Woodburner Draw

[Burnerman]

Good posts, CW.....you refer to 'spilling'.
I'd suggest to the OP that he continues testing with smoke pellets rather than lighting up every time.
John

 

[foxhole]

Think about it... extractor fans extract air from rooms. Stoves do the same. If there's an extractor fan or 5 running, then the stove is competing with that to get a draw -- you will get smoke pulled into the room if it's a strong enough force. I have noticed over the last few years that having the kitchen door open (into the living room where the stove is), having the extractor fan on and lighting the stove results in a poorer draw.

Any Google search on this will pull up stories of people sharing the same experience.

My wood burner has not been affected by fans , it draws air directly from outside thru rear vent .

 

[Burnerman]

By far the best type, if installation allows.
John

 

[cwhaley]

My wood burner has not been affected by fans , it draws air directly from outside thru rear vent .

Does the OP have a rear vent? If so, this puts the issue almost certainly down to the flue. Need to know this before we can offer accurate advice.

 

[Burnerman]

I'm pretty sure this is a conventional air in room fed stove with the option of a top or rear exit flue. The hinged baffle should allow easy access and with the correct sweeping rods, even the rear exit should be cleanable from within.
John

 

[Lower]

Have A total of 5 extractor fans in the house , why is that significant?

Where does the air for the woodburner come from? Is there a dedicated air vent in the same room as the woodburner and is it open?

If not, then the woodburner has to draw air from the house which means that the air drawn from the house has to be replaced from somewhere and will leak in through any opening there is. If the house is old and leaky, you won't notice it. If the house is well sealed, then it can be a problem.

If you turn on an extractor fan then the situation is reversed and it is quite possible that the extractor fan will draw air in through the woodburner flue. If the woodburner flue is full of smoke then the smoke (and any CO) is going to get pulled back into the house.

 

[subzero]

Thanks to all for the replies and suggestions, much appreciated.

To clarify, there are no extractor fans in the room. Nothing has changed and the burner has been operating perfectly for the last ten years.

There is no actual baffle in the Charnwood (never had one).

We also have a Morso Squirrel in another room (separate flue liner obviously) which has no issues.

I suspect there must be a blockage toward the top of the flue, so we'll have to get a professional in to see if they can resolve.

 

[Burnerman]

https://www.fluesystems.com/shop/Chimney_Brushes.html
This is where I get my flue cleaning stuff from - the best by far, especially the very flexible thin rods and nylon spiral brushes.
Surely the Charnwood has an inclined baffle plate, above the actual fire?
John

 

[subzero]

The baffle plate was never supplied with the stove when we bought it, but is available as a separate item (for a very small King's ransom).

We've used a "Chimney Typhoon" system (neon coloured brush) to sweep. Seems to be a good product, but perhaps a smaller brush is required near the top of the flue.

Thanks for the link.

 

[cwhaley]

We also have a Morso Squirrel in another room (separate flue liner obviously) which has no issues.

I suspect there must be a blockage toward the top of the flue, so we'll have to get a professional in to see if they can resolve.

I'd put money on that after ten year's of use. It may also be a possibility that liner has split at some point or the cowls have moved.

If the two flues terminate at the same point (as my open fire and stove do) then when one is in use after being lit, the other (cold flue) can pull the warm air down. Currently my open fire flue pot is at an angle (fell to one side) and it points directly into the flue for the stove -- if I light the fire first it then becomes very, very difficult to light the stove as smoke billows out and into the room. I have to light the stove first then the fire.

 

[foxhole]

Where does the air for the woodburner come from? Is there a dedicated air vent in the same room as the woodburner and is it open?

If not, then the woodburner has to draw air from the house which means that the air drawn from the house has to be replaced from somewhere and will leak in through any opening there is. If the house is old and leaky, you won't notice it. If the house is well sealed, then it can be a problem.

If you turn on an extractor fan then the situation is reversed and it is quite possible that the extractor fan will draw air in through the woodburner flue. If the woodburner flue is full of smoke then the smoke (and any CO) is going to get pulled back into the house.

Stove has permanently open vent to rear thru wall. Fans has no effect on it .

 

[lostinthelight]

What size is the flue liner?

 

[subzero]

5" liner. Approx 9m height of twin wall flue. I wonder if it's worth getting hold of an inspection camera, if it's possible to get one with cable that length...

 

[bernardgreen]

I wonder if it's worth getting hold of an inspection camera,

Many good chimney sweeps will have a suitable camera and rods to enable then to inspect the entire flue.

 

[lostinthelight]

5" liner. Approx 9m height of twin wall flue. I wonder if it's worth getting hold of an inspection camera, if it's possible to get one with cable that length...

I think ive seen a usb one that length but suspect you may have to tape to your sweep rods to get it up there, often there is a buildup where the flue ends at the cowl
Charnwood say up to 7” flue and 5” can be used under certain conditions and if used it should be swept twice a year.
Is the stove approved for smoke control area ie, has a defra kit area which it would need to be for connection to 5” if you wanted to burn wood...but fine for solid fuels.
The stove should have a baffle as standard which they may refer to as a hinged throat plate as without one, it would be very inefficient
Can you post pics of the set up or draw how the stove connects to the liner and where sweeping hatch is?