Hearthstone Heritage operating question

[mikeathens]

I went form a Dutchwest non-cat to a heritage this past weekend. So far, I am very pleased. Very easy to operate, consistent results, and good heat.

I am a bit concerned about the possibility of overfiring this stove, more than I ever have been a cast iron. The manual states 500 F surface temp on the stove is normal, but greater than 600 F will crack the soapstones. My wife loaded the firebox last nigt when the surface was at 500. She used oak block. The surface temp climbed close to 600 F and she shut the air control completely down. This stabilized the fire, but the temp stayed at 575 F; she was pretty nervous about the temperature.

So....anyone else with this stove regularly go above 550 F? Is it more normal than the manual makes it put to be? I am wondering if I should go ahead an put the flue damper in there...doors are tight, ashpan door is tight, can't find any leaks. I'm wondering if this is just normal and not to worry about it, or is there is some unwritten rule about loading before the previous load is reduced to a bed of coals...I have a damper ready to install. Not sure if it's necessary, though...couldn't find anyhting on this on other posts.

 

[Harley]

Hi, Mike:

Actually have the same stove, which I put in this past fall. To me, it seems my stove likes the 500-525 range. with a nice medium/full load, and primary air set between 1/4 and 1/2 open, that's where mine seems to level out. I doubt you did any damage going that high, but don't think I'd like to see it getting to 575-600 too often. My guess is that didn't overfire the stove.

 

[mikeathens]

What you are saying is what I heard from the dealer - he uses the same stove. I'm just wondering if I have too much draft and should use a flue damper to cut it back a little. The manual does mention that some applications may need a damper. I have heard that it should be pretty hard to overfire these stoves with primary air at 50%. If I would have left mine at 50% last night, I'm sure I could have easily seen 700 on the surface. Anyone with the same experiences that has resorted to installing the flue damper? I never had to worry about this sort of thing with cast iron, and in fact strived for 600-700 degrees!!

 

[sstanis]

It is continual, consistent fires above 600degrees that will overfire. Key here is consistent and continual. If your stove is consistently at 600+ degrees, you run the risk of overfire

 

[mikeathens]

I don't mean to sound like Bill Clinton here, but it depends on what the definition of "continual" is...HAHA. Seriously...is it a) more than 30 minutes, b) more than an hour, c) greater than two hours, d) all of the above, or e) none of the above.

Don't even think of answering (e).

I think I have my mind made up to install that flue damper, unless someone has compelling advice...

 

[Harley]

I don't think you can really go wrong by putting in the damper... it just adds another level of control if you need it... if you find you don't need it, then you just leave it open.

 

[mikeathens]

Thanks...that's what I was thinking. I just needed a little encouragement. I don't like to modify things or unnecessarily do something unless there is a reason other than operator error.

 

[Harley]

The only drawback I can really see to the damper is just a slight amount more work in cleaning the stove pipe, and the initial installation (overall pretty much a non-issue). Again, you can always leave it open if you find later you really don't need it.

 

[MountainStoveGuy]

when i had my heratige at home, i could not get the stove above 500* if i tried. the one i had in the showroom that had a huge chimney on it i could get it to 550* if i tried real hard. I think it would be very difficult to get the stove to 600* unless your burning lumber or fatwood stumps.

 

[Todd]

I Don't have the Heritage, but I used to have the Homestead and I did get it up over 600 a few times, but it didn't stay there long. Usually tried to run it 450-550 for good heat output.

Woodstock has their overfire temps at >700. And I have hit 725 before with no damage to the stone. But this is a different animal than the Hearthstones. The catalyst is right under the top stone.

I would run your stove a couple more weeks and get familiar with it before thinking about a pipe damper. Dampers tend to cool the pipe/chimney, and make more creosote in my opinion.

 

[Corie]

Yeah the damper will probably add to slightly more creosote build up. However, if you truly feel like the draft is uncontrollable, you'll have no choice. You could of course choose my favorite draft controlling device, the barometric damper.


The reason I constantly advocate them is because they have the ability to control the draft in real time, since they are an active control. Whereas that stack damper you're going to put in, is either a set it and forget it type of thing, or its a device you'll use in emergency over draft situations only. Either way, it will not help in getting consistent and reproducible results from the stove.

