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What is this knock out on the Harman pellet stove?

Post in 'The Pellet Mill - Pellet and Multifuel Stoves' started by Don2222, Aug 5, 2013.

  1. Don2222

    Don2222 Minister of Fire

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    Hello

    I am re-doing the firebox on the Harman P61-2 manual ignite stove. It will not be manual ignite much longer. LOL

    After taking the ignitorless burn pot out, I noticed this small round knock out behind the burn pot?

    Does anyone know why this knockout is there?

    Click on pic to enlarge. See yellow arrows in pic below.

    Attached Files:

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  2. ghangac

    ghangac Member

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    There are two types of Harman ignition systems. The electric fin igniter that sits under the burn pot, and a pressure ignition system that use a pressure air pump to push super heated air into the back of the burn pot through that knock out.
  3. Don2222

    Don2222 Minister of Fire

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    Interesting, I have never seen the pressure ignition system. Does it use a cartridge style ignitor?
  4. MountainSean

    MountainSean Credo Quia Absurdum

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    Here is the non fin igniter (please forgive link I am lazy this morning and don't want to dig out a picture from home)

    http://www.stove-parts-unlimited.com/Harman-450w-Tempco-Igniter-Element-p/3-20-00450.htm

    and it uses this air pump

    http://www.stove-parts-unlimited.com/Harman-Ignition-Air-Pump-p/3-20-02679.htm

    To move the air past the igniter in order to get more heat to the pellets/corn and to keep the igniter from overheating. We don't have anything showing the scale for that igniter but it is about 4-5 times the size of the fin igniters and without the air pump would cook itself to death in very short order.
  5. Don2222

    Don2222 Minister of Fire

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    Thanks MS
    Wow, 450 watts is hot! Can that light the corn without adding wood pellets on the PC-45?

    Is that for running corn on the pellet boiler and furnace?
  6. MountainSean

    MountainSean Credo Quia Absurdum

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    Yes it can light corn straight. the PC45 is designed to burn straight corn, or grass pellets, hulls etc. It has a grain cap that goes over the burn pot to help it burn more efficiently when burning those types of fuels. In order to burn wood pellets on the PC45 you are supposed to convert out the burn pot and remove the end cap.

    The larger igniter for the furnaces is because the little fin style igniter just doesn't make enough hot, which is why they changed all the furnaces over to the pressure system. The fin styles worked, but not that well and burned out a lot and had a much higher % of failed starts.
  7. Don2222

    Don2222 Minister of Fire

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    Great Info
    Thanks!

    If I put that pump and ignitor in the P61a with the Selkirk DT Pellet or Corn vent, would the grain cap fit so I could burn corn?
    The answer is no, because the burn pot weldment is different. :)
    I see
    http://www.stove-parts-unlimited.co...rch=pc45 burn pot&Search.x=-102&Search.y=-208
  8. MountainSean

    MountainSean Credo Quia Absurdum

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    No.

    That sort of modification is exactly what makes me cringe when I hear it. You cannot (or rather should not) modify one stove series to burn or use parts from another without knowing exactly what will happen. Those stoves may use a couple of similar motors but the weldment is different, the burn pot is different, the exhausting is different, and the way the pump igniter mounts is completely different.

    So, no.
  9. Don2222

    Don2222 Minister of Fire

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    Yes

    With the price of corn compared to wood pellets here in NE we may never burn corn. LOL
  10. Bioburner

    Bioburner Minister of Fire

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    The pc45 has no problem with burning and lighting corn. In addition to a different burn pot with a cap it also has a stirrer. The stove is a differant critter. Corn price went to about 8cents a pound yesterday. Will have to make room for trailer in the shed.
  11. Lousyweather

    Lousyweather Guest

    the thing is, Don's stove predates the forced air ignition by many years, so, the knockout isn't for that, although I am thinking that Don's unit is one of the latest P61's made.......earlier models didn't have it...........
  12. Don2222

    Don2222 Minister of Fire

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    I have the orig sales slip.
    This P61-2 manual stove was purchased at the Trading Post on 314 Kent Rd New Milford CT on 3-1-07 for $2500. Down near you LW. :)
  13. smwilliamson

    smwilliamson Minister of Fire

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    The watts doesn't mean hotter. A 100w igniter and a 800w igniter can get to the same temp but the higher the watts, the faster it gets there
  14. smwilliamson

    smwilliamson Minister of Fire

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    I think you guys are right about the knock out for the forced ignition. It has been around for quite a while... Or at least thought of. The p61 and the pc45 use the same stove body, yes?
  15. Lousyweather

    Lousyweather Guest

    yup
  16. smwilliamson

    smwilliamson Minister of Fire

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    There you go

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