Hearthstone Mansfield Air Intake...is it blocked?

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LarryDarrell

New Member
Sep 25, 2022
4
Vermont
We have a question that when we asked the dealer, we were dismissed, as though our question were foolish.

We recently acquired a Mansfield, and tried to do break-in fires, but when the front door is closed the fire goes out. The dealer says it is because there isn’t enough draft because it isn’t cold enough outside. OK, but when we put a small fan at the gap in the back, where it appears the intake for the primary air flow is located, there is no indication that any air is, in fact, reaching the firebox. The basic physics, as we understand things, would imply that the question of draft is immaterial when air is being physically forced into the system, with no need for a temperature differential to pull the air through the system.

Our concern is that this implies that there is a problem getting air from the intake port to the firebox. Whenever the dealer, either at the sales or service side, is asked why no air is getting into the firebox when the front door is closed, we are treated as though we are asking a foolish question. We were shown the parts diagrams (https://1q4gfb42pami41tumh2vps5s-wp...mansfield-iii-8013-illustrated-parts-list.pdf), but got no answers to the question, “How does air get into the firebox when the front door is closed and the Primary Air Control slide is open?” Nor does it provide any way to assess whether the air channel is blocked in any way.

This is vexing on a number of levels, and we are baffled that the manufacturer site doesn’t provide any guidance. We found the mention of an OUTSIDE AIR SUPPLY (Optional Kit #90-53220), and see the installation instructions, and interpret the existence of such an accessory to mean that there is a way to bring additional air to the system. All we were trying to do is introduce additional air by using a fan, which, as mentioned, had no effect, leading to the suspicion that there is a blockage in the system—which the service desk at the dealer assured us was impossible.

Please help. Autumn is here, and the weather is changing. We’d like to use our beautiful new stove, but suspect there is a problem.
 
How tall is your chimney? How warm was it outside?

The fan, unless tightly connected/put into the air intake will not likely get much air at all into the stove.

Outside air kits are not used to add additional air. They are meant to use not the air from your room to burn the wood, but air pipes in front outside the home.
 
Also, do you know how dry your wood is? If not, what species is it and how long has it been split (and stacked off the ground, preferably top covered)?
 
Thanks for the responses.

The chimney is fine, built in brick with a newish liner (annually cleaned), higher than the house.

The wood isn't the issue. I'm still doing the break-in burn, and just using some maple that's been in the indoor wood box since last winter.

I was still curious about the air intake. So I tried again, when the stove was cold, and found that there wasn't any turbulence when I once again forced air into (what I think is) the intake port. No ash storm or any indication that any air is being forced in, but I put my hand over the vent that the service tech showed me, and there was, in fact, air coming.

I guess that I'll just need to wait for it to get actually Vermont Cold™ outside to get enough natural draft. This is our first modern stove. Just replaced one that probably went in during a 1991 renovation, and the new one is tighter and apparently needs more patience than I seem to have.

I appreciate your help and apologize for my ignorance.
 
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On my Progress, sometimes I don't notice that the Catalytic Converter is engaged when I start a cold start fire and the fire goes out. I guess this is my way of asking - is the Catalytic bypassed when you start?
 
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Lol the trade mark ..

Maple that has been inside a year (after having dried outside) will be good indeed. I was asking as modern stoves are far less forgiving than your old 1991 stove. You can't go by what you have done for all these years. And we see a lot of "the stove is bad" when it's either the wood or the chimney.

Therefore I still think it's good to add the chimney height and approximate outside temp at the time of the issue here, especially for when (hopefully if ...) the issue appears again. The chimney is the engine of the stove and it's hard to figure out what is going on without those parameters.

Not saying you're doing anything wrong, but it's good to rule out commonly known causes for issues like this.
 
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When you say you held a fan pointed at "the gap in the back" can you share a picture of where that is?
I'm not positive, but i think the air intake hole on this stove is underneath, front left, closer to the front than the back of the stove.
 
On my Progress, sometimes I don't notice that the Catalytic Converter is engaged when I start a cold start fire and the fire goes out. I guess this is my way of asking - is the Catalytic bypassed when you start?
Valid question, indeed (no such new-fangled thing on my old stove, for sure), but I am confident that the Catalytic Converter is disengaged (the handle is spun to the counter-clockwise position).
 
I did a break in fire on my Phoenix hybrid saturday night in Northern Vt. Temps were in the high 40s. Light kindling and 1 small pc of ash log. It took over an hour to ignite and keep it flaming with draft open and ash pan door cracked. Shut down over night and burned out completely, but stone was warm to touch. I have to believe a combo of outside warm air and pressure this time of year. I would worry if it was Nov and 30 degrees outside and bad drafting, but dealer may have a point now.
 
