How to measure heat output of Harman Accentra Insert?

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fullfatboy

Member
Sep 20, 2011
41
Washington Crossing, PA
Good Morning - I think I may be becoming a little over zealous with my new purchase. I keep thinking of new things to ask the forum.
However, I wanted to try different pellets to see which one's burn hotter. I also wanted to see how the settings on my stove affect the heat output. In order to do this I wanted to buy a Stove Top Thermometer. Do you have any recommendation on which brand to buy and more importantly, where it is placed on my stove? Do you place it where the heat is blowing out or somewhere else?
Thanks!
 
I have a simple food thermometer that is about 12 inches long and has an analog dial. I place it through the warm air exhaust grating and allow the tip to hang in air as oppose to touching metal. This is important you want to measure air temp.

It is great because being a meat thermometer it is graduated in 5 degree incriments and allows me to estimate between those incriments.

I do not necessarily care if the temp im getting out is 165 or 150 or 140. What I look for is the difference from pellet to pellet when running at steady state. That is the room temp is holding steady, the ouside air temp is reasonably steady (not comparing 45 degree and sunny to -10 and windy) and no-one is playing with the stove setpoints and fan speed is NOT fluctuating. All things being equal, I know what each pellet outputs in temp to the room.

I see some pellets that output 138 degrees and some pellets that output 165 drgrees, Note: cleanliness of the stove matters and will change that number by about 15 degrees. In other words after a cleaning on Sat AM when I start back up pellet A might run 170 but by Friday night before the cleaning that same pellet giving 155.
 
Your use of a meat thermometer certainly seems rational to me. When you clean your stove is this just scraping the pot and cleaning out the ash tray? What is involved? Sounds like it makes a big difference! THANKS!
 
I use a cooking thermometer also. But I use a digital electronic one. That gives an accurate readout. Also, make sure its not touching the steel. That way it only reads the air temp.
 
Food Professor said:
Your use of a meat thermometer certainly seems rational to me. When you clean your stove is this just scraping the pot and cleaning out the ash tray? What is involved? Sounds like it makes a big difference! THANKS!

My cleaning process is as follows.

1 Shut down stove and allow stove to go out and begin to cool down (usually 30 minutes for fire to drop and steel to cool down enough to handle)
2 Make sure the combustion fan is still running if not turn on stove and open door (set to manual start). The system will not feed pellets but the combustion fan will keep any smoldering or loose ash from falling in out of the fire box.
3 remove the logset and logset holder(wife likes it)
4 Using an old 3" paint brush I wipe down the inside of the firebox to lossen any fly ash into the ash pan.
5 scrape the burn pot out and remove all carbon. I use a 12 inch flat head screw driver to get between the carbon and steel.
6 remove the cover under the burn pot and suck with vaccum allow any ash to drop out. tap a couple times.
7 remove ash pan and dump in the garden (do not dump anywhere you do not want HOT ash and possibly glowing embers
8 vaccum the entire burn chamber out. I use a little shop vac with a special hepa filter. Do not use the standard filter (or you will be dusting everything) and DO not use a bag vaccum if you have warm ash or you will have a fire.
9 once the chamber is clean I remove the back cast iron panels one at a time and use the brush to brush off the fly ash off both the heat exchange and the cast iron panels.
10 every other week I run the cleaning tool up the exhaust vents
11 every 4th week I let the unit go really cold and pull the unit out and clean the combustion fan and the sensor there.
12 reassemble
13 clean glass with damp paper towel or magic eraser if really dirty
14 every 1 ton I do the leaf blower trick after everything is reassembled.

Total cleaning time is usally 15 minutes
1 hour total when pulling the unit away to clean the combustion fan
1 hour 15 minutes total time to do the leaf blower

Total down time from shut off to new fire is never more than 2 hours and usally less than 1.
 
Cleaning makes a huge difference on that Sat and sunday after the cleaning. but over time the fly ash builds up and there is a the law of diminishing returns. After two weeks I think I loose another 5 to 10 degrees but that loss of efficiency is slower. I'm of the opinion why not have the more efficient stove so I clean every week when I have to empty the ash pan. I figure it takes a few more minutes.

My brother has a XXV and he cleans once a month but he doesn't burn full time and he has a huge ash pan.
 
I find it difficult to measure the output air temp. It fluctuates up/down since the stove doesn't feed the exact amount of pellets each time. So, for me it ends up being more of an average temp from pellet to pellet. I tried this last year and if I remember right, the fluctuations were 50F or so.
Flynfrfun
 
I'm liking this thread! My Harman Accentra insert gets installed this weekend. I had 3 tons of Greene Team deliverd today and 1 of Great American from dealer. And yes.. I also bought a pallet jack. I think I need help.
 
