Wood burner not behaving

[Bethom89]

Hi guys

I’ve been having a battle with my wood burner. Ever since new it’s not drawn very well. It’s a twin insulated flue pipe which goes through the wall and up the side of the house. Has plenty of length and a cowl on top.

I’ve tried opening slowly, opening windows, opening vents full prior to opening etc etc (all the things you read on forums) Once going properly it burns very hot and well. But when opening the door lots of smoke still come out.

I’ve had a guy come and sweep it on Friday who said it’s the cleanest he’s swept so that isn’t the problem. He said try it without the baffle plate which did actually improve it. However last night the flue pipe above got too hot and burnt the paint off filling the house with smoke ‍♂️ And resulting in the fitting of that and the adaptor to now be loose.
I forgot to mention I’m a bench joiner so all wood is around 10% MC max and all clean.
Any advice or suggestions would be greatly appreciated so I can sort the bloody thing out. I’ve attached the type of fire

Lewis

 

[DAKSY]

How tall is "plenty of length?"
From the on-line Product Description:

• Flue Outlet: Top, NB This stove requires at least 5m of flue to operate efficiently and also should NOT be used with an Anti Down Draft Cowl, only an open cowl should be used.

 

[Ludlow]

A sweep told you to remove the baffle? Really? All the heat that was supposed to stay in the stove and ignite the secondaries just went up the flue and cooked the paint off. Might have even ruined it.

 

[Nigel459]

Hi Lewis,

I have a similar "modern" stove with what they call a vertical firebox (Scan A10). It has a beautiful fire view, best I've ever seen, and burns efficiently, hot and clean. I love it. Due to the huge glass viewing door, if I don't open it gradually, I can pull smoke in the room. I know you say you've tried opening slowly so I won't suggest that; however, I will explain what it takes with mine to avoid smoke.

My best strategy is to build a fire, usually a "top-down" version, that does not require opening the door to poke, prod, or add wood, until hours later, in the late coaling stage, when there's really not much smoke. Silly sounding, but true. After all, if the door stays shut there's no way smoke escapes. Ha. This has come with time, figuring out the wood and the best way to load it. Dry wood is great, which you have. You will figure it out, have faith.

IF I need to open during a burn, to pop the corner of a log off the glass or adjust or whatnot, I can usually do it by opening the door very very very slowly. Like 2cm, wait 10 sec, 2cm, wait, etc... I have 8m+ of flue, so the above question regarding how much flue you have is a good one.

I hope you can figure it out.

10% is very dry wood so be careful with it. No wonder the paint burned off your pipe without the baffle with such dry wood. It is advisable to use the stove as it was designed and tested to be used. It's very strange that you were advised otherwise!

Good luck.

Hi guys

I’ve been having a battle with my wood burner. Ever since new it’s not drawn very well. It’s a twin insulated flue pipe which goes through the wall and up the side of the house. Has plenty of length and a cowl on top.

I’ve tried opening slowly, opening windows, opening vents full prior to opening etc etc (all the things you read on forums) Once going properly it burns very hot and well. But when opening the door lots of smoke still come out.

I’ve had a guy come and sweep it on Friday who said it’s the cleanest he’s swept so that isn’t the problem. He said try it without the baffle plate which did actually improve it. However last night the flue pipe above got too hot and burnt the paint off filling the house with smoke ‍♂️ And resulting in the fitting of that and the adaptor to now be loose.
I forgot to mention I’m a bench joiner so all wood is around 10% MC max and all clean.
Any advice or suggestions would be greatly appreciated so I can sort the bloody thing out. I’ve attached the type of fire

Lewis

 

[Bethom89]

A sweep told you to remove the baffle? Really? All the heat that was supposed to stay in the stove and ignite the secondaries just went up the flue and cooked the paint off. Might have even ruined it.

Hi Ludlow,
Yes so I presumed it ok ‍♂️ Obviously not!

 

[Bethom89]

How tall is "plenty of length?"
From the on-line Product Description:

• Flue Outlet: Top, NB This stove requires at least 5m of flue to operate efficiently and also should NOT be used with an Anti Down Draft Cowl, only an open cowl should be used.

Hi Dasky, there is just over 5m of flue. I have attached a picture of the cowel that’s on

 

[Bethom89]

Thanks for the comments so far guys. I’m going to try it without the downdraft cowel at the weekend and see if that helps. If so I will by an open cowel. The baffle is back in place now but performance has gone back to it was before (obviously)
Thanks for your comments Nigel, I’ve unfortunately tried opening it as slow as possible but still give loads of smoke back once open ( even with a window open)
Lewis

 

[Nigel459]

Improving draft will help of course--I hope the cowl makes a difference for you. If not you could also try adding length to your chimney. You will often read on here to simply "try it out" you can just add cheap connector (black) pipe to determine how much you need for an improvement.

Worst case is just getting a fire built that won't need to be opened up till it's down to low coals.

Good luck, looks like a lovely stove!

 

[DAKSY]

A couple of questions come to mind, since no one has addressed the negative house pressure issue...
How tall is your home?
What floor is the wood stove on?
Are there other appliances, like range hoods, exhaust fans or dryer vents operating at the
same time you're opening the door on the stove?

 

[Bethom89]

A couple of questions come to mind, since no one has addressed the negative house pressure issue...
How tall is your home?
What floor is the wood stove on?
Are there other appliances, like range hoods, exhaust fans or dryer vents operating at the
same time you're opening the door on the stove?

