joemillonare

Hi Bill I have been reading your replys with interest I posted a question for you a while back number 65 but have not had any response any advice please.
from Joe

We have an open fire with 2 glass doors on the front. With a traditional concrete round sectional chimney. The problem is a real fire tends to burn a lot of wood I am not sure of the figures but about 80% of the heat seems to go up the chimney and about 20% comes into the room with this in mind and being currently in the uk and have purchased a firefox 8 multifuel wood burning stove from Stoves Are Us. To bring back with us in Jan/feb (we drive back in our van). included with the fire was a 1 meter length of black tubeing and a throat plate (what ever that is). Am I correct in thinking that the new fire with the new black pipe only has to reach into the existing concrete chimney and be sealed off at the joint between the two different size diameter pipe/chimney sizes or does the new 7 inch black pipe have to extend right through the existing chimney to the top.

warren d

Yes I tried that but the kettle melted because it was one of those plastic electric kettles.

bil

Sorry Joe, I must have missed this.

Quite right, an open fire will eat wood and vent heat into the great outdoors. Worse, when it's not in use, it will still throw warm air away all day.

It's difficult to comment on your setup with the glass doors, but if it is burning a huge amount of wood, my guess would be that the seals around the door aren't good, and/or the air control isn't good, and this is causing the fire to burn hotter than necessary.

I never bother to try and keep the fire in overnight as that too tends to use more wood than I like, and isn't really necessary, as it's easy enought to relight it in the morning.

Leaks like that can be tested for with a joss stick or cigarette if you are that way inclined.

The pipe does not have to extend throughout the whole flue, but you will need to make a good seal between the enamel tube and the existing flue. This isn't easy, and is always the weak point in any of these installations.

Mitzyboy

A new seal is not a lot a money. Ours needs replacing, and you can tell because the glass door is blackening up very quickly.

bil

That's true, but the seal needed in the flue, while not too expensive is such a pig to do, let alone do well.

If the glass blacks, it usually means that the fire is not burning cleanly, and can mean that the flue is partially blocked. In some models of stoves they use an airwash system that directs a blade of air up the face of the glass, and if that becomes blocked it can cause blackening.

Be very careful re cleaning the glass, as if you scratch it, then cleaning it will become progessively more difficult.

It's surprising how abrasive some things can be. Those plastic scourers for example will effortlessly scratch stainless steel, so I wouldn't recommend using them.

If you replace the seal around the door, you will need to shut the door to hold the seal in place while it sets. Use a layer of clingfilm or something between the door and the frame when you shut it or the glue might stick the seal to the stove body as well as the door and then you will risk ruining it when you force the door open.

campolife

I know there was a previous thread detailing, as much as possible, the costs of running a wood burner for say 10 hours a day. Having done a search I have failed to find it again.

So does anyone know about costs?
I have seen ads for wood delivered at 9c per kilo. Is this typical?
How much wood is used in an averagely efficient burner?

Or are there too many variables here?

fionamw

I'll be interested to see how/if bil answers the questions about how much wood is used for a 10 hour day; I'd have thought that depends on whether you keep it just ticking over or roaring, whether the fire has multiple controls or none, etc.
Ref cost, that too must depend. Prices here are 11-14c/kg delivered (& by my 14c chap, stacked in more than one location, very neatly too!), mixed olive/eucalyptus/oak.

bil

Sorry, just too many variables. Off the top of my head, it depends on the quality of the stove, the efficiency of the stove's seals, the density of the wood and above all, how dry it is.

Then there's the other variables. How the house is constructed, the height of the ceilings, the degree to which the room is ventilated, how cold a day it is and so on.

I tend to look at the cost of a winter's wood. This year we paid 300 euros for three stacks worth in our woodshed. That should last a season, but we will be better placed to say when I can see what's left after the winter.

lic

Hope this is not too off topic.

In your opinion how much would it cost to have a chimney relined, or a flue fitted?

Thanks in advance.

bil

N.P.I.

Sorry, not a clue. In the UK using flex twinwall, I'd guess at 1 - 2K depending on access.

charleyfarley1

Hi All, I will revive and update you on this post. Went back to the shop and explained the fault, seems the installer was bodging work all over and is no longer employed. Thanks to previous posters for finding spanish web pages with detailed instructions. New guy has inspected job and agrees that it's all the wrong way round but due to bad weather still waiting for him to do the work. I decided to start banging out the refractario mortar mixed with bit's of old block around where the pipe exits the house wall, no easy task. Got me to thinking that it really should have some other kind of heat resistant material like what Bil has mentioned in previous posts. Bil can you recommend where I can get such material, name in Spanish perhaps. I know with my experience here in Spain trying to find such things is difficult at the best of times. Really would like to get it installed reasonably correctly now! oh and also can the pipes to be dismantled be used again if they can be parted from the sealant?
Thanks for your help.

bil

Glad to hear you have got some kosher advice there. I'm sorry but I don't know the spanish name for the insulation you need. Google vermiculite or perlite, shove it thru a translation page and start asking questions at various shops. The phrase I would carefully translate would be 'granular/particulate material that is heatproof to insulate a hot pipe.' Pictures of the material would also help.

If the pipes are carefully removed, then I see no reason why they should not be re used, altho bear in mind I can't see them to verify it 100%. Throw away any that are obviously corroded or weakened, as it's a false economy to reuse those.

billgates

Can I ask a question about this statement bil?

If the male drops down into the female and the smoke goes up the pipe, isn't there a risk of smoke escaping through the joint?
Why wouldn't you have the male going up into the female ? That way the smoke would have to double-back on itself to come back down through the pipe joint?

The reason I ask is that I originally fitted my pipe with the male dropping down into the female, like you advise, but when the fire roared I occasionally had smoke escaping through the joints. Having just moved our woodburner I decided to fit the pipe the other way round. Have I got it all wrong and should I now fit the pipe in the same way I originally had it?

Cheers,
Bill

twistedmelon

.....I have not been reading all this thread but I too thought this pipe set up strange.
All the fires I have seen here have a male outlet therefore there is no option but to do it the opposite to bil's way. I looked everywhere for a fire with a female outlet or an adaptor to change the outlet but could not find one.
I used sealant and have never had a problem.

bil

bil's way is the right one. Look in Building regs Approved document J if you want to check.

If smoke comes out of a joint then something in the flue above that joint is causing back pressure.

Do bear in mind that I have had 30 years in this trade. The point is that the biggest problem is condensate, which can occur in the best designed chimneys. You MUST build the flue/chimney to prevent its leaking out because if not, it will make the appliance unuseable.

If smoke comes out get it swept, as that is the best way of identifying problems if they can't be cleared by sweeping.

As for the male joint on the top of the stove. Yeah. Dumb, ain't it? Not all appliances have it, but an awful lot do. Usually, the flue pipe is so hot at that point that condensate isn't a problem, but yeah, I'd use a heat proof sealent on that joint and keep my fingers crossed. Consider this, I have been commenting on this very problem for 30 years, but hey, who listens to a chimney sweep? I have been told to ***** off and mind my own business by an impressive range of people. Architects, builders installers and designers, all of whom were too retarded to grasp some of the most basic concepts in flue and chimney design.

The alternative to that dumbass problem is to make an adaptor that goes from female at the top to sub-male at the bottom. It only need to be long enough to cover the two joints.

As regards never having a problem. You forgot an important word. YET.

You have not had a problem YET. I'm not taking the p*ss here, you could go on with that setup for 20 years and not have a problem. Equally, tomorrow.....

Bear in mind I dealt with chimneys by the thousand every year. That means if there was a 1 in a hundred chance of it happening, I would see quite a few.