Anthrastat/Solenoid Operation

 
gregolma
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Location: Buffalo, NY

Post by gregolma » Sun. Dec. 07, 2008 11:44 pm

Matthaus wrote:I think you are confused about the effect of lowering and raising ash temp, 142 would make it ash sooner since it would drop off that temp quicker. The lower the ash temp the less it ashes. :)
I think it works the opposite.

The unit will take longer to shake if the switch is set at a higher temp. It will take the ash longer to heat up enough to trigger the switch. More time=more ashes.

I'll bet that the heat retention characteristics of the ash were calculated into this design. Ash is an insulator.

 
Matthaus
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Post by Matthaus » Mon. Dec. 08, 2008 4:13 am

The Anthrastat switch on an AA is NC meaning it will open the contacts and remove power from the ashing solenoid as the temp rises and reaches the set point. If the setpoint is lower it will have the effect of maintaining a cooler temp at the anthrastat, cooler temp is less fire more ash. The higher the temp the closer the fire is to the anthrastat. Put another way the lower the temp the deeper the ash bed the higher the temp the shallower the ash bed.

Gregloma said ash is an insulator, that is exactly right, the lower the temp the more ash will be allowed to form which correlates to less ashing. Remember that more ashing (a higher temp on the anthrastat) equals a lower fire which puts more heat at the anthrastat.

If you still don't follow my logic, wait for your boiler to be running and ashing, using an allen wrench lower the set point on the Anthrastat, it will shut off the ashing solenoid if you go low enough. :)

Attachments

anthrastat.gif

AA Manual Excerpt

.GIF | 119.5KB | anthrastat.gif


 
gregolma
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Location: Buffalo, NY

Post by gregolma » Mon. Dec. 08, 2008 2:03 pm

Yeah, that's what I meant. It was late and I was thinking of the Anthrastat open circuit backwards.

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