log burner

[Staffbull]

Hi, I am thinking of opening up a fireplace I bricked up in the small living room and fitting a log burner in there, mainly due to the number of power cuts we are having and also it should save some money, we live on the edge of a large woods, and timber is in abundance, so with oil at 40p a litre we could do with cutting down.

with fitting a log burner can I get away with putting a S- steel pipe up a way (couple of metres up the chimmeny? or do I have to have it all the way to the pot, or do I have to have the chimeney re lined (currently red brick)

I have also seen them with small boilers attached, so could do with one of these to fit a rad in the downstairs and upstairs halls, I take it I would need to plumb it in using an open tank system for expansion? that would be a downside as the loft is WELL insulated so the roofspace would get the effects of the cold without the help of rising heat from the house.

I also miss the open fire !!

[robgraham]

I can't answer your chimney question, not my area. But the radiators

- you'll be able to gravity feed the upper hall one but I doubt you will be able to do that with the lower one, unless your living room is below the downstairs hall, so that would require a pump with all the associated gubbins.

Also remember that if you are adding a heat source that the radiators in the involved areas will require TMV's - and if you've made the same mistake as me, you'll find that the radiators you want to upgrade don't have isolators on them. In my case the TMV had gone faulty and it was either drain down totally or have a fight fitting the isolators using Arctic Spray ! Arctic Spray does work and actually in the current weather conditions for over twice as long as the tin says.

The other way to go is to do the whole integration exercise and either use a heatbank with two pairs of inlets, or fit a Dunsley Neutraliser as a heat blending tank from both sources. What you can't do is just to connect one to the other.

Rob

[Staffbull]

MMm sounds interesting, are you saying there is a way I can connect the log burner to my current sealed CH system (oil combi boiler), if there is that would be top banana!!

[Dave Liquorice]

I'm fairly sure the regs these days say you need a double skinned liner all the way to the top.

Open vented more from safety than anything else, get a good fire going an you'll be able to boil a cylinder of water in an evening... As you are also looking at this being a backup system the thing will need to work with gravity circulation not pumped or have any motorised valves. Gravity means that a rad on the same floor as the boiler isn't likley to get particulary warm let alone hot.

If you have an ordinary open vented CH system plumb it into the primary of that via a Dunsley Neutraliser (or similar) and when you have power you can heat your DHW and CH system saving oil. Without power you should still have DHW and CH upstairs.

[Staffbull]

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We have a sealed system here on the C/H, so I take it the neutraliser is out.

I'm thinking of fitting just the two rads in the halls (up and down) and using a pump for circulation, hassle would be thinking of running pipes all the way up to the roofspace for a vent/expansion tank.

I take it a double skinned liner isnt going to be cheap :-(

[Dave Liquorice]

I don't think sealed per se prevents the use of a neutraliser but the combi does as you have no stored hotwater, thus nowhere to dump the heat from the boiler when there is no demand. Combis, 'orrible things no power = no hot water or CH and a failed water supply = no water.

You don't want the pump, the power goes, no circulation in log burners boiler, it boils (may explode or suffer damage), to prevent that you have to shut the log burner down sharpish just when you want it as your backup heat source...

The loop from boiler to upper heat sink (rad or cylinder) needs to be free flowing without pumps or valves. You could pump another loop down to the lower rad though.

22mm vent and 15mm feed are probably easier than a 28mm gravity loop from the boiler to the upper rad.

Yep, but I'm not expert on what the regs say is required. Have a dig about the web.

[AJH]

I'm not sure of the legal position but think you can open the fireplace and then use it as an open solid fuel fire. Once you install a logburner that is used "shut" (and is below 50kW(t)) then you should conform with part J. This means the flue must also comply and if it's the original then I don't see how you can show it complies. So a 150mm minimum diameter liner (and it can be metal or other construction) will be necessary. Even if you go guerrilla there are good reasons for not venting a 150mm wood burner flue into a 220mm masonry chimney, principally to do with loss of flue gas velocity and heat. I actually came across a gas fired AGA that had been flued directly into a brick chimney and it simply never heated the chimney up enough to draw, couple this with a centrally heated house and a higher, adjacent chimney which was also open to the living space and you may understand why there was a draught into the house from the AGA air inlet, the householder didn't and wanted nearby trees felled to "solve" the problem, on advice from the installer.

You will need adequate air provision also if it is above 5kW(t)

Plumbing this in will cost more than the boiler won't it? Both of my wood burners are space heaters and a gas boiler does the hot water and the one radiator we use, ch system being here when we moved in and it has never warranted the expense of a wood burning boiler.

Yes it must have a gravity feed and a vent direct from the boiler to the F&E tank but this I cannot see how this precludes running it with the sealed system with a heat exchanger and a thermal store. In fact thermal stores make sense with a batch loaded wood burner if you have the space.

AJH

[The Natural Philosopher]

Youu would be daft not to totally reline. With a double insulated flue at that. Keeps the flue inner hot and the soot down. Stoves can burn mega hot. Much hotter than an open fire.

I think you can use a closed system..not sure. There are pressure issues if the thing boils..so its not trivial, but with appropiate safety systems in place it should be no worse that a pressurised hpot water system

You can certainly use a pumped system, and probably get up to about

5-10KW total stove output. enough for a well insulated house.

The only downside of solid fuel is the massively labour intensive nature of it. Its the day when you are in bed with a cold feeling like a eunuchs limp dick, that the wood runs out, and the ash needs clearing..etc.