Not only that, but (and I am speaking about my family in particular here) there are few members of my family that truly have the ability to recognize a strong draft and adjust the stack damper accordingly, BEFORE the stove surges to 700 deg F. The barometric takes that factor out of the equation and that's why I like them so much.

 

[DonCT]

I've run my Heritage closer to 600° before. The only reason I cut the air back was because it was starting to heat me out of my living room Hottest I've ever had it was @650°. But that was only for about 20 mins. As soon as I closed down the air, she cooled right off to around 550.

If the temps spike over 600, I wouldn't be too worried. As long and you're not running it consistantly above, no harm no foul. It might actually be good to clean some of the residue from the firebox and flue

 

[colsmith]

I have been wondering if we need a damper. Our stove burns possibly too well - our loads of wood don't last very long before they are coals, compared to the experience of others here. Even when we have the primary air control shut all the way down we can have very vigorous flames. Our manual for our Hearthstone Phoenix says that the draft should be between 0.6 and 1 wc. What the heck is a wc, and how would one measure it?

 

[Corie]

W.C is an abbreviation for Water Column or inches of water.

Without getting into pressure and its relation to velocity, the draft force is measured with a draft gauge.

And if a manufacturer is given draft specs like that, they're almost beggin for you to use a barometric! haha

 

[colsmith]

Thanks, Corie. Maybe the fireplace store could lend us a draft gauge. And actually it is fine if you want to get into "pressure and its relation to velocity." I did teach physics 10 years ago and I probably (not definitely) would still understand how it works. But I taught in a civilized country (not! --> Ecuador) where we did everything in the more rational metric system. So I am not up on measuring things in inches and what they call it.

OT water story: About 10 years ago when our water heater started leaking, we needed to get a replacement. We figured something about the size of the current one would be appropriate, but it wasn't labelled. So to most easily figure out the original water heater's capacity, I measured it in cm, calculated the volume and turned it directly into liters. Then turned it into gallons doing a rough 4 liters per gallon conversion. When talking to the water heater guy on the phone, he asked something about the existing one. I explained that it had no markings, but I had measured it and calculated the # of gallons. He asked something about the height in feet, and I had to confess I had measured it in cm. He was a little puzzled by that and said, "You must be a teacher." Why are we about the only country on the planet that still does stuff in feet and inches and gallons?

 

[Corie]

Yeah, the english system makes things soooooooooooooooooooooo difficult for us.




Pounds force, pounds mass, gravitiational constants, and of course a system is not based on a system of tens.

 

[mikeathens]

Wow, lots of interesting real-world experiences with this stove. Thanks a bunch. I love the stove and its ease of operation, but I sure don't need to ruin it by overfiring. By the way, last night, just to see what would happen, I placed my Candor surface/magnetic thermometer in the oven set at 475 F on a cookine sheet. The thermometer read 550 F. Now, I don't know if that means I can assume that the thermometer is reading 75 F higher at the range I'm interested in, or if it's innacurate when completely surrounded by hot gasses (vs. having a flow of cooler air on the gauge side, like when it's on the chimney or stove). Anyone have any thoughts? In other words, I don't know if my experiment really tells me anything. If it's off 75 F, that would mean i'm actually firing my stove to a surface temp of 525 F or so, which is acceptable.

I really studied the fire I had that was producing these temperatures, and it wasn't anything extraordinary. It was a nice, gentle lick of yellow flame with the blue propagating off of the burn tubes. Air control set at about 25%. When the thermometer read 500 F or so as I was building it up this morning, I could hold my hand within 1 inch (i.e. 2.54 cm) from the surface where the thermometer was for 15 seconds or so and not have it feel too hot.

 

[DriftWood]

Wow, lots of interesting real-world experiences with this stove. Thanks a bunch. I love the stove and its ease of operation, but I sure don't need to ruin it by overfiring. By the way, last night, just to see what would happen, I placed my Candor surface/magnetic thermometer in the oven set at 475 F on a cookine sheet.

Try the suspend in boiling water test. Boil water suspend it in the water with something. Real world physic are a blast! If its off, its the thermometer, if not your oven is to hot.

