Thermomater magnetic or ir
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I have a stove-pipe thermometer on my stove top. Doesn't read accurately, but it does read the same every time. Now that I know how the stove burns, I know (relatively) how hot it is by where the needle is.
I have a stove-pipe thermometer on my stove top. Doesn't read accurately, but it does read the same every time. Now that I know how the stove burns, I know (relatively) how hot it is by where the needle is.
Missouri Frontier
Feeling the Heat
Backwoods Savage
Minister of Fire
Most inserts are difficult to get a good reading on. If I had one I'd use an IR gun. We have a free standing stove and have 2 thermometers and an IR gun.
Studdlygoof
Member
Can someone explain the concept of knowing stove pipe temps? New to stoves and haven't heard of this one before?
xman23
Minister of Fire
I have 4 or 5 of the stove top magnetic for years. They all read about the same. I recall one of them got a very distorted bimetal, so it went in the garbage. I just go a IR, fun but not needed. It confirmed how close the magnetics are. Remember there are different temps at different places on the stove, but they will all be relative with each other. My single wall pipe out of the stove, at the base has the same outside temp as the stove top in the back corner. I have 8 ft of single wall. The outside at the top is 100 degrees F cooler than the base.
I'll give you the basics, some one can correct the numbers. You need to keep the temperature of the flue hot enough to prevent condensing of the flue gasses. Internally above 250. If you measure the outside of single wall, the inside is 150 above that.
Studdlygoof
Member
So the therm needs to read 100? I'm assuming the temp is regulated through the air controls too? Sorry if these are dumb questions but I'm really new at this. I'll definitely be paying attention to this thread.
I moved this over to the gear room, but depending on the direction, the hearth room could have worked too.
Regardless, an IR is great because it can be shot anywhere no the unit which works great to help get some initial data points for how hot things are where when X is going on inside the stove.
A magnetic is nice because it does the same thing, but yet doesn't need to be picked up and utilized,,,, it's always right there.
If going magnetic I'd suggest a condar unit over a rutland or similar found in many big box stores.
If going IR, I suggest one with a temp range up to at least 900 if not 1000 degrees, and use the ratings on a place like amazon to help with the purchase.
In all, I suggest both, but if the type of insert (this is good info to put in a signature) were mentioned others may be able to give more accurate suggestions as to the viability of a magnetic.
pen
Regardless, an IR is great because it can be shot anywhere no the unit which works great to help get some initial data points for how hot things are where when X is going on inside the stove.
A magnetic is nice because it does the same thing, but yet doesn't need to be picked up and utilized,,,, it's always right there.
If going magnetic I'd suggest a condar unit over a rutland or similar found in many big box stores.
If going IR, I suggest one with a temp range up to at least 900 if not 1000 degrees, and use the ratings on a place like amazon to help with the purchase.
In all, I suggest both, but if the type of insert (this is good info to put in a signature) were mentioned others may be able to give more accurate suggestions as to the viability of a magnetic.
pen
maple1
Minister of Fire
I have magnetic, and IR, and a probe type.
I would get all three. The probe gives a much better indication of internal pipe temps, and can be permanently mounted in the pipe. The magnetic could be moved around to various places on the stove top or front or wherever & left there as long as you need to leave it. The IR can be used in all kinds of places for all kinds of things - and is neat to play with.
I would get all three. The probe gives a much better indication of internal pipe temps, and can be permanently mounted in the pipe. The magnetic could be moved around to various places on the stove top or front or wherever & left there as long as you need to leave it. The IR can be used in all kinds of places for all kinds of things - and is neat to play with.
Yep, a probe is great for double wall pipe. I wouldn't recommend one for single wall pipe though (just not necessary and the warning zones will be in the wrong place due to increased radiant heat hitting the thermometer's coil)
pen
pen
maple1
Minister of Fire
My probe doesn't have warning zones - just temps. It's in a single wall pipe.
Not sure about the increased radiant heat thing? Surely that would not increase the temp display more than what the internal pipe temps are that it would be reading & displaying? Or is that what you mean? I have a magnetic right beside the probe on my single wall - the magnetic reads at least 100°c less than what the probe does (200-225c) at full burn. IMO magnetic guages can be quite misleading (although maybe some might be "calibrated" better than others), due in part to pipe surface temps being a lot cooler than what they are in the middle of the pipe, and partly due to the small airspace between the surface of the pipe and the coil.