Hi Dasky,

Of course I do have a hood and bathroom fans etc in the house.
I can’t say if it’s worse when they are also turned on. I can however say it’s still bad without them on as I light it before showering/ cooking usually.
The house is a standard two story home with a pitched roof and loft space. The stove is downstairs in the kitchen.
Apparently that cowel isn’t a anti downdraft cowel also so that shouldn’t be the problem.
Apart from adding more length I’m struggling with any more ideas?

 

[Bethom89]

Hi everyone, today I have added 500mm of flue pipe to try and improve the draw.
Sadly that has not happened. I’ll explain more about the fire conditions.
I have no trouble lighting it with a fire lighter and a good pile of kindling. With a fresh pile of wood on it burns with big flames and very hot. Then dies down to a smouldering kind of burn until more is added. The fire is in the kitchen with extraction etc however I have the window open and nothing turned on tonight and still plumes if ash and smoke pour into the room when I open the door (no matter how slowly) do I now look at changing the cowel? Fitting a direct air supply? Or get rid of the damn thing. I’m losing faith in what I’ve previously loved having in my old house.
Lewis

 

[DAKSY]

What kind of neighborhood are you in - i.e., a residential area
where all the buildings/homes have roofs that are at about the
same height from the ground, or are there lots of
taller buildings or trees in the immediate vicinity of your home?
Which direction does the prevailing wind approach your home?
Does it blow towards the chimney side of the home from an open
area or does it have to pass over buildings or trees which could
cause the wind to blow DOWN onto the chimney location?
I know I'm fishing here, but there HAS to be an explanation to
your issue & a solution, as well...

 

[Bethom89]

What kind of neighborhood are you in - i.e., a residential area
where all the buildings/homes have roofs that are at about the
same height from the ground, or are there lots of
taller buildings or trees in the immediate vicinity of your home?
Which direction does the prevailing wind approach your home?
Does it blow towards the chimney side of the home from an open
area or does it have to pass over buildings or trees which could
cause the wind to blow DOWN onto the chimney location?
I know I'm fishing here, but there HAS to be an explanation to
your issue & a solution, as well...

Hi Dasky thanks for your reply, I’m on a road with houses only on the same side as mine. We are all detached by a few meters. There is a woodland at the back of the house and the trees are higher as the house is built into the hillside if you know what I mean. In terms of wind direction I’m not overly sure on that but can investigate over the weekend.
Lewis

 

[Pertzbro]

How much is more pipe for you £ wise? Looks like you only increased the length of your pipe 10% or from 5m to 5.5m. I'd keep going with more pipe if feasible. Seems like a drafting issue that can only be fixed with more pipe. I'm not so sure having an outside air kit for combustion air will help much with a poor draft. What are the temperature conditions while burning? Is it cold enough outside to have good draft? As Nigel459 stated, he has 8M of pipe and still has smoke issues. Could be those modern small designs of the European stoves as well?

Our American stoves require 4.5M MINIMUM. Typically 9M or more is too much draft and will overheat the stove, by North American standards/stoves.

 

[Bethom89]

How much is more pipe for you £ wise? Looks like you only increased the length of your pipe 10% or from 5m to 5.5m. I'd keep going with more pipe if feasible. Seems like a drafting issue that can only be fixed with more pipe. I'm not so sure having an outside air kit for combustion air will help much with a poor draft. What are the temperature conditions while burning? Is it cold enough outside to have good draft? As Nigel459 stated, he has 8M of pipe and still has smoke issues. Could be those modern small designs of the European stoves as well?

Our American stoves require 4.5M MINIMUM. Typically 9M or more is too much draft and will overheat the stove, by North American standards/stoves.

The flue is expensive as it’s a twin wall insulated pipe. To be honest I’ll struggle to go much higher without additional structure supports (not to mention they are an eyesore) the outside is around 9•c tonight but struggle the same when it’s 0 or below.
Am I going down the wrong road considering a spinning cowel?
I don’t have a thermometer on the stove but it burns very hot with new fuel and cools down once the flames die down obviously.
Lewis

 

[Woody Stover]

I’m losing faith in what I’ve previously loved having in my old house.

Are you saying that you had this same stove in your old house, and had no smoke roll-out problem there?

the house is built into the hillside if you know what I mean. In terms of wind direction I’m not overly sure on that but can investigate over the weekend.

If there is usually wind coming from the opposite side of the hill you are on, the wind will come over the top of the hill, then blow downward, which will hurt draft (draught.) I'm not sure if there is a remedy in that situation..?? Do your neighbors burn wood? Do they have problems?

today I have added 500mm of flue pipe to try and improve the draw.
Sadly that has not happened.

That's not much. Also keep in mind that you may need more chimney height than recommended in the manual, since the majority of your chimney is outside and stays cooler than an inside chimney, decreasing draft further.
If other solutions don't work, you may have to go with a different design of stove that is less prone to smoke roll-out (draws more easily than your current stove.)

 

[wooduser]

A sweep told you to remove the baffle? Really? All the heat that was supposed to stay in the stove and ignite the secondaries just went up the flue and cooked the paint off. Might have even ruined it.

See, this is my problem with "expert" opinion. It can be wrong.

Better to rely on the written specifications and installation instructions provided by the manufacturer, is my theory.

And just because an installer puts it in doesn't make it done right, either.

I suggest that the best place to start is by carefully reviewing the installation and operating manual for a piece of equipment.

A careful reading of those manuals provides the basis for a good discussion with experts as well. If they suggest something that contradicts the recommendations of the manufacturer, they should be able to explain that, if it's to be done at all.