Flue temps

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Welderman85

Feeling the Heat
Nov 1, 2017
350
Chesaning MI
Hello all I installed this little avalon insert the tail end of last season and didn't get much burn time under my belt. I'm looking in to a remote read out but not sure how to attach it to my liner yet. I currently get my temps on a exposed part of my flex line just after the appliance connection probly 4-6 inches off the back of the insert. On the high and the low what should I be looking for temp wise. I usually keep it between 250 and 400 measured at this point with a ir temp gun.
 
That's probably about the maximum you want to see there.
 
It would depend on the stage of the burn. In the combustion (flame) stage over 250, but in the coaling stage if it is lower that would be ok. This is an estimate. What's more important is the internal flue gas temp. How much loss temp loss there is betwen the center of the flue and the surface of the appliance connector is a guess, especially that close to the flue collar.
 
How can I measure the internal temp. Its a 6" flex liner ? Also how bad is it to go to say 400 450. Thank you
 
If you follow the common belief that internal temperatures are double the skin temperature then 500 degrees on the surface is your redline. This corresponds to 1000 internal and is normally measured about 24” above the stove where it should have cooled in comparison to right at the appliance connection.

200-450 is the normal skin temperature range. Somewhere in the middle is safe and efficient.
 
If it's a heavy duty liner then it should be ok, but most are not heavy duty. a safer entry point for the probe would be the appliance adapter with a thinner liner. The temps will read higher.
 
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If it's a heavy duty liner then it should be ok, but most are not heavy duty. a safer entry point for the probe would be the appliance adapter with a thinner liner. The temps will read higher.
Actually the construction of the heavy liners would be hurt more by drilling a hole
 
Actually the construction of the heavy liners would be hurt more by drilling a hole

And since it is single wall construction wouldn't it be better to simply clamp on the washer type probe?
 
And since it is single wall construction wouldn't it be better to simply clamp on the washer type probe?
Absolutely. On heavy wall a properly placed screw or rivet would be fine as well. Those don't hold in light wall though
 
So if I was going to order a auber meter for my thin wall flex liner what one would I need ? So I could safely attach to the liner
 
So if I was going to order a auber meter for my thin wall flex liner what one would I need ? So I could safely attach to the liner
A band clamp to hold the sensor on
 
Big ass hose clamp and the “washer” probe option. You’ll be reading surface temperature.
 
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Absolutely. On heavy wall a properly placed screw or rivet would be fine as well. Those don't hold in light wall though
Surface readings are an approximation. What is the difference between a 1/8" hole for a screw and one for a probe in a heavy liner?
 
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Surface readings are an approximation. What is the difference between a 1/8" hole for a screw and one for a probe in a heavy liner?
The 1/4" hole for the probe would be more than half the width of a segment on heavy wall liner. Most manufacturers say no more than 1/8".

And surface readings are not an approximation. Just a different value than an internal measurement.
 
The auber directions say to drill a 1/8” hole for the probe.
 
The 1/4" hole for the probe would be more than half the width of a segment on heavy wall liner. Most manufacturers say no more than 1/8".
The probe sensor is 1/8".
And surface readings are not an approximation. Just a different value than an internal measurement.
How much different? If it's a guess, it's an approximation, especially if the surface probe does not react as quickly as the flue probe which is instant.
 
The probe sensor is 1/8".

How much different? If it's a guess, it's an approximation, especially if the surface probe does not react as quickly as the flue probe which is instant.
No probs I have installed only required a 1/8" hole.

Surface temps are perfectly acceptable yes it may lag by a few seconds behind a probe but that really won't make a bit of difference. I have run both with my auber. And both work just fine.
 
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For sure it is better than nothing, especially for an insert.
 
For sure it is better than nothing, especially for an insert.
The numbers will most likely be a bit off on an insert anyway because the sensor will probably not be 18" up from the stove. But any info will help once you figure out what works for your setup