Hearthstone Mansfield - Multiple issues/concerns

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pittpens24

New Member
Nov 27, 2024
20
Northwest NJ
Hey all,
I'll Start off with a few stats:
Log Home heating 1200 sq ft of floor space(with 25ft cathedral ceiling)
Burning Oak, Ash and Maple seasoned 2 years - moisture content 14-18%(18 being a piece here and there)
Temps outside lately single to double digits with negative wind chills
Brand new Hearthstone Mansfield with ash pan (professionally installed)
Brand new 6"chimney liner (professionally installed) with the stove(20 ft high off of thimble)
Coming from a Vermont Castings Defiant with catalyst purchased back in 1999, 8" masonary flue(7" square inside 20 ft highoff of thimble)
North West NJ Area

I want to start off by saying that my wife and I are not happy with this purchase and do not know if it has to do with the new liner, stove or both!

Ash Dust - The VC was a top loader where as the Hearthstone is a front loader. One would assume that the top loader would make more "dust" in the house, but that is just not true. The Mansfield is absolutely brutal to say the least! The whole house is coated in a super fine powder-like dust - It is everywhere! Even on walls, sloped ceilings, mirrors and even got into our glass kitchen cabinets!!! The VC let alot of smoke into the room when top loading. I hardly see anything coming out of the Mansfield when loading so where in the hell is all of this ash dust coming from???? This one has the optional blower which I know contributed to the issue - still not knowing how or why it would happen, but still is happening with it turned completely off. I am at a loss.

Starting fire from cold - VC was easy and awesome by opening the ash pan door to get it going. Mansfield not so great. Even with extra air from the ash pan door open, it is hard to get hardwood kindling going. By kindling, I mean kiln dried pieces from the wood shop I run so it doesn't get any better than that for starting fires. Once it is going though, the Mansfield is considerably better at retaining the coals to add wood. There is a sliding flapper on the ash pan for the Mansfield that i will be taking out at the end of the burning season. It is stupid as you need to slide it back and forth to get the ash into the pan below, but if an ember gets caught in there - then you can't shut the ash pan door until you get it un jammed - stupid design!

Heat Output - VC was amazing and ran at 1/2 throttle to 5/8 max if it was extremely cold as a general setting. Generally would go through 3 cords a year. Mansfield is totally different altogether - This thing has been running at full throttle 24/7 for the last month just to maintain 68-70 degrees in the house with the oil furnace kicking on overnight to help out once temp hits 65. The claim with this stove was it would burn much less wood and would burn much more efficiently. Normally with the VC, 3 cords would easily last into the middle/end of March. I am into my 3rd cord already with the Mansfield and will probably run out by end of next week or so. I do realize this has been an extremely cold year so there is that. What gets me is my dealer had told me that the VC was too big for my application and should have been running an VC Encore ( the next size smaller) at 3/4+ throttle for more efficiency. He also said the Mansfield would be too big and suggested the next size smaller(Heritage), however since I had to meet code, I could not have a side loader dictated by the size of my hearth bluestone. But here I am burning full throttle just to keep up. I did let it burn out completely before the extreme cold temps to check the Cats and they were clean and perfect(though they might have been clogged with ash). Again at a loss here.

Was I getting a better draft with the 7"id flue rather than the smaller 6"? I know soapstone is totally different heat then Cast iron but shouldn't it be about the same heat output once they are both at normal cranking temp? Its hard to compare apples to apples when everything has changed........
 
The real life folks I know with top loading VC say it never lets in any smoke. Maybe your draft isn't actually very strong, and the Hearthstones are more sensitive about it. Especially if kiln dried kindling won't go, it must be not enough air coming through the fire.

Do you have a probe thermometer in your flue above the stove? I installed one this year and it's been very insightful. Takes the dark art out of babying our Castleton. The stove can be hot on top, hot at the catalysts, great fire in the box - but flue temps end up way down, which kills the draft, and will cause the stove to falter within an hour if I don't adjust something.

More ash makes sense - the front door is closer to the ash bed, more likely to dust up than opening the VC's top.
 
Is the liner insulated?
Yes - or atleast the work order says it is........
The real life folks I know with top loading VC say it never lets in any smoke. Maybe your draft isn't actually very strong, and the Hearthstones are more sensitive about it. Especially if kiln dried kindling won't go, it must be not enough air coming through the fire.

Do you have a probe thermometer in your flue above the stove? I installed one this year and it's been very insightful. Takes the dark art out of babying our Castleton. The stove can be hot on top, hot at the catalysts, great fire in the box - but flue temps end up way down, which kills the draft, and will cause the stove to falter within an hour if I don't adjust something.

More ash makes sense - the front door is closer to the ash bed, more likely to dust up than opening the VC's top.
I should have worded that comment about the VC top loader a little differently - It had its moments when it would let a little smoke out, Was not a chronic thing. My point was that I could see it happening with the VC when it did, I do not notice any smoke from the HS - only if I add a piece or 2 to hot coals left in my wood bag from the night before , run out to get more and open the door to fill the stove once it is smoking.

I do not have a thermometer. Curious how one would install a probe type in an insulated double wall pipe?

Noted on the ash reference
 
You have to drill a hole in the stovepipe, which is definitely nervewracking. The probe has instructions, but you drill a small hole all the way through (outer and inner), then re-drill the outer to make the hole bigger. The probe has a little collar to close up the outer hole, and it's all held in place with a magnet.