Best place to take temperature on Buck 74?

[Theonion]

I have a buck 74 insert with a blower. I've always put my thermometer on the top but recently added one to the side.
So the top thermo reads 400 but the side thermos(1 on each side) are reading 600.

Which is the better reading? The "best burn" on the thermos is 300-600 and overfire is 600+. I have a relatively small fire going right now so in the dead of winter I'm sure the sides would be 800+

 

[bholler]

I have a buck 74 insert with a blower. I've always put my thermometer on the top but recently added one to the side.
So the top thermo reads 400 but the side thermos(1 on each side) are reading 600.

Which is the better reading? The "best burn" on the thermos is 300-600 and overfire is 600+. I have a relatively small fire going right now so in the dead of winter I'm sure the sides would be 800+

First off those temp ranges sound like they are pipe thermometers not stove top thermometers. 600 is not an over fire for most stovetops. The top is probably reading lower because of the blower

 

[Theonion]

First off those temp ranges sound like they are pipe thermometers not stove top thermometers. 600 is not an over fire for most stovetops. The top is probably reading lower because of the blower

I have 2 thermometers on top of the stove and one on each vertical side around the middle

 

[bholler]

I have 2 thermometers on top of the stove and one on each vertical side around the middle

Ok but the temperature ranges you listed don't sound right for a stove thermometer. That range sounds like one meant for stove pipe

 

[Corey]

Best place to take temperature... well, I think the standards are oral or rectal, but I prefer.... Oh, sorry, different topic.

But with stove thermometers, Confucius says, "A man with one stove thermometer always knows the exact temperature, a man with two stove thermometers never knows what the temperature is."

Definitely seems strange that the sides are hotter than the top, but a lot can go into that. Is the top on a 'second shell' or some sort of air gap and the sides are directly on the firebox? Different types/style of thermometer? Could just be that they are that far off. These old spring dial thermometers aren't precision measuring instruments by any means. Pics would help a lot.

 

[bholler]

Best place to take temperature... well, I think the standards are oral or rectal, but I prefer.... Oh, sorry, different topic.

But with stove thermometers, Confucius says, "A man with one stove thermometer always knows the exact temperature, a man with two stove thermometers never knows what the temperature is."

Definitely seems strange that the sides are hotter than the top, but a lot can go into that. Is the top on a 'second shell' or some sort of air gap and the sides are directly on the firebox? Different types/style of thermometer? Could just be that they are that far off. These old spring dial thermometers aren't precision measuring instruments by any means. Pics would help a lot.

It's definitely possible it's a convective top. Also just that the fan is cooling it. Because the top should typically be the hottest spot.

 

[Highbeam]

I can literally blow on my magnetic surface thermometers and the dial moves to indicate colder. The insert's blower fan does the same thing by blowing air over the upper thermometer's bimetallic coil and giving a false low reading. It's not that the actual surface temperature is changed much by the blower but that the instrumentation has this weakness. All temperature readings with coil thermometers in areas of forced air movement should be taken minutes after shutting off the blowers.

And 800 anywhere on the stove is about what I would call abuse.

 

[Theonion]

So follow up. I have a gun type thermometer and with just 4 pieces of wood the sides are getting to about 750, sometimes it just reads "hot" for over 800 degrees. Meanwhile the top is about 500. And yea it's a buck 74 so there is a blower cooling the top.

I really Don't feel like 4 pieces of wood should be causing an overtired situation, I've run this stove for 10 years like this but just recently started checking the temps. Now from what I've read 700 is pushing it so I've been loading less wood in it to keep the temps down and my house is not as warm as I would like. Might be time to upgrade to a bigger unit.

 

[Corey]

If the metal has direct exposure to the fire on the inside and you're measuring the direct outside surface, then I could see it hitting 750/800 pretty easily. Here is a video I made years ago. Time lapse of the nightly burn condensed into one minute. The peak temp on the top of the stove is 880°F (green display in the lower right corner) at 0:23 time. This is the top/center of the stove with the blower on full.

To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.

Accept third party cookies

I''ve seen similar quotes of 700° being an 'overfire' = but I'm not really sure where that comes from or why it would apply as a blanket number to all stoves. I've had this stove for 20 years and it was 'well used' when I got it. So far, I don't see any indication that a nice 'warm' stove or 'hot' secondary tubes are causing any deterioration.

Burnin' Orange Tonight!

