De-ashing an anthracite core in a Rayburn 355M range.

Firebox immediately prior to a full de-ash. Core is well down inside the box.
Core in the firebox after all ash and small items removed by agitating grate bars and raking the core from the top. Core is well reduced.
Product of the full de-ash in the ash pan – contents include product of partial de-ashes carried out since the previous full de-ash, ie is the full amount of ‘ash’ shaken out over 24 hours, though the bulk of the content is from the full de-ash. There was a considerable red glow in the top-centre of the content, when the photograph was taken, though this can barely be seen in picture. If the ash had been smoothed out and a slab of meat thrown on top of the middle of it (not recommended), the meat would have started sizzling at once.
Full content of ash pan now in ¼” (quarter-inch) riddle. If not shaken quickly, riddle can become too hot to touch.
Remaining content after the riddle was shaken. Most of this is burnable fuel.
Same content, having been transferred to ash pan. This content is shaken, from the ash pan, back into the firebox on top of new, raw fuel, but not at the very top; there should be a layer of new fuel added above it.
Close-up of content which has passed through the ¼” riddle. As can be seen, a ¼” mesh is probably not fine enough, as there are plenty of black specs of burnable fuel.
The refilled firebox, telltale smoke indicating the weight of the fresh fuel has not crushed the shaken core from the previous firing (see second picture above) into submission. If full de-ashing is carried out on an overly reduced core, the remants left after shaking the grate and raking the fuel will probably go out of their own accord or, if they continue to glow but are too few, the new fuel will crush and smother them. In this picture, the fuel salvaged from riddling lies just below the virgin coals at the top.
The same core an hour or two later, fire having spread throughout it (though the top side of the topmost coals never lights).
Same core as immediately above, but without flash – this can be compared with the first two images in this series.

All pictures taken during the evening of 19th April 2012, in Ireland. It is possible that a full de-ash can be left for as long as 48 hours, depending on the intensity of the heat required. Partial de-ashing is carried out by gently poking the underside of the core, to tease readily freed ash into the ash pan’s compartment, but without disturbing the lie of the core. If disturbed, the core’s contents will compress, stifling the air flow. During a full de-ash, such compacting is obviated by the action of raking from the top, mentioned above. The raking throws the coals around, causing them to settle loosely. Partial de-ashing reinvigorates the anthracite fire, but does not dislodge ash trapped higher up. If partial de-ashing, only, is carried out for too long, the fire will start to deteriorate.


About William Lambton

No news is good news.
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1 Response to De-ashing an anthracite core in a Rayburn 355M range.

  1. The above article is a little out of date and will be revised in due course!

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