I did a break in fire on my Phoenix hybrid saturday night in Northern Vt. Temps were in the high 40s. Light kindling and 1 small pc of ash log. It took over an hour to ignite and keep it flaming with draft open and ash pan door cracked. Shut down over night and burned out completely, but stone was warm to touch. I have to believe a combo of outside warm air and pressure this time of year. I would worry if it was Nov and 30 degrees outside and bad drafting, but dealer may have a point now.
Thanks! I'm new to these modern stoves.
 
Valid question, indeed (no such new-fangled thing on my old stove, for sure), but I am confident that the Catalytic Converter is disengaged (the handle is spun to the counter-clockwise position).
That's closed according to:
page21image1376350064
 
The (mixed?) perspective(s?) in that image make it hard for me to see how the handle is supposed to be...?
At the very least this (manual clarity) can be greatly improved...
 
How much wood are you loading in there, just a few small splits isnt enough, you need a decent base for things to let off, if you think its an air intake issue, take 5-6 crumpled pieces of newspaper (none colored) and lit those, close the door to see what happens
 
I have an Equinox I’ve used for ten years in my garage and a Mansfield I’ve used for six years in my house. When you start them up cold leave the door cracked open until you get them really going. They don’t draw much air even when wide open.If you shut the door right after starting they will die right down. Once the stove is hot the next loads take right off. They need dry wood. I burn about 9 cords a year so I’ve gotten familiar with them.
 
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We have a question that when we asked the dealer, we were dismissed, as though our question were foolish.

We recently acquired a Mansfield, and tried to do break-in fires, but when the front door is closed the fire goes out. The dealer says it is because there isn’t enough draft because it isn’t cold enough outside. OK, but when we put a small fan at the gap in the back, where it appears the intake for the primary air flow is located, there is no indication that any air is, in fact, reaching the firebox. The basic physics, as we understand things, would imply that the question of draft is immaterial when air is being physically forced into the system, with no need for a temperature differential to pull the air through the system.

Our concern is that this implies that there is a problem getting air from the intake port to the firebox. Whenever the dealer, either at the sales or service side, is asked why no air is getting into the firebox when the front door is closed, we are treated as though we are asking a foolish question. We were shown the parts diagrams (https://1q4gfb42pami41tumh2vps5s-wp...mansfield-iii-8013-illustrated-parts-list.pdf), but got no answers to the question, “How does air get into the firebox when the front door is closed and the Primary Air Control slide is open?” Nor does it provide any way to assess whether the air channel is blocked in any way.

This is vexing on a number of levels, and we are baffled that the manufacturer site doesn’t provide any guidance. We found the mention of an OUTSIDE AIR SUPPLY (Optional Kit #90-53220), and see the installation instructions, and interpret the existence of such an accessory to mean that there is a way to bring additional air to the system. All we were trying to do is introduce additional air by using a fan, which, as mentioned, had no effect, leading to the suspicion that there is a blockage in the system—which the service desk at the dealer assured us was impossible.

Please help. Autumn is here, and the weather is changing. We’d like to use our beautiful new stove, but suspect there is a problem.
The problem isn't the chimney or the wood or anything else. It's a detective design. I tried to use this stove for a winter in Colorado and I was never able to get it hot. It never gets enough air. When I open the door, fire and smoke come out, and when I close the door the fire goes out. Draft is good and tested by a professional. Wood is dry. Install is right. Look for more complaints about this stove this year as more people try to use it to heat their house. Hearthstone needs to recognize the problem and stop blaming the user. We have been heating with wood for 20+ years and this is the only stove I've had that didn't work.
 
There have been reports that some of the new Hearthstones like a stronger draft than previous models. High altitude may make this even more of an issue.
 
There have been reports that some of the new Hearthstones like a stronger draft than previous models. High altitude may make this even more of an issue.
Where are those reports? Check out the photo. My draft should have been pulling like crazy when the door was opened. Sorry to say we tried everything and the stove never worked as advertised. We really wanted to like it, but now use a Pacific energy stove that actually heats like it should. And yes the catalyst was bypassed and I opened the door slow after cracking it for a bit. This was an every time event.

Screenshot_20231007-155832.png
 
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Generally, it's not recommended to open the stove door with a lively fire but that would bother me too. I'm glad the new stove is working better for you. Which model PE replaced what model Hearthstone?
 
PE summit is new stove, Mansfield was old stove. The only way to get a lively fire was to have the door open. Closing the door resulted in vent limited, weak, smokey, smoldering fire that didn't heat up the stove.
 
PE summit is new stove, Mansfield was old stove. The only way to get a lively fire was to have the door open. Closing the door resulted in vent limited, weak, smokey, smoldering fire that didn't heat up the stove.
The Summit is a good workhorse. It should provide years of good service.