JBWheel said:
I'm liking this thread! My Harman Accentra insert gets installed this weekend. I had 3 tons of Greene Team deliverd today and 1 of Great American from dealer. And yes.. I also bought a pallet jack. I think I need help.

Welcome aboard! Good luck with the insert. I have not purchased my pellets yet. I need to borrow a buddies truck.
 
Food Professor said:
What is the leaf blower trick?
Thanks! Great advice. MUCH APPRECIATED!

Do a search on here for Leaf Blower and you will see what it is. But the short story is it is a method to hook up an electric leaf blower to your exhaust pipe and SUCK out the bits of fly ash in the exhaust system. Takes about 15 minutes if done right and really cleans everything out as I run a chimney sweep doen the exhaust first to keep anythign from sticking. Note: do not point the exit nozzle (Blow side) at anything you do not want black....

There are a couple of post with directions and I do not want to be responsible for missing anything inreposting it.
 
JBWheel said:
I'm liking this thread! My Harman Accentra insert gets installed this weekend. I had 3 tons of Greene Team deliverd today and 1 of Great American from dealer. And yes.. I also bought a pallet jack. I think I need help.


NICE Pellet stash! You're gonna like the Great Americans & the Greene Teams are no slouch either. Good Luck & welcome to the forum.
 
flynfrfun said:
I find it difficult to measure the output air temp. It fluctuates up/down since the stove doesn't feed the exact amount of pellets each time. So, for me it ends up being more of an average temp from pellet to pellet. I tried this last year and if I remember right, the fluctuations were 50F or so.
Flynfrfun

I find the opposite. My flame hieght may vary a little (peelets dropping/burning/not burning/not dropping) but with my digital thermometer, I get very consistent temps. If I am burning on low (temp depends on pellet brand) my convection air temp is normally about 230* with X brand of pellets and the air temp never varies more than 3-4 degrees.

I have fojnd that this $19 thermometer that I got from target is the best tool in telling me the true heat output. Its a simple cooking meat thrrmometer thats clipped to my far right heat exchange tube and the digital readout moniter has a magnet on the back. So everytime I walk by the stove, I can see at a glance what the temp is. Looks like it came on the stove.

Its also a good indicator as to when you should clean your stove. After a week, the convection temp may drop 20* with the same pellet..

I have seen as high as 255* on Low with Somersets and a blistering 175* with Natures "Junk" . Thats a huge difference. But it let me know, to never buy those again. Also very ashy.
 
DexterDay said:
flynfrfun said:
I find it difficult to measure the output air temp. It fluctuates up/down since the stove doesn't feed the exact amount of pellets each time. So, for me it ends up being more of an average temp from pellet to pellet. I tried this last year and if I remember right, the fluctuations were 50F or so.
Flynfrfun

I find the opposite. My flame hieght may vary a little (peelets dropping/burning/not burning/not dropping) but with my digital thermometer, I get very consistent temps. If I am burning on low (temp depends on pellet brand) my convection air temp is normally about 230* with X brand of pellets and the air temp never varies more than 3-4 degrees.

I have fojnd that this $19 thermometer that I got from target is the best tool in telling me the true heat output. Its a simple cooking meat thrrmometer thats clipped to my far right heat exchange tube and the digital readout moniter has a magnet on the back. So everytime I walk by the stove, I can see at a glance what the temp is. Looks like it came on the stove.

Its also a good indicator as to when you should clean your stove. After a week, the convection temp may drop 20* with the same pellet..

I have seen as high as 255* on Low with Somersets and a blistering 175* with Natures "Junk" . Thats a huge difference. But it let me know, to never buy those again. Also very ashy.

When you say you saw 255' on Low, am I correct in assuming that the heat that is expelled from the unit is much hotter when the fan is not blowing hard. less air going through the system equals hotter air?
 
I think it is all about how the stove is set up and how it is running. If you have almost no airflow at the lowest distribution fan setting the thermometer reads very high if however you are pumping out the air with the distribution fan on high you will get a much cooler temp. It is for this reason I mentioned you need to be in steady state. The air can't be fluctuation and you can't be just turning on and heating the room.

It takes some experimentation but when you get to the point where the stove is running steady and it is clean then you have the ability to use this tool to grade pellets and to tell when it is time to clean as D mentioned.

Just my opinion take it for what it is.
 
Food Professor said:
DexterDay said:
flynfrfun said:
I find it difficult to measure the output air temp. It fluctuates up/down since the stove doesn't feed the exact amount of pellets each time. So, for me it ends up being more of an average temp from pellet to pellet. I tried this last year and if I remember right, the fluctuations were 50F or so.
Flynfrfun

I find the opposite. My flame hieght may vary a little (peelets dropping/burning/not burning/not dropping) but with my digital thermometer, I get very consistent temps. If I am burning on low (temp depends on pellet brand) my convection air temp is normally about 230* with X brand of pellets and the air temp never varies more than 3-4 degrees.

