Auger Pipe Vent Holes Theory

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RICHARD2
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Post by RICHARD2 » Thu. Nov. 13, 2014 11:44 am

On what theory of operation does the pot end of the auger pipe have seven small 'vent holes' ?

When running, the blower applies positive air pressure through those holes --- which can exit at the bin end -- i.e. coal gas in the house.

When not running, chimney draft provides negative pressure over the fire pot --- which could induce air flow through the auger pipe from the bin end, and out through the fire pot if the vent holes were not present. Indeed, without the vent holes, the auger pipe would be subject to chimney draft even with the blower running -- so any 'gasses' in the auger pipe would vent through the fire bed.

In either case, preventing the fire from migrating down the auger pipe requires sufficient minimum auger operation to keep black coal in the base of the fire pot.

Hence the question, What is the theoretical basis for having the vent holes in the auger pipe?

 
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mdhorvath
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Post by mdhorvath » Thu. Nov. 13, 2014 7:00 pm

To keep smoke from backing up into your bin. Just plug them up and you will find that out.


 
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Scottscoaled
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Post by Scottscoaled » Thu. Nov. 13, 2014 9:34 pm

Coal gas will flow from more to less pressure. The air holes in the pipe pressurise the pipe with clean, fully pressurised air from the blower. The coal gas has no choice but to go out the top of the coal bed because that is where the lower pressure is.

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