Ticking and cold running log burner

[gotoPzero]

I have 2 identical log burners, one in the lobby and one in the kitchen.

I light them exactly the same, top down. Use the same logs etc.

The one in the lobby runs perfect, after 30 mins I shut the air down and it holds about 250c from that point on.
I can carefully open the door to put more logs on when its down to coals and it will catch straight away.
It runs silent, once its up to temp it just runs and only "ticks" when its out of fuel and is cooling down by which time I am in bed so dont care!

The other in the kitchen is the problem.

Light the same way, air right open. Generally goes really well, temp comes up to about 200-220.
Close the air down and it basically nearly goes out. The whole time ticking non stop; it then seems to go up and down temp wise a lot.
Usually settles about 150c. Which IMO is not hot enough.

If I open the door I almost always get smoke in the room, even with the air right open.

Where am I going wrong? My MO is the same with the other and I have no issues.

The only difference is different chimney stack.

Its at the point where its almost not worth putting it on. If it gets really hot and up to temp it does not last long and dies right back.
The constant ticking makes it quite annoying too.

I had it on last night and it ran alright but this morning had a look in and half a log was just sat there unburnt.

So something isn't right.

[geeks]

When was the problem child last swept? (I did read the OP and couldnt see this info)

[jfdi]

It does sound like a issue with the draw on the chimney, especially if you're getting a room full of smoke when you open it.
Get it checked for blockages.

[Desiderata]

gotoPzero said:

The only difference is different chimney stack.

There, you've got it.
Exactly what it is.
It could be the height of the stack, shape or condition of flue, type of chimney pot, type of diffuser, position with regards to roof/wind, obstruction, and more . Could you describe the chimneys and someone may be able to advise on solutions?

[balham123]

Assuming chimney is ok, try running it with a window in the room open. If it runs better it's because it's not able to pull in enough oxygen.

[DonkeyApple]

It's an air flow issue.

Either the flow rate in the chimney or less likely is that one is drawing air from the whole house and the other from just within the room.

I'd generally assume the former. Assuming both chimneys are the same height and have the same caps then one might start by considering the diameter or path. Assuming both are lined then they have the same diameter most likely so is one a bit blocked or does it have a bone linear path such as a dogleg where a first floor fireplace once was or stepping in from an inglenook? Does one chimney have trees that have grown next to it as that can impact the draw?

[Purosangue]

gotoPzero said:

I have 2 identical log burners, one in the lobby and one in the kitchen.

I light them exactly the same, top down. Use the same logs etc.

The one in the lobby runs perfect, after 30 mins I shut the air down and it holds about 250c from that point on.
I can carefully open the door to put more logs on when its down to coals and it will catch straight away.
It runs silent, once its up to temp it just runs and only "ticks" when its out of fuel and is cooling down by which time I am in bed so dont care!

The other in the kitchen is the problem.

Light the same way, air right open. Generally goes really well, temp comes up to about 200-220.
Close the air down and it basically nearly goes out. The whole time ticking non stop; it then seems to go up and down temp wise a lot.
Usually settles about 150c. Which IMO is not hot enough.

If I open the door I almost always get smoke in the room, even with the air right open.

Where am I going wrong? My MO is the same with the other and I have no issues.

The only difference is different chimney stack.

Its at the point where its almost not worth putting it on. If it gets really hot and up to temp it does not last long and dies right back.
The constant ticking makes it quite annoying too.

I had it on last night and it ran alright but this morning had a look in and half a log was just sat there unburnt.

So something isn't right.

sounds like poor ventilation in the room

https://www.hetas.co.uk/the-building-regulations-o...


if you have a log burner ticking over , it will leave deposits in the flue , you need to open up the vents and give it a good old blast to clean the flue , most modern 5KW stoves are more efficient if you have them set with air vents about 50% open

what flue systems have been installed ? is it a flexible liner or insulated / twin wall insulated flue does it exit out the rear of the stove or out the top , when did you have it cleaned it should be at least once a year .

you could get a HETAS engineer to inspect , either a smoke test or by checking the flue .

Edited by Purosangue on Monday 21st October 22:04

[gotoPzero]

So I am very much a novice,,, but I tried a few things that have been suggested here last night that seemed to work.

Re the stove in question, its defo not a straight shot out the chimney. As for what system of flu it is I have no idea, we only bought the house 4 weeks ago.

I believe the chimneys were done at the start of the summer.

So what I did first which helped a lot was crack a window when I was lighting, defo lit a lot easier and got upto 250-300c quite quickly and then seemed happy to hold.

I kept the air valve lower and that seemed to help too. Lastly I made 100% sure that it was down to embers before I opened the door and then cracked the window again before I opened the door and I did not get much (if any smoke this time).

I also threw in a few smoke pellets from my ninja and watched the chimney and it was defo smoking quite well.

Suspect its a combination of the chimney routing and the chimney being on a different aspect so wind hits it more.

The ticking was less, but not as good as the other burner still. I will give it another couple of goes if no joy will get someone out to have a look.

[MDT]

One other thing to ensure you don't do, as you say this is in the kitchen, if your hob extractor fan is on that will cause you to have a slight negative pressure in the room and so cause you all sorts of pain like smoke coming into the room with the door open.