My wifes parents used to have a house with only a coal aga, and open fires to heat..clammy bedclothes, up at 8 a.m. cos its too cold to stay in bed..downstairs, bank up the aga with two scuttelfuls of coal, fetched from an icy bunker..clear the ash and clinker, then collect some kindling, split some logs and build a fire..9 am. almost time to have breakfast. Forget a shower, There isn't one. Forget a bath, or there will be no hot water for the next 3 hours..

So do I, but I don't miss the hard work that goes with it. We have two here and a stove. We light one when its really cold, mostly the CH takes the strain tho.

[The Natural Philosopher]

Oh yes.. the old house here used to have such a system. Never worked out how it worked tho. It wasn't SEALED tho. At the least you should be able to kook up a gravity fed heat exchanger and preheat the water to the CH system.

[The Natural Philosopher]

? ? ? ? ? ? [e-mail]

? ? ? ? pam is missing e-mail

About a grand. With fitting. That sort of order,

[Steve Firth]

Uh humm, are they *your* large woods? If so then by all means take the wood, if not then you're stealing.

[Staffbull]

They have days during the year they allow locals to collect fallen wood, keeps their woods clear for free i suppose, goes back many generations and is an old piece of local law if you like, the family that own the estate date back and are related to Prince Llewelyn the last "real" prince of Wales.

[mail]

See this

[Anna Kettle]

chimney before a stove is put in. I have friends who have a big old chimney very similar to mine, they didnt line their chimney and it works perfectly well with a woodburner

Anna ~ ~ Anna Kettle, Suffolk, England |""""| ~ Lime plaster repair and conservation / ^^ \ // Freehand modelling in lime: overmantles, pargeting etc |____|

[The Natural Philosopher]

It certainly is if its a new flue, I was made to line mine.

Where does it say there that you do not need one?

It also does not mention flue heights above thatch either. Thats a fairly crucial part of 'safe practice' for thatch.

I suspect that in the end its down to the BCO in an old house. If the flue is ceramic lined and in good shape he may let you use it.

However being as two of our neighbours are voluntary firemen, the number of fires started from solid fuel in bad stacks is an extremely large part of their duties..and having had sister in laws house burn down due to unsafe operation of an unattended wood fire..I am inclined to think that a proper liner if there is ANY doubt, is something I would do automatically.

I've set chimneys alight on more than one occasion too. Is your brickwork capable of sustaining a red heat..how much timber is in contact with it ?

No. double skinned insulated stainless steel flues. I am not interested in what you *might* get away with legally.

;-)

[andrew heggie]

That's right but the difficulty arises in proving that the existing chimney meets regs without a liner, so an installer would be unsure to sign off a flue installation plate.

As did many chimneys before the new regs came in in 2000.

I fitted my wood burner (small Jotul) 30 years ago and it vents, via a short 150mm enameled steel flue into a 220mm concrete lined chimney and works fine. Doing the same job now I would probably opt for a 904 stainless 150mm liner with vermiculite insulation.

AJH

[Anna Kettle]

Nowhere. But equally it doesnt say that you do need one

It mentions height above combustible surfaces like thatch in the 'flue outlet heights' section

There are regular pictures of such cases in the Bury Free Press, but every single one I have seen has been in a house with a thatched roof which makes me extremely suspicious that the problem is not with the flue but with sparks shooting out the top, in which case a chimney with a liner could be worse than one without

So I'd like to know just what do your firemen mean by _bad stacks_?

But was that anything to do with the flue????

Go on ... convince me! I'm interested in this cos I shall be putting a woodburner in myself next summer and I dont want to do any unnecessary work but on the other hand I dont want to be left with a dangerous system either

It sustained a red heat when the bricks were made so I suppose so

Some ...

hmmm. You might be right ... but then you might have just fallen for the hype :-)

Anna ~ ~ Anna Kettle, Suffolk, England |""""| ~ Lime plaster repair and conservation / ^^ \ // Freehand modelling in lime: overmantles, pargeting etc |____|

[Anna Kettle]

I shall be installing it myself so I dont care about that

You are another person who would go for the insulated liner then ...

Anna ~ ~ Anna Kettle, Suffolk, England |""""| ~ Lime plaster repair and conservation / ^^ \ // Freehand modelling in lime: overmantles, pargeting etc |____|

[andrew heggie]

For preference, yes and to get the flue signed off yes also. There can be efficiency improvements as it means you can reject flue gas at a lower temperature and still have an effective chimney, but the woodburner would need to be designed with this in mind. In fact there are all sorts of reasons why an insulated flue of the correct cross section is better, the only drawback is that the flue tends to cost far more than the wood burner.

Some types of woodburner, masonry stoves, actually use a massive fireplace to absorb heat and then release it into the room slowly, these burn at a very high power and wouldn't work with an insulated flue as they depend on the flue passage as a heat exchanger, a bit like roman hypercausts.

AJH

[Pete C]

Hi,

Soot buildup could be much more of a problem with unlined chimneys.

So for professional installers, lined insulated chimneys have much more butt covering potential in case the chimney gets neglected.

Once a chimney fire gets going I wonder if it's easier to stop with a stove rather than an open fire.

Maybe worth getting the opinion of an experienced chimney sweep, who may favour something that needs more sweeping, but could have some good advice.

cheers, Pete.