? Is there still a damper?

 

My apologies it is a wood heater with the flue connection coming out from the rear with tee piece one side up the chimney the other about 6 inches long with a cap for cleaning sorry cant figure out how to add pic

 

basically want advice on weather to extend flue with hat higher than where i have finished it off to improve operation
Regards
Rob

 

So, you lined your chimney with a 6" pipe. Does it go straight through and connect directly to your stove or is there a smoke shelf or damper in there somewhere?

What type stove do you have? Is it catalytic, a modern non-catalytic or an old steel box wood stove?
When does the stove have trouble drawing? Is it just during start-up or does it also happen after the fire and stove have gotten up to temp?

 

Hi mate yep straight in and up no damper or anything like that im guessing you call it old steel metal box only seem to have on start up always had that trouble flue is cleaned regularly also i get wind pushing smoke back down on certin very windy days
Rob

 

Almost all fireplaces and stoves have trouble drawing when first started. "Draw" is created by the hot gasses rising up the chimney. Until there is enough heat being generated there isn't much to make the smoke to want to go up the flue. That's why I was asking if you had a newer low emission stove which really need a good fire or bed of coals to reliably draw well.

Wind is a tough one. A different chimney cap probably would help but you may still have trouble occasionally. Smoke going up the chimney is powered only by hot gases rising so it's easy for a strong gust of wind to overpower it.

Another thing to keep in mind is that your flue is out the back, not the top. When the door is open there isn't a lot that makes the smoke want to go out the back versus the front.

 

The other side of air flow is having a source of make-up air coming into that room. If the room is too tight then air has trouble going up the chimney. Test it with a door open or window lower than the stove.

I see the house in the background that looks to be higher than this chimney. That can often create downward air flow as currents flow over the other roof. A lot of work, but I don't see a down side to a taller chimney.

Bud