Super 27 running very hot

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Good point. I was assuming a new stove install. His manual quote seemed to be from the LE and so did the mention of the EBT. There's no harm in trying to close off that rear opening to see if it makes an improvement.

If this is a used stove, then I need to revisit other assumptions. There are other things that could be wrong like the secondary air feed linkage being uncoupled. It would help to know the year of the stove.

@alber197 what year is your Super?
 
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Good point. I was assuming a new stove install. His manual quote seemed to be from the LE and so did the mention of the EBT. There's no harm in trying to close off that rear opening to see if it makes an improvement.

If this is a used stove, then I need to revisit other assumptions. There are other things that could be wrong like the secondary air feed linkage being uncoupled. It would help to know the year of the stove.

@alber197 what year is your Super?
Sorry, I made a mistake in the title. I have a new super LE purchased this year. Is there a way for me to fix the title?

My manual states the same thing @begreen posted regarding the rear panel. It's a little confusing because it has a sticker on it that's says remove for room air but it's a little vague in the manual.
 
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I believe so. I have the Super Insert LE 2020 EPA model. I removed a metal piece from the front per the instruction manual for using room air. For the most part I find that the draft control has the dynamic range that I need to control the fire.

However I too have had the fire kind of "run away" on me, but only under certain conditions. It was a hot reload before bed time and there were still quite a bit of hot coals. I don't remember if I raked them forward. The STT was maybe 250-300F at time of load, hotter than usual. I packed it pretty good, 7-8 very dry hardwood splits. I opened the draft control all the way to get things started, then ratcheted it down over 30 min or so. Around then it was really cooking. STT close to 800F, draft all the way down, blowers on max, the flames still cruising, secondaries going strong. So I got onto this forum and read as much as I could for about 2 hours. By then it was slowing down and the temp started dropping. In the end I determined:
  • 800F is pretty hot, but probably ok and not quite an overfire. (usually the stove runs 600-700F max STT)
  • I turned the draft down too slowly for the conditions.
  • The wood was very dry.
  • I loaded too many splits on coals that were too hot and possibly didn't rake them forward.
  • I was going to be very tired in the morning.
My takeaway: Operating a wood stove is as much an art as it is a science. It can be a challenge, each fire is different, and that's what makes it fun.

In your case it does seem like maybe there's too much air getting in. Is it possible for you to turn the draft control down too early and get the wood to smolder, or will you always get flame? If you can get things cruising with the draft nearly all the way down that might indicate an air leak. On mine it's imperative to have the draft almost full open to get things going. For reference, it's got 25' of 6in liner in a masonry/terra cotta lined chimney.

Sometimes I can get things going with the intake closed down all the way or close to it. I think that is because coals are too hot and wood is very dry when I reload.

But if I mix the wood up and turn down quicker, it will eventually get to the same point, it will just take longer. If that makes any sense. It seems regardless of what I try or what wood I load, the secondaries will start roaring at some point with the intake turned all the way down.

And maybe there's nothing that I can do but it would be nice to have a little more control.

Flue probe is going to be installed this weekend and I will try a magnet over the boost hole.

Thanks everybody.
 
Thanks for the update. I will change the title for you.
There will always be a secondary bloom when the wood is at its prime outgassing stage but you should have a bit more control. Some metal duct tape can be put over the boost air hole if you can't find a magnet.
 
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A hot enough fire will melt aluminum foil jammed into the front boost hole. Or maybe the fairies steal it. They are kleptos.
 
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A hot enough fire will melt aluminum foil jammed into the front boost hole. Or maybe the fairies steal it. They are kleptos.
I've had foil duct tape over the boost hole on our stove for a dozen years. It doesn't get too hot there.
 
Just looked up the melting point of Aluminum. Shouldn't have been that hot. *shrug*
 
Well covering the boost hole with a magnet made all the difference.

Fire was super easy to control. Great secondary burn with nice blue flames. Best of all, it never took off on me.

I had no problem starting the fire either using the top down method with plenty of kindling on top.

