"Asking for a friend": my mate has a woodstove which has "a stainless steel flue which is on an outside wall" (his description). He has read that this can mean that the flue can get very cold, resulting in a down-pressure, making the fire difficult to light and getting up to speed. His house, by the way, is one storey, hence a pretty short flue.
I suggested that perhaps burning a sheet or two of newspaper on top of the prepared fire-to-be-lit might whoosh the cold air upwards and overcome the problem, but he doesn't think so.
He's keen on the idea of a chimney flue fan:
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[astonishingly expensive!] and he'd like to know if anyone here has tried such a fan?
I don't, and can understand the problem, as my woodburner sometimes "chokes" on the smoke trapped by cold air in the flue/chimney, even though I use a lot of paper and kindling to get the fire going. I've never tried it, but I have wondered about a hair drier or fan heater placed to blow hot air up the flue for a minute or two, just to lift the cold air out the top of the flue before lighting the fire. It might be worth trying just to see if it helps.
I once had a problem caused by the suction of an extractor fan making the fire hard to get going. The house was pretty draught-proof. Switching the fan off until the fire overcame the suction cured the problem.
I spent a lot of time shopping around for a flue fan, many are very silly prices but sensibly priced ones can be found. I bought mine from a supplier in Italy - Gemi Elettronica. It cost £257 in 2021.
It is very, very useful. We have a wood burner which has a shorter flue than it really needs (mostly due to not wanting it visible from the road) and with some wind directions the fan is a real boon. It also makes lighting the fire a whole lot easier.
Youtube will have plenty of examples of "heroic combustion". Involving BBQ briquettes and liquid oxygen.
On a stove, you adjust the draft-sliders, according to the stage of the burn (open to start, closed down when you go to bed).
In a room with a stove, you can "crack a window a notch" to guarantee draft air, but in the average leaky house, it does not seem to make a lot of difference to a draft problem.
When you run multiple combustion devices in a house, and one of them has an inducer, it affects the draft (and operation) of other passive combustion devices. You have to review your fleet, and see if all devices will need their own draft inducers. You may notice for example, that exhaust fumes are being drawn backwards, through the other passively operated combustion devices. Using the inducer on your stove, could have consequences.
It's generally recommended, if one device has an inducer, and you own a second device, that it be switched over to inducer as well. The devices may have a "flap" that is a one-way device preventing movement of air backwards. That's to help prevent exhaust air from being drawn backwards through combustion appliances.
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Does the install meet the height-above-roof recommendation ? Maybe the thing will have enough pipe for draw, if meeting some sort of recommendations for install. Presumably there's some reason for these rules. Not that this guide has a lot of rules.
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If your proposed draft-inducer, sits on too short a length of chimney pipe, perhaps the exhaust gas temperature will be too hot for the motor. Draft inducer motors use oil-less bearings (like a bronze bearing), and the motor may be impedance protected (so a rotor stall does not cause a thermal event). Impedance protected motors do not normally have all the best torque. This means your expensive fan, Will not have the pressure differential of a Henry.
Friends of mine had a wood stove with similar problems but only in the coldest of weather and when the stove had been unused for more than a few days.
The trick to getting the fire drawing was to use firelighters to light the kindling. They kept burning long enough to provide enough heat to reverse he flow in the flue. Then, once the fire was started opening up the stove so that the fire burned fiercely for the first log or two.
This method of lighting was only required if the flue had got very cold. The fire lit with some newspaper, kindling and a match at all other times
Logs make very little, if any, ash unless they're very dirty. They should burn just about completely. We burn home grown logs and I only need to empty the ash every two or three days and that's probably because the logs aren't particularly clean. When we burn smokeless fuel we get *much* more ash, needs emptying daily.
In general newspaper doesn't make much ash, it's more expensive paper with lots of clay in it that makes ash, cardboard (as in Amazon delivery boxes) is quite good for fire lighting too.
I've noticed more ash with the beech we burnt this year than with the cypress burnt in previous years. According to
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there is about 20% more. In any case, the total is around 1% of the dry weight of the wood. It just looks more as the density is so low compared to the wood it comes from.
