Harman Oakwood help!

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Blstrahan

New Member
Jan 21, 2021
3
hearthPW#1
I’m beginning to think that the oakwood isn’t the stove for a newbie, but here I am. I’ve had the oakwood for almost 3 weeks now and I just have no idea if I’m getting the most out of it.

first some background, then the questions.

1. Stove is used, but dealer replaced AB, bricks, and gaskets. Stove honestly looked new when delivered.
2. Top flue approx 3 feet straight up, 90 degree out the wall and then another approx 22 feet up the side of the house. To clear a dormer 7 feet away, cap is probably 8 feet higher than roof.
3. pipe is double wall
4. Wood burned is generally ash or maple
5. I have a flue mount thermo, but from what I am reading here, it sounds like it’s useless on my setup with DW pipe.

A few questions off the top of my head:

1. From a cold start, the manual makes it seem like I should be able to close the bypass door after 10-15 minutes, but most times I stillsee smoke from the stack after 5 to 10 min. If I see smoke, I am supposed to open bypass and let coal bed accumulate. How long is too long to let the bypass open with the air control wide open (all the way to the right)? Is this when overfiring occurs? I’ve seen some posts where guys say they don’t engage AB at all. Is that bad?
2. Once I think the coal bed is sufficient and I have the bypass closed, I occasionally get puffs of smoke...accompanied by audible thuds. As I watch it, the fire dies down, I hear the stove pulling air, and I see a flash, hear the thud, see the smoke (usually from the top load door). Is draft the issue? With the height of the stack and the clearance above the dormer, the installer said I should never have draft issues.
3. Along the lines of #2 above, with air control set to anywhere between basically none and halfway, it sounds like a ton of air rushing through the stove. I’ll admit it’s scary to be in the next room over and you can hear it. Too much draft in this instance? If I dial back the air, then I get the smoke puffs/thuds.
4. Last thing (for now) - granted the thermometer I have is useless because it’s DW pipe, should I be getting 300 degree readings from it? It’s approx 18 inches above stove top. I would think DW pipe would register lower temp readings? So at 300 degrees, it’s actually way hotter than the “optimal” 300-500 degrees?

seriously, these things are finicky. I need all the help you can give!
 

defiant3

Minister of Fire
Dec 23, 2010
926
No. NH
The Oakwood has a combustion chamber (not a catalyst) much like a Resolute Acclaim. It would be worth asking the dealer what condition it's in if they looked at it at all. That back puffig often results from partially obstructed smoke path. You'll find it is, like my first wife, complicated and high maintenance. Hope the manual has something about routine cleaning of the smoke chamber? Sadly, Mona didn't come w a manual...
 

kennyp2339

Minister of Fire
Feb 16, 2014
5,971
07462
Test your firewood first to make sure its dry enough <20%, grab a cheap moisture meter, take a room temp split, re-split and then test the freshly split face.
Order a probe thermometer for your pipe, you will need to drill a hole into the dvl for this, take advantage of the hole and have your draft tested with a manometer. a normal draft is in the ball park of .05 - .08 while the fire is running at the highest setting.
Check behind the fire back (dealer should do this) there could be a clog between the fire box and the refectory that the some gets re-burned in since its a down draft stove.
Lastly - consider getting rid of the stove, Harman no longer makes wood stoves for a reason, there design has hurt the company name then helped with sales, there nice looking stoves but your certainly not the first operator to have issues with the stove.
 
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begreen

Mooderator
Staff member
Nov 18, 2005
89,761
South Puget Sound, WA
300º on double-wall stove pipe is high, but if this is with the bypass open, it's possible. Most of the heat at that point is going up the chimney. The backpuffing you are experiencing is not uncommon with this stove. It can be a challenge to run, even for seasoned woodburning veterans. If the combustion chamber is not in good condition no matter what you do, the stove operation will not be fun. And if the draft is not strong and the wood not fully seasoned, then the stove can be quite cranky.

If you do a search in this forum for Oakwood, titles only, you will find some threads with good operational tips. Here is one:
 
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Blstrahan

New Member
Jan 21, 2021
3
hearthPW#1
These responses are great! Especially the link to the existing thread on the Oakwoods, so thanks be green! In that thread I saw I saw the comments about the “jets of fire” emitting from the secondary burn chamber. When I saw these last night I was sure I did something wrong...like I overfired it or something. But it sounds like this is one of the ways you know the stove is working?

I went back through the install paperwork because i wanted to determine whether the probe thermometer was necessary since I thought it was double wall coming up from the stove. Now I wonder. The part number makes it seem like it’s single wall...so maybe the 300 degrees on a single wall pipe 18 inches above stove stop isn’t actually that high? At any rate, the probe thermometer is probably my best bet regardless. I can still use it if I determine it is single wall? Is there a way to tell that just by looking at it?

some of the other comments made about not closing damper for an hour or until that bed of coals is 3 inches thick...how on earth do you keep the temps from reaching insane levels if you burn that long wide open?

first and foremost, I don’t want to burn the house down. Wrecking the after burner and having to replace is a (very) distant second when it comes to where my worry lies. I got kids and I like them just the way they are
 

Blstrahan

New Member
Jan 21, 2021
3
hearthPW#1
Ok, confirmed with the installer that the 2 foot of flue pipe inside the house is single wall. So what is an acceptable stack temp when the damper is open vs closed?
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,642
central pa
Ok, confirmed with the installer that the 2 foot of flue pipe inside the house is single wall. So what is an acceptable stack temp when the damper is open vs closed?
Roughly 250 to 500
 

nortcan

Feeling the Heat
Sep 9, 2016
275
Quebec
That stove remind me the VC smoke path on some models, not exactly the same but near of, and on these stoves, maybe a top of the stove thermometer is more usefull than one on the stove pipe, and at least you can have both to compare ,but I would go for the on top one.
 
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Woodspliter

Member
Jan 25, 2020
131
Maine
The harmans definitely have a learning curve. I installed mine over five years ago and I'm finally getting a hang of it. Dry wood and a large bed of hot coals are key to getting a good secondary combustion. When I layer my full over night burns I start with smaller lighter species of wood and then get into the larger over nighters and then pack in some smalls to get a full load. I like mine to run 400 to 550 is ideal for me these things like to run hot. When I'm relaxing by the stove I burn a couple splits at a time in the air shut down and the bypass open