Not sure about the increased radiant heat thing? Surely that would not increase the temp display more than what the internal pipe temps are that it would be reading & displaying? Or is that what you mean? I have a magnetic right beside the probe on my single wall - the magnetic reads at least 100°c less than what the probe does (200-225c) at full burn. IMO magnetic guages can be quite misleading (although maybe some might be "calibrated" better than others), due in part to pipe surface temps being a lot cooler than what they are in the middle of the pipe, and partly due to the small airspace between the surface of the pipe and the coil.
Depends on the probe's design, but if it is one that is meant for double wall pipe, then it won't read accurately on single wall pipe.
The problem with a good many of the probes is that the metal probe just conducts heat back to the coil that's behind the face of the thermometer. Since the surface temps of single wall are so much higher than the surface temps of double wall, it can make them read high and not be a true reading of internal temps.
In general, if there is a blank faced one like you have (and I do as well) then it can be used even if the temp it is displaying is inaccurate, so long as it reads consistently.
Don't mean to derail this thread, but this older discussion may be of interest to you @maple1 https://www.hearth.com/talk/threads/is-this-flue-temp-probe-full-of-it.46304/
The problem with a good many of the probes is that the metal probe just conducts heat back to the coil that's behind the face of the thermometer. Since the surface temps of single wall are so much higher than the surface temps of double wall, it can make them read high and not be a true reading of internal temps.
In general, if there is a blank faced one like you have (and I do as well) then it can be used even if the temp it is displaying is inaccurate, so long as it reads consistently.
Don't mean to derail this thread, but this older discussion may be of interest to you @maple1 https://www.hearth.com/talk/threads/is-this-flue-temp-probe-full-of-it.46304/
maple1
Minister of Fire
Hmm, that was an interesting read - all 10 pages & two threads of it.
My probe is different than discussed in those. I just took a couple quick pics:
Just lit a fire so temps just building - usually it's more like 200c on the probe & 100c on the magnetic. Those bimetal type probes talked about in the other thread sound like all kinds of trouble.
My probe is different than discussed in those. I just took a couple quick pics:
Just lit a fire so temps just building - usually it's more like 200c on the probe & 100c on the magnetic. Those bimetal type probes talked about in the other thread sound like all kinds of trouble.
maple1
Minister of Fire
Came with my boiler. Made in Sweden, I forget now the brand - I can check it again when I go back down there.
I suspect they can be purchased from my boiler vendor & site sponsor Smokeless Heat. I don't know how much they cost but would be curious about it.
I was kind of shaking my head at that other thread - I would expect a probe thermometer to read the temps where the probe is located, and that the temps where the guage head is at would have no bearing. Sounds like a very badly engineered product to me - and very misleading & potentially dangerous. I had no experience with them until I saw that thread - I guess I won't be so quick to simply recommend a probe thermometer anymore.
I suspect they can be purchased from my boiler vendor & site sponsor Smokeless Heat. I don't know how much they cost but would be curious about it.
I was kind of shaking my head at that other thread - I would expect a probe thermometer to read the temps where the probe is located, and that the temps where the guage head is at would have no bearing. Sounds like a very badly engineered product to me - and very misleading & potentially dangerous. I had no experience with them until I saw that thread - I guess I won't be so quick to simply recommend a probe thermometer anymore.
Pen - for clarification (and tired eyes from reading the other posts).
Assuming that all readings are accurate...
If a surface temp is at 400F - is the internal temp 800F or 600F?? (the old half of internal or 50% of external argument.)
Assuming that all readings are accurate...
If a surface temp is at 400F - is the internal temp 800F or 600F?? (the old half of internal or 50% of external argument.)
not even close!
But I have single wall pipe. The whole idea of me getting in touch with condar is that their packaging claimed the probe would work on single or double wall pipe. My concern was that if someone used it on single wall pipe, and they didn't know better (new burner) that they would run the stove WAY too cool since the probe reads WAY too high on single wall, and could increase their chances of a chimney fire from burning that cool.
They changed the packaging to state that it is for double wall use only. Their website too http://www.condar.com/probe_meters.html reflects in bold that the probe is meant for double wall pipe and that their is a no-drill magnetic for single wall.
I gave my one probe to a cousin with double wall chimney, and kept one that is just numbers (a new old stock condar unit) and no warning zones on the stove pipe way up at the 90 degree bend.
pen
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