Exiting air temp

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ltlhawk

Burning Hunk
Nov 24, 2012
111
Pelham, NH
Hello everyone,

I got my first pellet stove and so far I am loving it. I bought a GC60 and installed it yesterday. Took me a few to figure the control out and although the unit does heat the house I am a bit surprized at how low the temperature coming out of the stove is. I went to the place I bought the stove today and checked out some of there other stoves and I could not put my hand directly in front of the blower exit because it was way to hot. And that was with their stove set at 1/2 max. With my stove on full max I measure only 150 degrees F. I can eaqsily hold my hand directly in front of the exit air. The CG60 is rated at 55000 BTU and I cant believe that that is what is coming out. Does anyone have any suggestions?

Thanks
 
Room air temperature out of the stove is not a measure of heat being put into the room.

You need to account for the differences in the air flow volumes to determine what the heat output is. Also the 55,000BTU maybe the input rate and not the output rate. I don't know what figures were released for the GC60.

And with a pellet stove that is running on a fixed firing rate pellet choices can make a huge difference.
 
Smokey,

Thank you for responding ,as you can tell I am new to all of this. I was just comparing the air coming out of the units at the Stove store to the air coming out of my stove and there is a huge difference. The stove is rated to support 2200 square feet and I guess I was expecting more out of it then what I get now.. I will continue my research and learn more about pellet stoves in general. I have read a lot of posts here and it is a great place for information.. thank you
 
Do you have an OAK? If not, that could be part of the problem.
 
If you want some idea of pellet choice differences you should see the pellet reviews done by hearth.com member jtakeman, the ones on here are old now but the same thing is likely still the case.

https://www.hearth.com/talk/threads/2010-pellet-review-its-that-time-again.54880/

He describes how the tests are done and he doesn't play games, he uses this information to help him select what pellets to buy.
 
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good stuff.. I am not even sure what the pellets are as I bought my first two bags at the dealer just to get me started. I will have to check.. I think my next step is to read over that review you suggetsed Smokey and educate myself on pellet selection.. I did not realize that there is such a big difference in pellets. thanks guys
 
Smokey,

I just read some of your post on the pellet tests.. WOW.. it sounds like you were measuring your air temp similar to how I was measuring mine and my measurements are no where near what your average temp is. I cant get more than 150 degrees about 2 inches from convection output. I gotta keep reading.......
 
There is a lot more to look into. Not the least of which is what the other stoves you were comparing things to were in order to factor the air volume amounts into the consideration.

Apples to Oranges comparison isn't a good thing.

Also relying on a square footage figure which I'm certain has an asterisk by it is an ever loving joke.

Your house even if it is a 1000 square foot one and your neighbors house of exactly the same square footage may or may not be heatable by a particular stove rated to heat 2000 square feet. His might be and yours not or yours might be and his not.
 
Smokey,

I just read some of your post on the pellet tests.. WOW.. it sounds like you were measuring your air temp similar to how I was measuring mine and my measurements are no where near what your average temp is. I cant get more than 150 degrees about 2 inches from convection output. I gotta keep reading.......


They aren't my tests and that unit is not the same as yours. What those tests will tell you is that pellets are not all the same and do not produce the same results when burned in the same stove with the same settings.

Now Jay's stove was properly setup.
 
understood.. Thanks again for your advice. I will do some measurements and adjustments and see which settings make what changes..
 
When the stove was installed did they put a meter to it during the installation in order to correctly set the damper?
 
The higher the heat setting, the faster the convection blower spins.

The faster air results in lower output temps.

A lower setting (3 or 4) will produce a higher output temp normally. Because the air travels slower and has more "dwell" time to extract the heat.

I get higher temps on Low, than I do on Med on my Quad. Slower air = Hotter air. YMMV
 
At higher heat settings, as the fan runs faster and output temps may be lower, you're still getting more heat.

My stove doesn't work quite that way - higher heat settings increase both fan speeds, but the output temperature climbs about 50 degrees per step. At step 4 you can't stand within 5 feet of the front of the stove for long - it gets hot!
 
The result coming out those tubes depends on a lot of things a well designed and executed stove should have as much of its heat removed from the heat exchanger and sent into the room as possible.

A truly well designed unit can do this with no increase in the air temperature exiting the stove into the room.