I have not installed the flue probe because I was too eager to get a fire going but will in the future as I think it will be helpful.

Thank you everyone for your help. I really appreciate it.
 
Well covering the boost hole with a magnet made all the difference.

Fire was super easy to control. Great secondary burn with nice blue flames. Best of all, it never took off on me.

I had no problem starting the fire either using the top down method with plenty of kindling on top.

I have not installed the flue probe because I was too eager to get a fire going but will in the future as I think it will be helpful.

Thank you everyone for your help. I really appreciate it.
Thanks for the update. I'm glad this worked out. You'll find the flue probe much more useful for air control guidance than the stovetop temp.
 
I got a new Super LE installed at the beginning of the month and had a similar problem. I tried covering the "boost air" with a magnet but it didn't help. The second combustion would still eventually go nuclear on me even with the air intake closed to minimum. My surface thermometer located on the pipe would climb to 700 or more and stay there for way too long. I was getting worried I would break something in my brand new wood stove. I thought the issue was excessive draft since my chimney is very tall (37 ft). I called my PE dealer and asked him if he could install a damper on my wood stove pipe just to tame the draft a little. He told me he could not install this as this was against some new building regulations in my province. He told me that a damper would not be necessary anyway and that he doubted the strong draft was the issue.

Finally when I told him I was loading my firebox up to the top of the bricks he interrupted me and told me that it was the problem and that I should stop doing that. He said that the way to go with these stoves was to put 2-3 medium size logs every 5-6 hours and 1 or 2 big round logs for an overnight burn. This surprised me because everwhere I read online people seem to load the firebox as I did before, so I don't know what to think of what he said yet.

Anyway I am now trying this "add little by little" technique and so far I have to say it seems to work great. The stove still gives a lot of heat and I have a controlled burn without overheating. When I reload I wait until the logs are charred and until I see roaring flames everywhere for 5-10 minutes before cutting the air 50% and then a little more until I get a surface temperature (on the pipe) of around 450. Then it sits at that temperature for a while before slowing dropping. Interesting fact I also have a thermometer on the top of my stove and it sits at 650-700, which was the same temperature I had when I loaded my firebox completely. It seems to indicate that I was wasting a lot of heat before.

The original poster on this thread mentioned that he had the nuclear second combustion issue even when he did a small fire, so his problem seems to have another cause than mine. I just thought my experience could help others who have their Super LE burning too hot.
 
When I went with my neighbor to pick up his 27 the dealer basically said the same thing, just a couple splits at a time every few hours is a good way to run this stove. I’ve been trying to talk him into loading more wood and really see what it can do but he seems pretty satisfied just adding a few at a time and letting it burn out at night.
 
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You can close down way before everything is charred.
Well you're absolutely right and that's exactly what I just did for my last reload. When the thermometer on my single wall stove pipe reached 600 I told myself "Ok that's enough" and decreased air intake by 50%. The wood was far from being completely charred at this point.

As soon as I cut the air intake the temperature on that thermometer started going down, which never happened when I was fulling the firebox. Right now I can say I'm impressed with this stove. I just wish I could load it up fully without having the fire goes nuts but hey I guess that's just me.
 
When I went with my neighbor to pick up his 27 the dealer basically said the same thing, just a couple splits at a time every few hours is a good way to run this stove. I’ve been trying to talk him into loading more wood and really see what it can do but he seems pretty satisfied just adding a few at a time and letting it burn out at night.

Thanks for letting me know, great to hear I'm not the only one who have been told to refrain from loading the firebox completely! I'd love to hear the official take from the Pacific Energy team about the "correct" way to run the Super LE / Super 27.
 
Keep playing with it. You're on track shutting the air down early. A side benefit is getting the secondaries popping earlier is making the most of your fuel. All the volitiles that off gas early are being fully combusted now.
 
I start shutting down the air when the flames start reliably kissing the baffle and secondary action starts happening.
 
