New Installation Temp and Pressure Gauge Location Questions

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begreen

Mooderator
Staff member
Nov 18, 2005
96,492
South Puget Sound, WA
Begreen, there is much written about flue gas temps, but I'm wondering if you could offer a guess a range you would want to see my install at. I will be approximately 8 inches above the unit. Best I can do with an insert. I understand best is 18 inches above.
Take a look at my postings in the starting a fire thread. They include the operational flue temps via a probe thermometer for our stove which has a similar firebox to your Summit, though our stove is older and does not have the EBT2 regulated secondary air.

Note that the flue temps in that thread are taken about 21" above the stove. You will likely see higher temps due to the lower probe, but the thread will at least provide some relative temps to start with.

 
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davidmsem

Minister of Fire
Oct 30, 2014
628
New haven, Connecticut
Take a look at my postings in the starting a fire thread. They include the operational flue temps via a probe thermometer for our stove which has a similar firebox to your Summit, though our stove is older and does not have the EBT2 regulated secondary air.

Note that the flue temps in that thread are taken about 21" above the stove. You will likely see higher temps due to the lower probe, but the thread will at least provide some relative temps to start with.

Thank you!!
 

davidmsem

Minister of Fire
Oct 30, 2014
628
New haven, Connecticut
So I am still searching for a place to put my Dwyer magnahelic probe with the limited space I have.

Bholler advised, "Above the damper won't tell you anything about what suction the stove is seeing. "

I am convincing myself this is 100% correct and have built a little rig downstairs of 6-in pipe with a damper in it. I have a fan providing vacuum simulating a hot flue. As the damper closes, the magnahelic measures higher water column above the damper than below the damper. As the damper closes, above the damper experiences higher suction, below the damper lower suction. The exact reason why you install a damper.

So with the limited space I'm conducting more experiments to see where would be the best place and I actually stumbled on a rather fascinating discovery. Absolutely blew me away and just excited enough to write here before I go off to bed. There is definitely a best place to locate this thing in the limited space that I have. I'll conduct more experiments and gather more data. I never want to install a stove because I over fired ever again.

I'm including a photo of The limited space I have for installing a magnahelic sensor.

Also some pictures of the rig in various configurations .

Also installed an Auber Instruments temp probe, thanks bholler again, so i can measure temp inside the flu. Have a remote unit in the bedroom. Plan is that bedroom unit can wake up Kim to load more wood when the fire drops in temp. Haven't told her yet.

More to come . . .

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begreen

Mooderator
Staff member
Nov 18, 2005
96,492
South Puget Sound, WA
Fantastic. Can't wait until you get the stove running this winter. This will be the best-instrumented insert on Hearth.com.
 
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stoveliker

Minister of Fire
Nov 17, 2019
6,340
Long Island NY
I'm thoroughly impressed. Are you trying to get a job at a stove mfg R&D dept?

You're doing awesome. Don't think about the history, keep thinking and learning about how the stove operates.

I'm eager to read about what you discovered.
 
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davidmsem

Minister of Fire
Oct 30, 2014
628
New haven, Connecticut
I think I have located the correct place and probe depth for a Magnehelic device for my specific installation.

I have just finished rolling up the data and summarizing.

I welcome a peer review to help steer me if there is something wrong in what I did.

Additionally, this may be helpful for anyone else in this position (typical of insert installation). Is so, then it was really worth the time.

Conclusions are from bench testing where I assumed the bench vacuum at 6" below the damper would approximate the conditions experienced by the firebox. All I tried to do was find the correct location for my magnehelic probe using that assumption.

IF real life proves out to be close to my bench, even with VERY LIMITED space, careful placement will result in accurate measurements, within 0.02 in-col of water.

Please review and let provide feedback. I've got months of time to re-run any experiments before DRILLING a hole.

I tried to make a concise summary, but then again, I've been close to this issue since February.

Interesting to note that "path of the damper" will play a key role for me as I try and control my new appliance. There will be a "correct path" and "incorrect path" to maximize measurement accuracy.

Thank you again.

David

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