D'Oh...the 'ol Mansfield reached a new high temp last night

[mikeathens]

I fell asleep on the couch last night, and the wife comes down at midnight because she can't sleep - it's too hot in the house. Checks the temperature on the stove, and it's a 675 on the surface. She closed the air control all the way, and it was another 1/2 hour before the temp came back down below 600. I guess one draw back on soapstone is having the worry about this sort of thing. I never even batted an eye when my dutchwest hit 700+. I can't imagine any damage was done, but I'm going to check for cracks when I get home this evening. I wonder why Hearthstone set the magic number at 600?

 

[Highbeam]

Is the redline on that stove 600? I think 75 degrees over is probably not that big of a deal, especially if you got there slowly so that the stone was pretty much always the same temp throughout. I think the best way to crack stones is to fill the cold stove with kindling and rapidly heat the stove to overtemps.

Don't forget to check for warped or cracked castings too. Might as well check it out.

Oh, and congratulations on getting the stove hot. It means that your setup, wood, and methods are working properly.

 

[Backwoods Savage]

I've always wondered why Hearthstone has 600 as maximum when Woodstock is 700. Both are soapstone! Our stove goes to 600-650 very often in the winter. Had 680 once in the last week and that is as high as we've ever hit. Felt good too!

 

[Vic99]

When I visited the Woodstock factory last week, this sort of came up . . . . when I made reference to overfiring temps between Hearthstone (most models 600 F)& Woodstock (700 F), the tour guide mentioned that Woodstock stoves have a double layer of soapstone, I think 3/4 of an inch and 1 1/8 inch with a ~1/8 inch gap between the two. He mentioned that if the inside stone cracked, even all the way through it wouldn't be a big deal because smoke wouldn't infiltrate into the room with an intact outer stone.

Perhaps the thickness of the stone(s) has something to do with it as well. . . . anyone know how thick Hearthstone's soapstone is?

Also, the soapstone comes from 2 different places (and looks different too). Woodstock stone is from Quebec quarries. Hearthstone's stone is from Brazil, called Acaiaca stone. Maybe the type of soapstone makes a difference?

 

[Highbeam]

I believe that the Hearthstone stone is 1.25" and single layer. The other funny thing about woodstock temps is that the main heat supplier is that cat which sets right under the stove top and would likely provide a high temp in that one spot and a relatively cold stove everywhere else. I think that's why woodstock owners claim that they can heat their stoves to operating temp within 30 minutes or whatever short time, it's maybe just that one spot that gets hot.

Definitely a lot more thickness to the woodstock at 2" including the insulative air gap.

I ran a "stove cleaner" burn last night by filling the cold stove with small splits and running with draft at 100% for 45 minutes per the manuals directions. It was a hot fire and at the end of 45 minutes the stove top was only at 425. Even after cutting air the stove temp climbed to nearly 500 over the next 20 minutes making me think that the stone's inside was hotter than the outside during the wide open burn. Sure cleaned things up nicely and got the pipe nice and warm.

 

[Todd]

I have also inquired about overfire temps of both stoves and yes Woodstock has 2 layers of stone in the stove body, but only 1 layer on top above the cat. I was told 700 is no problem for the Woodstock as long as the fire box is not a roaring inferno and the cat is taking most of the load. They are more worried about the internal cast parts warping than the stones cracking.

Highbeam is correct, you can have a very hot top and relatively cooler stove body when the conditions are right and the cat is feeding heavily on smoke.

I think both stoves should be able to handle those overfire temps on occasion, but not on a continuous basis.

 

[FireWalker]

Ever since I started loading NS thru the front door I am having trouble keeping the stove below the high end of the "clean burn" zone on my rutland (600). Even with air completely shut, once a load is going I'm pushing 600. I can't imagine running at around 1/3 air setting. I think my thermometer is giving me higher than actual readings. This stove has also been above 600 (on my rutland)numerous times and I see no ill effects. One cold day in the future I will let a full load burn at 1/4 air setting and check my thermometer. This reading will be my new maximum temprature as this is the setting the manual says is MEDIUM LOW BURN RATE and this is the typical setting for unattended burns.

When ever I let the stove burn at this setting my wife askes "should you turn it down"?????????? and not because it's too warm, but because the fire beind the glass is burning up a storm in there.

Finally cleaned the chimney this weekend, first time since installed in September.........had about 1/2 of a 5 gallon bucket of black creasote mostly in the cap and exterior top portion of chimney, I've been keeping my eye on it all winter and until I started burning NS I didn't have a problem. I think now that the stove tends to get hotter than EW burns and we are stutting the air down completely more often thus making more creasote. Still learning, cold nights and warmer days means smaller loads with hotter air settings i.e. get the stove hot in the morning and let the stones do their magic during the rest of the day. Avoid long low burns.

 

[mikeathens]

I tend to worry about this kinda thing too much. I don't plan to repeat this, but I wonder if any damage that could have been done would be really apparent. I would hope that these companies build in a factor of safety on their "overfire" temp of say 100 degrees.

 

[Highbeam]

To see if you damaged anything I would first do the visual check for big cracks. Remove all the ash. Then start a fire with a healthy load of kindling and small splits. Point is to establish a healthy draft and plenty of gaseous fuel. Get a good secondary going and shut the primary air off. The goal is to make a big suction in the stove and provide enough fuel that a leak would be very apparent. Other than actual leaks and broken stones what could have been damaged?

 

[mikeathens]

To see if you damaged anything I would first do the visual check for big cracks. Remove all the ash. Then start a fire with a healthy load of kindling and small splits. Point is to establish a healthy draft and plenty of gaseous fuel. Get a good secondary going and shut the primary air off. The goal is to make a big suction in the stove and provide enough fuel that a leak would be very apparent. Other than actual leaks and broken stones what could have been damaged?

That's sort of what I was thinking, Highbeam. I went over every inch of the stone last night with a bright flashlight and did a visual inspection of all castings for cracks and warping. Nothing. Don't want to hit that temp again, but it looks like no big deal. Man, what a s**tload of heat that thing was putting out!