I have fojnd that this $19 thermometer that I got from target is the best tool in telling me the true heat output. Its a simple cooking meat thrrmometer thats clipped to my far right heat exchange tube and the digital readout moniter has a magnet on the back. So everytime I walk by the stove, I can see at a glance what the temp is. Looks like it came on the stove.

Its also a good indicator as to when you should clean your stove. After a week, the convection temp may drop 20* with the same pellet..

I have seen as high as 255* on Low with Somersets and a blistering 175* with Natures "Junk" . Thats a huge difference. But it let me know, to never buy those again. Also very ashy.

When you say you saw 255' on Low, am I correct in assuming that the heat that is expelled from the unit is much hotter when the fan is not blowing hard. less air going through the system equals hotter air?
Yes. You are correct. A higher fan rate equals cooler temps. Low fan rate means that the air has longer time in the exchange tubes. This is how I can heat my home to 76 with only using Low heat setting (until outside temps hit 0* or lower) I have a well insulated (2,180 sq ft) Ranch (w/ 2,180 sq ft basement) with newer windows and 1" of drywall (1/2" over existing 1/2") Stove in centrally located and we run a ceiling fan in the pellet stove room (dining room), one in the kitchen (far west side of house) and use corner doorway fans and ceiling fans in the bedrooms. House is 70 ft long and the temp in any room is no greater than 2 degrees different than the stove room. Large open lay-out and keeping the air moving, along with insulation helps tremendously.

And trickyrick. Yes. You are correct also. It takes some time. As there is a learning curve with anything. But this single tool, is a good one. Along with the leaf blower. Love these 2 things the most.
 
DexterDay said:
Food Professor said:
DexterDay said:
flynfrfun said:
I find it difficult to measure the output air temp. It fluctuates up/down since the stove doesn't feed the exact amount of pellets each time. So, for me it ends up being more of an average temp from pellet to pellet. I tried this last year and if I remember right, the fluctuations were 50F or so.
Flynfrfun

I find the opposite. My flame hieght may vary a little (peelets dropping/burning/not burning/not dropping) but with my digital thermometer, I get very consistent temps. If I am burning on low (temp depends on pellet brand) my convection air temp is normally about 230* with X brand of pellets and the air temp never varies more than 3-4 degrees.

I have fojnd that this $19 thermometer that I got from target is the best tool in telling me the true heat output. Its a simple cooking meat thrrmometer thats clipped to my far right heat exchange tube and the digital readout moniter has a magnet on the back. So everytime I walk by the stove, I can see at a glance what the temp is. Looks like it came on the stove.

Its also a good indicator as to when you should clean your stove. After a week, the convection temp may drop 20* with the same pellet..

I have seen as high as 255* on Low with Somersets and a blistering 175* with Natures "Junk" . Thats a huge difference. But it let me know, to never buy those again. Also very ashy.

When you say you saw 255' on Low, am I correct in assuming that the heat that is expelled from the unit is much hotter when the fan is not blowing hard. less air going through the system equals hotter air?
Yes. You are correct. A higher fan rate equals cooler temps. Low fan rate means that the air has longer time in the exchange tubes. This is how I can heat my home to 76 with only using Low heat setting (until outside temps hit 0* or lower) I have a well insulated (2,180 sq ft) Ranch (w/ 2,180 sq ft basement) with newer windows and 1" of drywall (1/2" over existing 1/2") Stove in centrally located and we run a ceiling fan in the pellet stove room (dining room), one in the kitchen (far west side of house) and use corner doorway fans and ceiling fans in the bedrooms. House is 70 ft long and the temp in any room is no greater than 2 degrees different than the stove room. Large open lay-out and keeping the air moving, along with insulation helps tremendously.

And trickyrick. Yes. You are correct also. It takes some time. As there is a learning curve with anything. But this single tool, is a good one. Along with the leaf blower. Love these 2 things the most.

Well I'm certainly looking forward to figuring this all out. At the moment I am waiting for a few parts to arrive, the temperature to drop, I have to buy pellets and I have no idea where and of course I will need some wine to enjoy once I get this baby up and running. Thanks for all the good tips and keep em coming!
 
Dexterday do you have a picture of the $19 thermometer you use I would like to try that this winter.
Thanks
 
AZ Pellet Guy said:
Dexterday do you have a picture of the $19 thermometer you use I would like to try that this winter.
Thanks

Yes. I can post a pic later. Out of the house now, gotta go to my Sons Boy Scout meeting tonight. Wont be home till after 8.

I used a wireless one ($35) but it broke after a couple days. I have a wired model now. Will post pics tonight.
 