[balham123]

gotoPzero said:

So I am very much a novice,,, but I tried a few things that have been suggested here last night that seemed to work.

Re the stove in question, its defo not a straight shot out the chimney. As for what system of flu it is I have no idea, we only bought the house 4 weeks ago.

I believe the chimneys were done at the start of the summer.

So what I did first which helped a lot was crack a window when I was lighting, defo lit a lot easier and got upto 250-300c quite quickly and then seemed happy to hold.

I kept the air valve lower and that seemed to help too. Lastly I made 100% sure that it was down to embers before I opened the door and then cracked the window again before I opened the door and I did not get much (if any smoke this time).

I also threw in a few smoke pellets from my ninja and watched the chimney and it was defo smoking quite well.

Suspect its a combination of the chimney routing and the chimney being on a different aspect so wind hits it more.

The ticking was less, but not as good as the other burner still. I will give it another couple of goes if no joy will get someone out to have a look.

If it's working better with the window open, you need to work out if you can fit a cold air intake to the room near the fire.

[DonkeyApple]

balham123 said:

If it's working better with the window open, you need to work out if you can fit a cold air intake to the room near the fire.

That's a good point. Especially an issue for more airtight new builds although they usually have vents in the window frames that can be opened.

[gotoPzero]

Just thought I would update.... think I have it nailed now. Its defo a combination of technique, right fuel and not rushing the top ups. Also wind direction seems to play a bit of a part.

So what I am doing now is, logs in, around 4 smaller logs. Light it. Open the air valve to max for at least 10 mins. Keep it going really well. Once it hits 300c then lower the air down to about 25% and it seems happy there and will hold 300c (thus not ticking anywhere near as much).

Then, once I hear it start to tick, thats when its usually down to a bed of coals. Open the air valve again, make sure extractor fan is off!! Then I move the stove fan too, that was causing a lot of problems when the door was opened. Then crack the door and open it *very slowly*. Put full large log on, maybe two even, and close the door slowly. Wait till new logs flash (1 min or so) and then lower the valve to 25% again and forget about it for another hour.

This seems to be working well for us now. I have also been told to leave a good bed of old coals as this helps. I was cleaning it out each time. This does indeed seem to be true and you get a faster first hot bed if its already on existing old coals. So I am just cleaning out once a week now.

The stove in the hall way is much easier to light and run and maintain a fire still, but I think I am not far behind now with the kitchen one.

Managed to get it so the glass is clear after a fire on both, which I think is a sign you are doing it right...

[DonkeyApple]

Excellent. It's quite an interesting case study as there won't be too many people who have a brace of identical stoves but in different rooms with different air flow parameters.

[loskie]

MDT said:

One other thing to ensure you don't do, as you say this is in the kitchen, if your hob extractor fan is on that will cause you to have a slight negative pressure in the room and so cause you all sorts of pain like smoke coming into the room with the door open.

This: plus I'm pretty sure it does(did) not conform to building regs to have an extractor in the same room.

But it's most likely down to the flu plus where it exits the house and surrounding roof(s).

[chrisch77]

I would guess your issue is that the flue is too large and/or cold for the kitchen burner and you can’t get enough hot air rising to counteract the falling cold air in the chimney. Do you think either stove has a flue liner fitted? If it is just exhausting into a clay lined chimney then that’s probably the root of the issue. We bought a house last year that has a burner fitted and it doesn’t have a liner and it can be a b’stard to get going dependant on atmospheric conditions.

[bennno]

gotoPzero said:

Just thought I would update.... think I have it nailed now. Its defo a combination of technique, right fuel and not rushing the top ups. Also wind direction seems to play a bit of a part.

So what I am doing now is, logs in, around 4 smaller logs. Light it. Open the air valve to max for at least 10 mins. Keep it going really well. Once it hits 300c then lower the air down to about 25% and it seems happy there and will hold 300c (thus not ticking anywhere near as much).

Then, once I hear it start to tick, thats when its usually down to a bed of coals. Open the air valve again, make sure extractor fan is off!! Then I move the stove fan too, that was causing a lot of problems when the door was opened. Then crack the door and open it *very slowly*. Put full large log on, maybe two even, and close the door slowly. Wait till new logs flash (1 min or so) and then lower the valve to 25% again and forget about it for another hour.

This seems to be working well for us now. I have also been told to leave a good bed of old coals as this helps. I was cleaning it out each time. This does indeed seem to be true and you get a faster first hot bed if its already on existing old coals. So I am just cleaning out once a week now.

The stove in the hall way is much easier to light and run and maintain a fire still, but I think I am not far behind now with the kitchen one.

Managed to get it so the glass is clear after a fire on both, which I think is a sign you are doing it right...

Coals? Is it a multi fuel or a log burner?

We leave the ash in ours, only needs clearing out 1-2-3 times each winter - protects the stove with ash bed.

As has been suggested, get it swept, you’ll need proof for insurance reasons.

Secondly don’t run an extractor fan in the kitchen when the stove is on.

[gotoPzero]

Ash you are right.

My next challenge is the other two fires we have in the house are open fires.

I have invested in a harth rug (?!) already.... but not quite got the confidence to fire it up yet.