You may even be able to shut it down a little sooner. I usually start backing off at 400 with my Condar flue probe but it also depends on weather and coal bed size.
 
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You may even be able to shut it down a little sooner. I usually start backing off at 400 with my Condar flue probe but it also depends on weather and coal bed size.
If you have a flue probe I guess you have a double-wall stovepipe? I have a single-wall pipe so I think that's why the temps are higher. Honestly if I'd cut the air intake at 400 I believe the fire would start dying pretty quickly.
 
With experience you will know what the fire has to look like before it can be turned down.
 
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If you have a flue probe I guess you have a double-wall stovepipe? I have a single-wall pipe so I think that's why the temps are higher. Honestly if I'd cut the air intake at 400 I believe the fire would start dying pretty quickly.
Yes double wall with flue probe. I missed that your running single wall pipe. A 400 external temp on single wall is equivalent to 800 internal temp. 400 internal temp is equivalent to a 200 external temp. There’s also some lag time with these thermometers so the actual temps are probably a bit higher.
 
Thanks for the info!

By the way, quick update. I tried putting a little more wood on my last reload. Instead of adding 2 medium size logs, I stacked small and medium logs/splits to cover just the height of the bricks, not higher. My single-wall stove pipe temp shows 600 f with the air intake closed all the way down. I don't want to be a slave to my thermometer because the fire looks nice. No lazy flames but still it looks like a controlled fire to me. Should I be concerned about having 600f on my stove pipe?

I did the reload when the stove top temp was 350f. Perhaps the coals were still a bit too hot, I don't know.
 
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600º on single-wall = up to 1200º internal flue temperature. That's too hot. It's also a lot of wasted heat up the flue. Burn down the coal bed further by placing a couple of skinny splits on it and open up the air to 50%. Let that burn for an hour. With the next fire go ahead and start turning down the air sooner. Go by the visuals as well as the flue thermometer. Turn down the air as quickly as possible without smoldering the fire. If there are lazy flames, that's ok. The fire will regain strength and then you can turn down the air some more.
 
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600º on single-wall = up to 1200º internal flue temperature. That's too hot. It's also a lot of wasted heat up the flue. Burn down the coal bed further by placing a couple of skinny splits on it and open up the air to 50%. Let that burn for an hour. With the next fire go ahead and start turning down the air sooner. Go by the visuals as well as the flue thermometer. Turn down the air as quickly as possible without smoldering the fire. If there are lazy flames, that's ok. The fire will regain strength and then you can turn down the air some more.
Thanks for the tips! I tried that yesterday. Instead of waiting for the fire to really catch on as I was doing before, I started turning down the air really quick (I think the stove pipe temp was at 300f). The flames were just at the front and pretty small but I kept it this way just to see if the out of control second combustion issue would end up happening anyway.

It didn't, so it worked. However I am not sure if the second combustion even kicked in as I didn't see those beautiful flames shooting from the top. I guess I turned down the air a bit too fast this time. I will continue playing with the timing and hopefully I will get it right!

So far the only reliable way I found to get a hot AND controlled fire is to put less wood when reloading.
 
Try starting to turn down the air when the stove pipe temp is 400º and don't turn it down all the way, just until the flames start to get lazy. Then wait for the flames to regain strength and close it down some more until the flames get lazy again. Also, remember that the air control is not linear. Most of the control is in the last inch of movement.
 
I am not sure if the second combustion even kicked in as I didn't see those beautiful flames shooting from the top.
During the day, you can go out and look at the plume to determine how cleanly it is burning. Now, steam is released at the beginning of the load, but it has a different look than smoke, which looks darker and heavier.
I haven't run the secondary stove I have access to enough yet to understand what goes on, but I'm wondering what happens if you shove the coals to the back, where there's ash under most of the load instead of coals. Does the fire progress in a more controlled manner if it has to work its way "upstream," from back to front?
How about with a top-down fire started in the back?
I guess a lot depends on the wood you're using as well, since dense woods I use seem to catch and burn at a slower, more controlled rate.
 
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