Well... It took me awhile to get home.. One pic is it burning last season. The other is from today and I let the temp sensor (thermocouple) hang out..... I have a little steel clip that holds the Rod (thermocouple) in the middle of the tube. Cant see it, but you get the picture.

I take it out during the summer mon ths and put the log kit in..

Hope this helps... I hide the wire behind the right door. Like I said before, it looks like it came with it..
 

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Hello

If you want to measure the wood pellet stove heat output accurately and on it’s highest setting, The ONLY one I can recommend is the $25.00 digital Cole-Palmer and also purchase the high temperature heat probe. Most thermometers do not measure up to 1500 degrees like this one! My Avalon Astoria on low is 250 and high is over 600 degrees F !! see pics below:

See my post below
https://www.hearth.com/econtent/index.php/forums/viewthread/52626/

See cole-palmer web site
http://www.coleparmer.com/catalog/product_view.asp?sku=8646003

Large pic
http://www.coleparmer.com/catalog/large_image.asp?sku=8646003&img=86460_03 _05.jpg

This meter has a 4-ft. ribbon micro-cable that allows you to place the probe within an area and close the door without affecting the probe or the door seal. Accurately monitor temperature within freezers, water baths, heating blocks, incubators, refrigerators, and other areas. The meter includes a fast-response type-K probe that can be used for general purpose applications. Users can also choose from a wide verity of probe sold separately for surface, liquid, air or semi-solid materials.
What�s Included:
one beaded-wire type K probe, NIST-traceable certificate, leatherette case, and one 9 V battery
Specifications
Temp range -58 to 1382�F
Resolution 1�F
Accuracy �2�F .75% between 32 to 932�F and �2�F 1% between 933 to 1382�F. Below 32 accuracies are: -4 � 8�F, -40�F � 8�F, and -58�F � 10�F
Probe Thermocouple
Display 4-digit LCD, 0.7� high
Probe type Type-K
Probe(s) included Yes
Dimensions 2 3/4� W x 4 1/4�H x 3/4� (76 x 114 x 18mm).
Power 9-Volt Alkaline battery (included)

Good Luck
Don
 

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Don2222 said:
Hello

If you want to measure the wood pellet stove heat output accurately and on it’s highest setting, The ONLY one I can recommend is the $25.00 digital Cole-Palmer and also purchase the high temperature heat probe. Most thermometers do not measure up to 1500 degrees like this one! My Avalon Astoria on low is 250 and high is over 600 degrees F !! see pics below:

See my post below
https://www.hearth.com/econtent/index.php/forums/viewthread/52626/

See cole-palmer web site
http://www.coleparmer.com/catalog/product_view.asp?sku=8646003

Large pic
http://www.coleparmer.com/catalog/large_image.asp?sku=8646003&img=86460_03 _05.jpg

This meter has a 4-ft. ribbon micro-cable that allows you to place the probe within an area and close the door without affecting the probe or the door seal. Accurately monitor temperature within freezers, water baths, heating blocks, incubators, refrigerators, and other areas. The meter includes a fast-response type-K probe that can be used for general purpose applications. Users can also choose from a wide verity of probe sold separately for surface, liquid, air or semi-solid materials.
What�s Included:
one beaded-wire type K probe, NIST-traceable certificate, leatherette case, and one 9 V battery
Specifications
Temp range -58 to 1382�F
Resolution 1�F
Accuracy �2�F .75% between 32 to 932�F and �2�F 1% between 933 to 1382�F. Below 32 accuracies are: -4 � 8�F, -40�F � 8�F, and -58�F � 10�F
Probe Thermocouple
Display 4-digit LCD, 0.7� high
Probe type Type-K
Probe(s) included Yes
Dimensions 2 3/4� W x 4 1/4�H x 3/4� (76 x 114 x 18mm).
Power 9-Volt Alkaline battery (included)

Good Luck
Don

I never did any testing on High.. I heat mainly on Low. But 250 is a good average temp for our stoves. The Astoria and the CB 1200 are very similar.
 
Dexterday and Don 2222

Thanks for the Temp pictures and links
I will check out both this week
Eric
 
AZ Pellet Guy said:
Dexterday and Don 2222

Thanks for the Temp pictures and links
I will check out both this week
Eric

Yes Thank You! You guys have got me interested in checking my stove temperatures. I have a digital multimeter with a temperature probe, so I am going to dig that out and see what the specs are. Maybe in the future I will buy one of those stand alone units and dedicate it to monitoring the temp all of the time. I was wondering how people could tell the difference in temperature between pellet brands. I had a hard time feeling the difference between the brands I have used. Of course the pellets I had in the late winter and spring could have been similar enough that there was no difference to notice. I have the same two brands for this season. One thing I did notice of course is a difference in burn time and ash. Still so much to learn. Thanks again!
 
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