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Strawberry Orange Banana Lime Leaf Slate Sky Blueberry Grape Watermelon Chocolate Marble
Strawberry Orange Banana Lime Leaf Slate Sky Blueberry Grape Watermelon Chocolate Marble


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nicknorman last won the day on July 18

nicknorman had the most liked content!

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  • Interests
    Electronics, gliding, motorbikes

Previous Fields

  • Occupation
    helicopter pilot - retired
  • Boat Name
  • Boat Location
    Fazeley Mill Marina, Tamworth

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  1. Boat came new with autochangover as standard. Advantage is that the gas never runs out - eg when it is dark, snowing or pouring with rain and blowing a hooley. Therefore not useless. If you are very poor then I suppose you may not be able to afford one. Remind me to gift you a spare candle next time I see you - I am into chariteee. Advising someone to rip it out when they already have one is not helpful. We don’t have a bowthruster.
  2. No, merely the latent heat of evaporation.
  3. The green flags change to red (or at least disappear) when the cylinder in use is empty and the device has switched to the other cylinder. The cylinder in use is pointed to by the protrusion on the white knurled ring (the left cylinder, in this case). When the flag goes red you fit a new cylinder and rotate the white knurled knob so that it is pointing at the other cylinder. A lot of people don’t like these because, if you are extremely incompetent, you can end up with both cylinder empty. However if you have any iota of organisation and discipline, you remember to check the flag every few months (or more frequently if using the gas for heating) and get a new cylinder when you find red. Not exactly rocket science, but seems to be beyond some people! As to the remaining contents of a cylinder in use, weighing it is the only reliable method.
  4. Only when significant gas is being drawn off, or has recently been.
  5. It will depend on the supply voltage. The element will be a more or less fixed resistance (R) and perhaps rated at 220v. Power dissipated by the element is V squared / R. So a 9.5% increase in supply voltage will give a 20% increase on power. Perhaps your supply is 240v? Plus of course there will be a bit of measurement inaccuracy.
  6. See my edit to previous post. I refreshed my memory and it isn’t to do with being pointy, it’s to do with relative temperatures.
  7. Interesting. Three electrodes is surely unusual? I can’t quite tell from the video but it looks like the spark is between the spark electrode and the confirmation electrode, as opposed to between the spark electrode and the burner which I would have thought would be more normal. I suppose this allows the control electronics to tell that the spark is definitely in the right place, not in the wrong place due to dodgy wiring and insulation. Normally the flame conduction detection is between a pointy electrode and the large mass of the burner, which results in differential conduction between alternate half-cycles of the ac waveform and hence the control electronics can differentiate between conduction by a genuine flame vs a soggy bit of grass or a spider bridging the gap. Edit: just reminding myself (by looking it up!) that the differential conduction -Or flame rectification as it’s known - occurs because the tip of the electrode is glowing red hot whilst the gas burner at the base of the flame remains relatively cool. Just like a heated cathode in an old glass TV valve. So reliable flame failure detection can’t work between two electrodes both bathed in the top of the flame.
  8. Surely the spark will intrinsically stop if the electrode is bathed in flame? The flame is ionised gas which is highly conductive. And the spark is also ionised gas. In other words, it is impossible to have an electrical-type spark within a flame.
  9. It only mentions coming on due to failure to ignite/burn. Having read it, it also says the electrode module should be replaced every 3 years so that might be a clue.
  10. Is it actually a thermocouple? No I think the flame supervision is by means of flame rectification - checking for the ionising (and hence conductive) presence of flame, and measuring the rectification effect due to the large burner “ground” and the pointed electrode sensor. Anyway presuming that the sensor electrode is actually bathed in flame when it is lit, and there is nothing shorting the sensor to earth, it is probably the control electronics. Unlikely to be the flow sensor as it is detecting flow to light the boiler in the first place. If the flow sensor decided there wasn’t enough water, it would just shut the flame off not light the fault light as well.
  11. Probably not. Though whether they got through the lock, or were eaten by the locals, is another matter.
  12. It just gets worse! Mind you, if one claims to be colour blind presumably one can’t be expected to obey coloured flags!
  13. Of course the other option is lithiums. More expensive and not a drop in replacement, but otherwise all the advantages you need and want. Between gel and Trojan wets I don’t think it’s a clear cut choice. Gels are I think more expensive and perhaps easier to wreck eg by over charging. If the gels are not more expensive than the Trojans, probably they aren’t very good quality. One of gel’s big advantage is tolerance of being at a funny angle - great for sailing boats but not an advantage on a canal boat. The other possibility is AGMs which I think are a bit cheaper than gels?
  14. Trojan batteries, and I expect US too as they are of a similar ilk (lead antimony), use significant water as part of their design. The correct level is just below the filler well, giving considerable margin for water usage before the plates are exposed. Other types of battery (lead calcium found in many starter-type leisure batteries) use far less water and so need less depth of electrolyte above the top of the plates.
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