Measuring Stop Top Temps

[kmachn]

This is probably a newbie question, but I want to make sure I'm doing things right to optimize the efficiency and secondary burns on my new Quadra-Fire.

When I'm measuring the stove top temperature of my Cumberland Gap, should I be measuring the "actual stove top"? I know, sounds stupid. But the reason I ask is because the top can be removed and there is about a 1"-1 1/2" gap between the steel firebox and the cast iron top. This is where the blower would go, if I purchased one (or decide to purchase one in the future). At any rate, the temperature varies greatly and if I start turning down the input air when it reaches the 400-500 F range, then I'm thinking the difference between the steel fire box temp (which I can estimate using my IR thermometer) and the actual cast iron top is going to vary greatly. Especially when I fire it up from cold. Appreciate any input, thanks a lot.

 

[soupy1957]

Having covered this ground in my own life, allow me to put in my two cents.........

I tried a variety of locations on MY stove, and still have a thermometer on the front flange face (if you look at an Avalon Rainier 90 online, you'll know what I mean about the front flange), but you wanna know how many times I actually look at it? Only accidentally, frankly.

Because of the fine leadership of many more knowledgeable folks in here, I installed a flue pipe thermometer, and gauge my burns from THAT thermometer only. The Stove thermometer simply tells me what the fire is: Hot. (and I knew that already).

That's not to say that over-heating the wood stove isn't an issue............but it IS to say that, HEY, the wood stove folks who designed the stove, knew it would get HOT in there, and built it rugged, and able to take it. Is over-heating a reality? Sure! Should I watch it.......sure. But I haven't OVER-heated my stove YET, and I've filled that bugger up pretty dang full, and got it pretty dang HOT, and I've not popped a weld YET.

The temps of the smoke going out the flue are (imho, and the opinion of others in here) MORE important, because your stove piping is (although also built to take it) more vulnerable to the heat; and the creosote that can build up in there, is like the crap that can build up in your arteries........and you know what'll happen if you don't monitor THAT, and keep THEM clear!

For "me" .........I watch the flue pipe temps exclusively..........(I've entered the "dark zone" as someone in here once told me).

Someone in here will fill in the gaps I've neglected, and will probably expand on what I've already said, but that's fine. They can explain it much better than me, THAT'S for sure!!


-Soupy1957

P.S.: One more thing.........I hope you have a wood stove that has a nice "viewing door" on it! The FIRST thing I look at (honestly) is the fire itself. How it's burning; what ITS doing. The flue "thermometer" is the SECOND thing I look at.

 

[Backwoods Savage]

Welcome to the forum kmachn.

Contrary to Soupy, we go by both stove top and flue temperatures and it works well. For your stove, there could be a difference in the heat if placed in the center but I doubt that would be more than 50 degrees. But it might take some experimenting to find out exactly what, if any difference there is.

One interesting thing I've noticed on our soapstone stove is that the temperature difference between stove top vs. placing more soapstone on top of that and measuring the difference is usually around 50 degrees but early on, from a cold start, that can be as much as 100 degrees difference.

 

[kmachn]

Sounds like I may need to think about putting in the flue thermometer, but being new to this I'm a little hesitant at this point to drill a hole (even a minor one) for a probe thermometer in my flue. I have DW stove pipe, so I'm guessing I need to go with the probe style, correct?

Glad to hear that you're getting differences of about 50-100 degrees. When the stove cold, the 100 degrees on my stove top is pretty much the difference that I've been getting also. I'm still learning what I can expect (as far as stove temps, optimizing secondary burns and burn times) and I absolutely do not want to overfire it. I have three small children and a VERY understanding wife, so there's too much for me to not use a measurement of some type. The stove top seems the least invasive at this point, but if I'm measuring the wrong spot and waiting for the wrong temperatures, I may be doing more harm than good.

We do have glass doors, and I absolutely watch the fire. But it seems like (and please correct me if I'm wrong on this) the fire can really get going and the fire gets hot enough to start getting secondary burns but not hot enough to maintain them when I start turning the primary air down. And I'm definitely a "quantify everything" kind of guy, so I like having the temperatures (even if they're not 100% accurate) as a ballpark to make sure it's not just my eyes deceiving me.

 

[soupy1957]

When "I" ordered my Flue Thermometer from Condar, (DW Flue pipe style) I was a bit nervous at first about compromising my "new" installation.

In the case of the Condar, it was easy. You drill a 1/4" hole first, thru both the inner and outer layers (18" up from the top of the stove), then you go back in with a 3/8" drill bit, JUST FOR THE OUTER LAYER (which means you have push gingerly). I did it, ........first try..........no issues.

When you install the thermometer, it'll go in and stay there. Reads well.

-Soupy1957

 

[Leaky Waders]

I actually have a similar problem as a noob woodburner. My fire looks good, feels pretty good (my blower, hooked to an automatic thermostat, comes on when the stove warms up) but once I start to throttle down the damper, its not long before I get a smoldering fire that dirties my door glass. My wood isn't perfectly seasoned, but with an insert, I can't measure flue temps, so a stove top thermometer is going to have to suffice. Any pointers on ensuring my stove is warm enough, please advise!

 

[CountryBoy19]

One interesting thing I've noticed on our soapstone stove is that the temperature difference between stove top vs. placing more soapstone on top of that and measuring the difference is usually around 50 degrees but early on, from a cold start, that can be as much as 100 degrees difference.

The temp difference between placing a solid object directly on another is going to be much lower than the OPs situation, which has the stove top separate from the firebox with an air-gap. The air gap will provide much more insulation value, and the top will be much lower than the box.

I have virtually the same problem. I have a zero-clearance fireplace which doesn't give me anywhere good to measure temp. The best I can do is a 3/4" wide strip of cast iron on the center of the door frame. It's a PITA to measure it there and I'm not entirely sure it's all that accurate either.

 

[Backwoods Savage]

I actually have a similar problem as a noob woodburner. My fire looks good, feels pretty good (my blower, hooked to an automatic thermostat, comes on when the stove warms up) but once I start to throttle down the damper, its not long before I get a smoldering fire that dirties my door glass. My wood isn't perfectly seasoned, but with an insert, I can't measure flue temps, so a stove top thermometer is going to have to suffice. Any pointers on ensuring my stove is warm enough, please advise!

To ensure the stove is warm enough watch the glass. If the glass starts to get dirty, give it more air. For sure what you describe says the wood could be drier. Hopefully you have next year's wood already split and stacked and if so, you will notice a huge difference in burning. You will be able to turn the draft down further and you will get more heat from the wood. Good luck.

 

[kmachn]

It sounds like what I am doing is working OK for now, and the differences between the steel firebox and the cast iron top I need to take with a grain of salt. I'm hoping to get a stove top thermometer soon and compare/contrast that with my IR thermometer, and likely a flue thermometer down the road. I guess the more of "toys" I have, the more likely I am to get to what I'm getting at...or something like that.

Soupy, thanks for the reassurance about installing the Condar probe thermometer in my flue pipe. That definitely sounds like something I can handle, with a little TLC.