nicknorman

Coop as said, small Tesco express near Fazeley Jn. If you want mega-shopping there is Ventura, which has Markies, Asda, Sainsburys and most other things you could think of. About a mile walk north of Fazeley Jn, or slightly closer (to Sainsburys) at Bonehill Rd bridge.

How old are you? How many cells in your body are the same ones you had when you were born? And of course you are 70-something % water - but that water is constantly being excreted and replaced by new water.

Planks don't grow on trees. They grow in trees.

Some bits of Stoke are a bit grotty, I would only moor overnight above Etruria lock, at Festival park outside the pub, or preferably at Westport Lake. In Stone you can moor anywhere you can find a space, but quite a bit of it is given over to the boatyard.

Of course that is nothing to do with the fact that the entire extent of equipment on "historic boats" is no more than a coal stove and paraffin lamp, whereas modern boats are full of electrics, electronics and shore power connections. Anyway there were plenty of seriously rusty / holed historic boats around - but of course lots have recently been restored/repaired. And don't forget the woodworm!

He's phoenixed a few times, but not recently.

Oi! - equal rights for woodworm if you don't mind!

Obviously there is a lot of CO, but that doesn't mean there is zero oxygen. And obviously there isn't - it would be unreasonable to expect every molecule of oxygen to be burnt. As I said, the amount of unburnt oxygen as a %, depends on how long the oxygen is in the vicinity of the combustion which depends on the air/gas flow rate. This is why an open fire is so inefficient, a lot of air (including oxygen) is drawn up the flue, having no part in the combustion. A stove is much more efficient because far more of the air as a % is used for combustion, so less heat is carried away. If the stove has a twin walled flue then it is that little bit better because combustion can remain supported with a lower flue mass flow rate. Back to perceived vs actual, at the gliding club, the toonsers (townies, in English) who weren't used to stoves, always wanted to open the stove door since when the did that, they felt more radiant heat (if they were sitting right in front of it) and it was a constant source of argument because, as you and I know, a stove is roughly 75% efficient with the door shut, and perhaps 30% efficient with the door wide open. Although they felt the radiant heat on their faces, they were of course pulling in a lot of icy air from outside so the effect on the room temperature and thus any bit of themselves not receiving the radiant heat, was negative. But it was hard to convince them of their folly! Oh and one final point about twin wall stoves - although as we said the draw with a single walled flue on a boat is generally adequate, many stoves do smoke when you open the door, even when you do it slowly. With a twin wall flue, the draw is stronger and so the propensity to smoke when the door is opened to refuel, is less.

I think you will have seen the real world demonstration of this often, but not analysed it: You light the stove on a cold day (OK you're going to tell me you lit it in September and it didn't go out until April - but bear with me!). To get it going you have the air vents wide open. It's freezing in the boat. The fire gets going but it's still freezing. The fire is really burning up but it's still freezing. Then you shut the air vents down to tickover and suddenly it's really hot in the boat. So the point is that having a lot of draft really pulls the heat away from the stove and up the chimney. And don't imagine that all the oxygen in the air coming in the stove vent participates in combustion - most of it just goes up the chimney, pulling the heat away. So the aim is to maximise the usage of % of oxygen in the incoming air, so that for a given rate of burn the air flow (that pulls the heat out of the boat) can be minimised. With a twin walled flue, the flue gas temperature can be kept hot enough to give adequate draw without much of a flow rate. With the slower flow, more of the oxygen % is burnt and thus the mass flow of hot gas up the chimney is less as a proportion of fuel burnt - the stove is more efficient. Well I'm not sure if I have explained that adequately but the point is that neither you nor I are experts in the matter. But the experts say that a twin walled flue is more efficient and that is certainly my experience when we replaced the gliding club's old stove with single walled flue (around 4 metre high ceiling, ie long flue) with a same-sized stove with twin wall flue. Very noticeably less draughty, more heat, less fuel used. A number of club members were grumping that we'd lose room heat from the flue (just like on here!) but they all had to eat their words.

I'd have to check, but I'm fairly sure there is a maximum temperature a stove can operate at, as part of the output spec. Stove thermometers supplied with some stoves have a relatively low max temperature and the instructions advise against operating it any hotter. Of course one could fill it with hot-burning coal and get the casing glowing red (or even white!) hot to get many, many KWs, but the stove wouldn't last long. Nor the boat!

The draw with single wall flue is quite satisfactory, but that is not the issue. Twin wall flues reduce the necessary gas flow rate up the flue, and that means less icy air drawn in from outside - perhaps blowing past the occupants. In other words, improving occupant comfort. But of course the main reason why it's in the reg is the reduction in temperature of hot surfaces (the flue) that could set fire to the structure of the boat, and burn someone touching it by accident. It will also keep the pressure within the stove a bit lower, thus reducing the probability of CO leaks into the boat.

Well ok, I make an assumption about your knowledge - but based on what you say, it's a reasonable one. If you have identical caravans with identical stoves save but twin wall vs single wall flues, then the twin wall flue will require a bit less fuel to heat the van to the same temperature. If you don't agree, it because you either have differences between the caravans / stoves, or you are using anecdotal and inaccurate evidence rather than fact. You and I both agree that with a tiny stove, max heat output will be reduced with a twin wall flue, but this thread is not about your specific and unusual circumstance, it is about the vast majority of boat stoves that spend most of their time, even in the depths of winter, operating well below their rated output.

Oh the irony! You have never tried a double skin flue. Lots of people, including several in this thread, have told you that a single skin flue is best. So you believe it, and repeat the "fact" based on zero evidence. The fact is that a double skinned flue makes a stove more efficient, by reducing the mass flow rate of hot air up the chimney, and hence heat lost up the chimney. Yes I think it would be true that the maximum possible heat output from the stove/flue combination would be reduced with a double skinned flue, but it seems unlikely that many narrowboats suffers from inadequately-sized stoves that can't get a comfortable temperature when running flat out. Normally it is the opposite, the stove spends 99% of its time shut right down. Anyway I think the situation is that the standard requires a double skinned flue, but compliance with the standard is only required by a new-build RCD-compliant boat. For everyone else it is advisory. It is certainly not required by BSS.

How to stay cool? Move to the Highlands of Scotland. Around 10 degrees cooler!

I think you are out of order. Only a complete numpty would imagine that a member of this forum was, or represented, an American organisation. So there is no apparent deception and you are making a fuss about nothing. If he used the NMEA logo in a professional capacity when it was not sanctioned, that would certainly be bad, but this is just an amateur forum where some members post advice to freely help others. Don't piss on it.