For some background to understand why BeGreen sent his older condar probe from Washington State to Pennsylvania to test it compared to my new condar probe, you can read up here.
https://www.hearth.com/talk/threads/51149/
https://www.hearth.com/talk/threads/51880/
https://www.hearth.com/talk/threads/69677/
Brief Background.
About 1 year ago I purchased a Condar Probe meant for single or double wall pipe. When it arrived at my home it was damaged and they sent another. As I started using the probe I soon realized that when installed according to the instructions, this thing was showing my stove pipe temps to be maxed out with a stove top of only 500 degrees! After testing both probes I had against each other and finding them equal, I contacted Condar and a dialogue began. It was decided that I should send back my damaged unit to them to test in condar's test furnace to check it's accuracy. The results came back near perfect.
The problem
If this probe reads near perfect, then why it is showing temps in the unsafe zone when my pipe surface thermometers and IR thermometers are saying things are OK? Who do you believe?
Hypothesis:
My theory was that radiant heat which would be much greater on single wall pipe as compared to double wall was affecting this probe even though the packaging claimed it shouldn't. After a series of tests (which can be viewed in the top thread I linked to at the beginning) I found that radiant heat did in fact make it read warmer.
Further testing led me to make an insulator (check out the 3rd link above) to try and simulate double wall stove pipe temps for my probe. When doing this the readings dropped and seemed reasonable. What would have been a 1200 degree temp w/out the insulator was reading roughly 1000 with it.
At this point, I figured problem solved in that the company simply should not have claimed that the probe works well on single wall pipe because there is too much radiant heat there, but can be trusted on double wall because of the added insulation. So we began wondering, what about the old tried and true probes that also carried this claim which people have used for years and have provided readings that seem reasonable?
Well, to test just that BeGreen sent me his 20 year old probe and I tested them against each other. As it turns out, the old probe meets the packages claim that it will provide reasonable temp readings on single wall pipe. It ran almost consistently 200 degrees less than my probe thermometer at operating temps. With both probes at room temp, they would read identically.
The conclusion:
I like my probe thermometer, it reads consistently I just have to mentally adjust where the "redline" is from 900 to 1100 degrees for cruising since this new probe is reading higher than it should be about 200 degrees. On startup, I will occasionally take it to 1250.
On double wall pipe, I think the temps and scale should be fairly accurate and trustworthy. As such, cruising should be kept at about 900 and it shouldn't get much over 1000 on start up.
Further questions:
What the heck is different? Why does the old read reasonable and the new is high? Condar claims they are identical probes other than an updated face plate. A visual inspection also shows they look identical and the size of the scale on each is the same.
I think that condar was wise enough to make seperate flue and stove top surface thermometers with different scales on them to account for differences in operational temps there, why not do the same for the probe thermometers and make one faceplate for single wall pipe with an updated scale and keep the current one for double wall pipe?
Here's some pics to show you what I found.
Your comments are welcome as always.
Thanks BeGreen for making this possible.
pen
https://www.hearth.com/talk/threads/51149/
https://www.hearth.com/talk/threads/51880/
https://www.hearth.com/talk/threads/69677/
Brief Background.
About 1 year ago I purchased a Condar Probe meant for single or double wall pipe. When it arrived at my home it was damaged and they sent another. As I started using the probe I soon realized that when installed according to the instructions, this thing was showing my stove pipe temps to be maxed out with a stove top of only 500 degrees! After testing both probes I had against each other and finding them equal, I contacted Condar and a dialogue began. It was decided that I should send back my damaged unit to them to test in condar's test furnace to check it's accuracy. The results came back near perfect.
The problem
If this probe reads near perfect, then why it is showing temps in the unsafe zone when my pipe surface thermometers and IR thermometers are saying things are OK? Who do you believe?
Hypothesis:
My theory was that radiant heat which would be much greater on single wall pipe as compared to double wall was affecting this probe even though the packaging claimed it shouldn't. After a series of tests (which can be viewed in the top thread I linked to at the beginning) I found that radiant heat did in fact make it read warmer.
Further testing led me to make an insulator (check out the 3rd link above) to try and simulate double wall stove pipe temps for my probe. When doing this the readings dropped and seemed reasonable. What would have been a 1200 degree temp w/out the insulator was reading roughly 1000 with it.
At this point, I figured problem solved in that the company simply should not have claimed that the probe works well on single wall pipe because there is too much radiant heat there, but can be trusted on double wall because of the added insulation. So we began wondering, what about the old tried and true probes that also carried this claim which people have used for years and have provided readings that seem reasonable?
Well, to test just that BeGreen sent me his 20 year old probe and I tested them against each other. As it turns out, the old probe meets the packages claim that it will provide reasonable temp readings on single wall pipe. It ran almost consistently 200 degrees less than my probe thermometer at operating temps. With both probes at room temp, they would read identically.
The conclusion:
I like my probe thermometer, it reads consistently I just have to mentally adjust where the "redline" is from 900 to 1100 degrees for cruising since this new probe is reading higher than it should be about 200 degrees. On startup, I will occasionally take it to 1250.
On double wall pipe, I think the temps and scale should be fairly accurate and trustworthy. As such, cruising should be kept at about 900 and it shouldn't get much over 1000 on start up.
Further questions:
What the heck is different? Why does the old read reasonable and the new is high? Condar claims they are identical probes other than an updated face plate. A visual inspection also shows they look identical and the size of the scale on each is the same.
I think that condar was wise enough to make seperate flue and stove top surface thermometers with different scales on them to account for differences in operational temps there, why not do the same for the probe thermometers and make one faceplate for single wall pipe with an updated scale and keep the current one for double wall pipe?
Here's some pics to show you what I found.
Your comments are welcome as always.
Thanks BeGreen for making this possible.
pen