Maybe this is why they call it 'Osage Orange' aka 'Hedge'? Just settling down into a nice 700ºF cruise to warm the house up for the evening. Thought the burn tubes looked nice and pretty orange, so I snapped a photo. The pic really doesn't do justice to actually being here and feeling the...

www.hearth.com

I guess there are a few things to consider in keeping the stove under control:

- Are all gaskets and other air controls on the stove in good working order? If you have leaky gaskets or misadjusted air controls that can cause the fire to burn hotter than intended
- Do you have an extremely tall / well insulated chimney? Seems like when people start getting into 25-30ft of flue pipe, then start mentioning 'overdraft' situations where the stove burns hotter than desired. Sometimes installing a damper is needed.
- Is the blower running at full speed and with good air flow? Sometimes dirt/dust on fan blades or intake can restrict airflow, and low voltage or worn bearings can reduce fan speed. Any of these can mean less airflow and a hotter stove with less heat into the room.

 

[begreen]

So follow up. I have a gun type thermometer and with just 4 pieces of wood the sides are getting to about 750, sometimes it just reads "hot" for over 800 degrees. Meanwhile the top is about 500. And yea it's a buck 74 so there is a blower cooling the top.

I really Don't feel like 4 pieces of wood should be causing an overtired situation, I've run this stove for 10 years like this but just recently started checking the temps. Now from what I've read 700 is pushing it so I've been loading less wood in it to keep the temps down and my house is not as warm as I would like. Might be time to upgrade to a bigger unit.

Are the interior firebricks all in good condition? Also, check the secondary manifold feeding the secondary tube for leakage on the sides. This may show up as unusually strong flames right above the side firebricks. How does the paint look on the sides? Is it greyish or white?

The blower will cool down the top by 100-150º. So maybe it is actually at 650º without the blower running. If so, that's a normal operating temperature. If so I would keep running it the same as you have been. For now, you need heat. Just don't get it so hot that the stove starts glowing on the sides.

 

[Theonion]

I hear what your saying. This is an insert with on a 2 story house so I'm guessing the chimney is about 25 feet tall, since it's an insert it's impossible to put a flu dampener on.

Here is a pic, this is with the air control fully closed, this is the first fire of the day so the stove was cold, with 4 pieces of wood. Side temps are 600 top is about 450. That's fine but when I go to reload it the temps shoot up to 7-800 on the sides.

The firebrick was all replaced this past summer. I don't see any discoloration on the paint anywhere, it's still more or less black

 

[begreen]

I hear what your saying. This is an insert with on a 2 story house so I'm guessing the chimney is about 25 feet tall, since it's an insert it's impossible to put a flu dampener on.

Here is a pic, this is with the air control fully closed, this is the first fire of the day so the stove was cold, with 4 pieces of wood. Side temps are 600 top is about 450. That's fine but when I go to reload it the temps shoot up to 7-800 on the sides.

The firebrick was all replaced this past summer. I don't see any discoloration on the paint anywhere, it's still more or less black

View attachment 306234

That looks normal, but maybe 2-3 hrs away from a reload.

 

[Theonion]

That looks normal, but maybe 2-3 hrs away from a reload.

I think I need a bigger stove because to keep the house warm I'm needing to either add a log an hour or full reload every 3. I'm thinking of the buck 91

 

[Flame Monger]

To the picture posted December 26 2022. Brother I have a buck 74 professionally installed in 2020 as a stove insert. I burn like that and with even more wood hotter than that all the time. I still got black paint on this thing. The seals look brand new. The gasket on the door looks brand new and I love it. I have a single story ranch home just over 2,000 square feet roughly and this thing does pretty well. Problem is some of the rooms are harder to get the heat to and they are a bit colder at night so we use space heaters. I'm not sure if I'm abusing it or not, but it seems to take whatever this style of use is just fine. As a side note for mine, I work in a thermal industrial environment where I can get material to rebuild this for probably just over cost. This stuff is for a high temperature furnaces that get over 2000 c and even hotter. I wonder what that carbon type insulation would do to the buck. 74. No need to rebuild anything. It all still looks pretty good aside from a busted insulated board that my kid knocked a chunk out of a couple years ago. Also, I run this and the baffles sometimes start glowing but it doesn't appear to do any damage.

 

[Flame Monger]

Drop me a line if you want, or have any questions. This stove is very easy to operate once I began to understand the basics.