These folks have mastered the removal of heat.

There is a formula that goes something like this the BTU entering the room via the convection system is equal to a constant times the difference in the temperature of the the output air and the input air times the blowers air volume at each setting.

BTUs = c X ::DTt X airflow c is different for each gas and there is a table available for each gas and for normal air.
 
The heat removal is also governed by how well the exchanger can transfer the heat on the combustion air side to the room air side.

This is also describable by an equation and this is where things can get complicated because of things like ash and dust which gradually reduce the effectiveness of the heat exchanger over time.
 
One thing to keep in mind is that all that cast iron does take a few hours to fully heat up. My M55 is topping out at about 245F on heat level 3, feed trim 2. That is measured at the 2nd from the left heat exchanger tube. With that info you should be able to make a pretty good comparison with your stove, since it's pretty much the same stove as my M55. The middle tubes air is much cooler. So you have to compare apples to apples. However, at full blast your stove should be so hot that you don't want to stand in front of it for long, and the flame should be very big and up into the heat exchanger tubes. You will need to be burning the same pellet as your dealer so it's a fair comparison with his stoves. Also, I think your real problem is that your stove may have come with an adjustable auger cover and it may be set too low which would restrict the amount of pellets that can feed. I would look there first, and adjust it wide open (all the way up) and see what you think. It is in the hopper and covers the auger. You should be able to loosen the screws and slide it up to expose the auger to the pellets better.
 
BTW ltlhawk, welcome to the forum.

By now you should have some idea of a few of the factors that affect what you are going to see for temperatures out of the tubes and that there are a bunch of folks on here that will help you sort things out.

The important thing is it all starts with the installation and setup of the stove.

How's the reading going?
 
UPDATE: The stove has been running now for a total of 4 days and I have been using the stove as is and it has been heating the house just fine, but it continues to bother me that I can not get a real strong hot air flow out of the stove. I decided to check the damper today and found that the screw that holds the slide in place was completely loose and the slide was all the way shut. I do not have the gauge needed to properly set up the WC so I used the procedure outlined in the sticky on the top of the forum page but I find that there is almost no change when I move the slide from one extreme to the other. The flame does go down a little bit when I move the damper from full close to full open, but not much change. I tried every position in between as well and there is not much change at all. This leads me to believe that I might have a draft problem, but I am not sure as I am but a noob. I accidentally touched the exhaust blower and nearly burnt my hand off, i think that this is normal, but do not know for sure. Tomorrow I think I will disconnect the pipe right at the Tee and make sure I have blower. Should be an easy test.
 
You have to do all adjustments in small increments with plenty of time between to really see the effects of the adjustment, doing it by eye is a skill not easily mastered by anyone who isn't patient.

Why don't you detail your vent system for us.
 
I can do that.. My stove is placed in front of my pre-existing gas fireplace. I removed all the gas stuff and placed the stove so the back section is just inside the fireplace. I have an appliance adapter connected to the stove and then to a 45. That is connected to the Tee. From there it is 13 feet straight up through the existing 8" fireplace exhaust. I terminated at the top with a simple rain cap. I made 2 plates to cover the difference between the 4" pipe and the 8" pipe so that there is no open space between them and caulked with high temp red cauking. This keeps the 4" pipe centered inside the 8" pipe.
 
yeah.. I think that is the best thing to do. I was pricing them out and saw it would cost about $65, so I will just go ahead and do it right. is there a place I can get one tomorrow, like a Home Depot or something.. I dont want to wait for shipping.
 
ah.. understood.. Sounds like a good project for the morning.. Thanks again Smokey for your advice.. I am lovin this forum. I do not post a lot but I have been reading every post and just sucking up the info (that didnt sound very good)...... I love learnin new stuff. I am the type that dives in head first and then thinks later if the water is deep enoguh.. haha. I have my lawn tractor transmission all disassembled in the basement and am working that project at the same time.. muhahahahahahaha. its a sickness, I know.
 
Ltlhawk, did you check the adjustable auger cover in the hopper? I set my damper by eye until I finally got a mag. All I did was confirm my eye was as good as the mag. Anyways, if it were me, I'd set the damper about 1/2 open, then check your adjustable auger cover. It may be all the way down which will severely limit the amount of heat the stove will put out by restricting the pellet feed rate.
 
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