Interesting, a lot of our home grown wood is Leylandii so, presumably, much like cypress. Yes, what ash there is from wood is light and fluffy isn't it.
You put newspaper in a sink. Add water and a bit of dish soap (fairy liquid). Soak for one hour (the paper needs to keep its integrity so you cannot soak for too long). Remove news paper, and hand roll a small stack of the paper, into a log. Take outside and dry in the sun. The liquid part of the operation, is so the "log" will assume a shape, without any fasteners around it. If rolled tightly, that helps the "log" to burn slower.
These used to be sold in petrol stations, as some company made those as an "instant festive fire for the fireplace". The fad lasted about five years, before disappearing. It went the way of hula hoops, as the number of citizens with fire places, wasn't large enough, or the people rich enough, to afford those "logs". The logs were not cheap enough, to be cheerful.
Today, newspapers are too thin, too lacking in materials, to make good logs that way. There's not even enough newsprint to wrap fish guts any more.
And I see someone has made a machine to press out newsprint "bricks". Rather than roll the wet newspaper, it can be compressed into a brick you can burn. That just doesn't seem as "festive" as a round log meant to emulate firewood.
(The work of seriously disturbed individuals :-) Everyone needs a hobby. )
I remember reading the original article by Dave Barry
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recounting the efforts of a university professor called George Goble, in which he said the geeks being geeks, they tried various methods ranging from oily rags, through propane torch, paraffin and petrol, to liquid oxygen. And somewhere along the way, the problem shifted from how to light the barbecue so they could eat, into how to make the most impressive fireball. "Fanaticism consists in redoubling your effort when you have forgotten your aim." (George Santayana).
The article said that the LOX caused the barbecue to collapse in a heap of twisted metal, and they concluded that it was substandard, as opposed to concluding that it wasn't designed for the temperatures reached when barbecue charcoal is burned so rapidly with the aid of LOX.
That brings back memories, probably in the late 70s or early 80s, of my dad trying to make newspaper bricks in a little mould that compressed the paper-and-water pulp to extract as much water as possible.
The bricks took so long to dry, even after squeezing out as much water as humanly possible using the lever-press, that the water and paper started to smell vile, even if the "logs" were left outside in the sun to dry as fast as possible.
Mum banned the logs from the fire, because the whole living room stank of smelly, putrid newspaper.
Looking at what you have written, I think his mistake was to leave the paper soaking in water for way too long (several days...) so it went pulpy and *lost* its integrity, in an attempt to make it compress well, rather than the wet sheets (as opposed to pulp) coming apart as soon as the pressure was released. He probably left it soaking for so long that mould started to grow...
At the moment we are burning a mixture of birch and oak logs on our stove (*). But we also use compressed-sawdust bricks to start the fire and get a good base, and peat bricks to keep the fire in for a long time if we need to leave it unattended when we go out. The ash fills the ash-pan of the stove after about three days. I'm not sure how much of the ash is due to the wood and how much to the sawdust bricks and the peat bricks.
(*) In the past we've managed with pruned branches from cedar trees and with branches/trunks from fallen willow trees, but we used up all our supply from the initial work we did on the garden when we moved in, and the dead trees that blew down in gales. After the most recent fallen tree (a multi-trunked coppiced willow which split apart at the coppice), I have a lot of logs cut up, but they will need another year of seasoning and then a year to dry out under cover, before they are ready for burning. Hence the need to buy in a couple of pallets of logs until ours are ready.
I've never had much success with newspaper, because it burns away before it has properly lit the kindling which in turn needs to light the logs.
I stand two sawdust bricks (about the size of house bricks) about 5 cm apart on the grate. I put a firelighter (wood shavings soaked in wax and "woven" into a cylinder - not sure where we buy them, but they light very easily and stay alight for a long time) in between the bricks, with a few sticks of kindling wood on top. I then put a brick lengthways above this, above the firelighter and kindling, and put a couple of logs on top of that.
I find that birch lights more easily than oak from the kindling, but oak burns longer and hotter once there is a good base.
Birch bark is the secret there. It burns well, compared to the woody part underneath. You could use birch bark as a tinder, and just leave the birch sticks sitting on the ground.
And some kinds of wood, are too expensive to burn :-)
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