Getting a better draw

[rerick]

I have a Harman p61-2 stove. I had some earlier issues with venting in that I was using too many elbows and only 3 inch pipe. Well I now have coming out of the back of the stove the following. A tee to a 90 and straight out 2 feet to a termination cap. Now the stove runs much better but the draw is lousy and I would like to make it better. I know its lousy because when I shut the stove down to clean it and take it apart I can feel the air being suck in. So I feel the stove is working harder to get the air out because it gets lazy when the ash builds up an inch or two and from what I have been led to believe that should not be. I am considering outside air but if that won't cure it I would hate to cut another whole just for the sake of a guess. What I was thinking was 4 inch out of the stove and converting to 6 or 8 inch pipe and going up about 10 feet which would be about 3 feet about the back roof line. The photos show what I had and what I changed to. Basically I would go up the side like the photo shows only in a larger pipe

 

[rerick]

What I have now.

 

[lessoil]

We also have the P61 and had it installed like you have now.
As far as the lazy burn goes, I have my combustion fan maxed
out to try to better burn the high ash pellets we have.
We run it in Room Temp mode and feed rate of 3.
It is working well!
I could post a picture of our install if you like.
The dealer did our install.

**Having the vertical section helps your draft when you lose power**

 

[rerick]

I have the fan maxed out as well. Funny though because it came adjusted like that when I got the stove. Does yours get lazy when the ash starts to cover the small holes in the burn pot ? That is what happens to me otherwise it burns OK I also run mine on 3 and in room temp mode.

 

[lessoil]

Yes it does burn on the lazy side when the ash builds up.
But a quick wipe with the "special" tool puts it back to "normal"
When I clean the burn pot, I use a mirror and light to check for plugged holes.
So far, have not had one plug.
One more thing, with the igniter cover off tapping will knock most of
the ash down. I have found that there is a huge amount that builds up
in the pocket below and to the back of the igniter.
A Shop Vac takes care of that.

 

[GVA]

with that venting config you don't need natural draw except during power failure...
if you have the comb blower maxed out you shouldn't have any ash built up on the lip......
If you leave it like that you will need outside air due to the proximity to the window...

original post https://www.hearth.com/talk/threads/30944/

I still think you have an airflow problem....
Either
stove still needs some cleaning
intake flapper not opening
combustion blower weak... *******EDIT******* I should add the house could be tight


Venting, the back to back 90* are most of the restriction

 

[rerick]

I am thinking the house is tight also and I will do what I have to to correct the problem because I think that the little bit of ash on the lip that forms and makes the stove run lousy and for me to have to brush it off every few hours is nuts. I am willing to add outside air if I need to but how can you tell if you need to ? I just cleaned it and it runs good for a week or so and then its back to pushing the ash off the lip to get the air flow going better.I checked the flapper and it is open when the stove is running. I too think that there is a problem with the blower motor as well. Again I called Harman and they are suppose to have the area rep call me. But I won't hold my breath waiting for that because they seem to know only one thing " Call your dealer " or " Call an authorized dealer ". The problem with that is the guy went out of business and every Harmon dealer in my area flat out refuses to service my stove. And Harman says they can't force them to do anything . [size=4[b]]HARMAN , YOUR SYSTEM OF DEALERS SUCKS AND SO DOES YOUR CUSTOMER SERVICE AND YOU NEED TO FIX IT ! [/b][/size]

 

[kinsmanstoves]

Not poke fun but it is spelled HARMAN. I am not an English major but spell the brand correctly.

Eric

 

[rerick]

That's very helpful Thanks

 

[MCPO]

I have a Harman p61-2 stove. I had some earlier issues with venting in that I was using too many elbows and only 3 inch pipe. Well I now have coming out of the back of the stove the following. A tee to a 90 and straight out 2 feet to a termination cap. Now the stove runs much better but the draw is lousy and I would like to make it better. I know its lousy because when I shut the stove down to clean it and take it apart I can feel the air being suck in. So I feel the stove is working harder to get the air out because it gets lazy when the ash builds up an inch or two and from what I have been led to believe that should not be. I am considering outside air but if that won't cure it I would hate to cut another whole just for the sake of a guess. What I was thinking was 4 inch out of the stove and converting to 6 or 8 inch pipe and going up about 10 feet which would be about 3 feet about the back roof line. The photos show what I had and what I changed to. Basically I would go up the side like the photo shows only in a larger pipe

When you say you can hear the air being sucked in, is that air coming into the stove from the vent itself or air rushing into the stove from the room and out the vent?
If air is coming in from the vent it would be a real concern and mean your house is pressurized.
. Air rushing out the vent pipe would indicate a favorable draft.

 

[rerick]

I can feel it coming in through the vent from outside the house

 

[MCPO]

I can feel it coming in through the vent from outside the house

OK, forgive me for what might have been too quick of an assumption on my part regarding a real concern on air coming in from the vent pipe while cleaning.
Sure, It could very well mean the house is pressurized and affecting the fire(lazy fire and not drawing well) but it also could probably be just a normal amount of cold air coming in with the house pressure equalized.
In any case I`d check for stove leaks and or the house pressure .

 

[rerick]

In any case I`d check for stove leaks and or the house pressure

Ok how do I do that ?

 

[MCPO]

In any case I`d check for stove leaks and or the house pressure

Ok how do I do that ?

Well, a professional analysis done with the proper guages might be beyond yours and my own capability but a quick and easy test would be to simply open a windw near the stove and see if the flame changes.
You ought to have a OAK installed directly to the stove anyway and you can test your door gasket for tightness with a dollar bill.

 

[GVA]

a magnehelic would show the draft of the stove while running
and hooked up to the stove while cold would show if the house has a negative pressure and pulling air through the exhaust from the outside...

 

[Dougsey]

I know its lousy because when I shut the stove down to clean it and take it apart I can feel the air being suck in.

I don't understand what your concern is? Open a window... doesn't the same thing happen?

Seems normal to me.