 

[slofr8]

Hi Mike,
I installed a Heritage this fall. 25' chimney straight up. Down to 10F it's fine but when it's below 0 out it's out of control. Damper closed and over 600F stove top temps. I asked here and responders suggested a flue damper which reconfirmed my thoughts. I have not installed it yet because I wanted to try and restrict the intake air. I figured this way my wife wouldn't forget to open the key with the possibility of smoke roll out. All so the creosote and cleaning issue. So far with the out side temps. below 0, when I get the stove warm for the night (about 300) I close off the rear intake by 75 or 80 percent. Then I use the front damper. This seems to work fine but still lets the top get to about 525 for periods with damper closed. As I see it, the stove was designed to run with out a flue damper but I imagine the testing does not, or can not, account for all scenarios, i.e. chimney height, pipe elbows, out side temp., elevation, I'm sure the list go's on.
Don't take my word on this. I'm only telling you what I'm trying as we have the same stove.
In the end I still may install the flue damper for peace of mind. The ones who recommended it know more about this then I do. It's just that, I hate to restrict a chimney that, at least in my mind, isn't doing anything wrong. Actually it's working exactly the way it's supposed to work. I built to have a good draft and mission accomplished.
All in all I love the performance of this stove and I think maybe most stoves in this application would have the same issues. Heck, maybe I'm getting an air leak underneath the stove and haven't been able to detect it. I don't think so but who knows.
Any way. good luck and stay warm, Dan.

 

[mikeathens]

After what I went through with my non-cat dutchwest, this stove is wonderful. I don't know if I'm burning too hot or not, but so far, I haven't seen any ill effects. I went ahead and put the flue damper in because I figured if I didn't need it, it just stays open all the time. I also didn't really have a problem putting it in because the manual actually states that some applications might need a damper. It's about 6" above my flue collar, so I don't see that it will interfere with cleaning.

A little side note: I dindn't see any significant change in the stove temperature or pipe temperature with the flue damper closed to about 45 degrees. I could hear a difference, though, in the gasses rushing past it and a difference in the sound of the air entering the inlet in the back bottom of the stove. I still had my stove top thermometer reading 600 F - another sign that it might be reading wrong.

Does anyone have a stove top thermometer that is reading accurately (like +/- 25 F)? If you do, what brand is it? I have only seen Rutland, Candor, and Lehmans available, though the last is probably just a candor with a different name on it. Also, has anyone ever seen these things deteriorate with use?

Dan, what did you use to restrict air coming in the inlet at the rear? seems like a good way to control things. I wonder if there's any danger in controlling it that way?

 

[Harley]

as far as the thermometers... I kind suspected the older Rutland I had on the previous stove (12-13 years old) was reading a little high... got a similar one, and they sit within inches of each other on the stovetop.... they have about a 50* difference between the 2 almost all of the time. I either have to get a better one, or actually do a little testing to figure out which one really reads correctly.

 

[mikeathens]

Harley, I have two Candor thermometers on the stovetop side by side. One might read 600, the other 550, but if I move them a little, the temp might change. Sometimes they read exactly the same. I wonder if there are localized "hot spots" on top of the stove?

I'm not sure if I'm going to continue to worry aobut this any more. Based on what others have said, I'm wondering if I should just shoot for 600 or less on my thermometer and let it go. It's funny that on my cast iron stoves I've had, 700 surface temp wasn't even a thought to me, but now that this one is said to be overfiring and cause damage at over 600 (with 500 recommended), I'm freaking out a bit!

 

[Harley]

I think you are right, Mike.... there probably are going to be hot spots, etc, especially around the area of the tubes, and the stage of the secondary burn. You'll probably be able fine even with those thermometers reading differently.... If the temp really starts to climb, I'm sure you'll probably hear a difference, and be able to put a stop to it quickly with the damper. It doesn't sound like the stove ever really got away from you anyway.

 

[slofr8]

Mike,
I had a piece of thin sheetmetel that I shaped with snips. I used a small C-clamp and attached it to the upper left side, looking from the back, of the intake hole.
The clamp acts like a hinge and when I swing it down it's fully open and up is about 80 percent closed. It stays down in milder temps and up when it's below 0. It's just meant as a "lets see what this will do" kind of thing and to be temporary but seems to work for now.
Dan.

 

[DonCT]

Mike, if you're grazing the 600° range, I wouldn't be too concerned. That's about the upper range of the stove, but should be damaging. HearthStone is more concerned with the stone cracking. I say as long as you've following the break in directions, the stone should be able to handle 550-600°. Like I said, I've run mine in that range during the last cold snap and it's just fine