What is this knock out on the Harman pellet stove?

[Don2222]

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.

 

[ghangac]

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.

 

[Don2222]

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.

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

 

[MountainSean]

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)

(broken link removed to 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.

 

[Don2222]

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)

(broken link removed to 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.

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?

 

[MountainSean]

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?

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.

 

[Don2222]

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.

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
(broken link removed to http://www.stove-parts-unlimited.com/SearchResults.asp?Search=pc45+burn+pot&Search.x=-102&Search.y=-208)

 

[MountainSean]

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.

 

[Don2222]

Yes

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

 

[Bioburner]

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.

 

[Lousyweather]

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...........

 

[Don2222]

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...........

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.

 

[smwilliamson]

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?

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

 

[smwilliamson]

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?

 

[Lousyweather]

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?

yup

 

[smwilliamson]

yup

There you go