Super 27 running very hot

[alber197]

Hi Everyone, I'm a new owner of a Super 27 wood stove that I have had for about a month. Recently, it has been running super hot and hard to turn down. When we start a fire, we start turning down when the stove top temp is around 300-350. It burns good for a little while (hour or so) then takes off and gets up to 600-700 stove top temp with the air intake turned all the way down. Then, when it gets down to coals, we add a couple (2-3) of splits, let them char and then immediately turn it down. It burns well for a while and then takes off and burns hot again. We are burning what I would consider smal fire of just 3-4 splits.

I've read about people covering the air intake with a magnet but I'm wondering if there is anything I'm doing wrong.

Air temp out side is around 15 F. Wood is 16-18" splits of well seasoned hard maple and elm. Chimney height is around 14ft from stove top.

I'm concerned about it getting worse when it gets colder and the draft increases. (it will get -20F here pretty consistently and sometimes colder).

Thank you for your help.

 

[alber197]

After doing some more research on here. I don't think the short chimney height of 14ft would create an excessive draft..but I'm still struggling to determine why the secondary burn is taking off so much about an hour after it is turned down

Tonight, I let the coals burn to the point where the stove top temp was at 250 and we needed heat. I raked them forward and put 4 large hard maple splits in packed tightly together. I watched the fire and turned down gradually over about 10-15min. Once turned all the way down, there was a nice fire going with a lazy blue orange flame and stove top temp was hovering around 450-500.

After about an hour, the stove started popping and clicking (it has done this everytime it took off) and the secondary burn went crazy again. Fire changed, got bigger, hotter and more yellow and stove temp started climbing fast.

The 4 large hard maple splits won't burn for longer than few hours and I'm back to square one.

Any suggestions? Also I've read about bending the plate for the air control. Anyone have any pictures or know of a thread with pictures for this?

Thank you.

 

[alber197]

Can anyone help with this? I've been up and down this forum. We tried larger splits and packing them tightly. Turns down real nice and then about an hour after turning down the secondary burn goes nuts.

 

[stoveliker]

@begreen?

I know it's a busy time.

 

[EatenByLimestone]

The super is a very easy breathing stove. I dont think you should be having control ability issues with a 14 foot stack.

Have you tried the dollar bill test on the door gasket?

 

[EatenByLimestone]

What thermometer are you using and where is it placed?

 

[alber197]

I did do the dollar bill test, the gasket is sealed well. I checked the ash dump also and it is not open.

I have a stove top magnetic thermometer in the center of the stove an inch or two in front of the stove pipe. I know it's not super accurate. I did order a condor probe temp for the double wall pipe.

I'm not as much worried about over firing but I'm having a hard time controlling it and it heats up the room really hot. It turns down nice and goes good for about an hour. Then the secondary burn really starts going nice and shortly after that it just takes off and gets super hot. It is turned all the way down at this point so I can't slow it down.

There's got to be something I'm doing wrong, turning down too quick or not waiting long enough. The wood is very dry and seasoned well.

What stove top or internal flue Temps should I be looking for before turning down?

Thank you.

 

[EatenByLimestone]

I have the same firebox as you with the T5. To me,it sounds like you're not turning down fast enough. Once the fire starts to lick the baffle, turn the air down bit, maybe 10-15%, once the fire builds up again to licking the baffle, do it again. If the flame stalls out, back off on the damper and get the fire burning again. Then start working the air back down again. You can do it all by sight, not using a thermometer.

I can keep a stovetop at 350 for an entire burn cycle off a reload. If its a cold start, lower than that.

 

[bholler]

600 to 700 really isn't to hot. It's getting to the top end but definitely not over

 

[Split]

I have a PE Classic which is essentially the same stove. Mine burns hot as well. My flue Temps burn at 900° and can get up to 1100°. I've plugged the air intake under the stove (the welded hole) and it definitely calms it down a bit but then I don't find it burns as it should. I've been told a little steel wool in the intake hole calms down the draft too. I'm still experimenting. My chimney is tall.

 

[alber197]

Thank you for the replys..I'll try turning down sooner.

My concern is that it's hitting the top end and the firebox is not even close to full.

I too do not think it's burning as it should. I thought there would be a little more control.

Would plugging the welded hole (I think some have called it the boost inlet) do anything for me with a short chimney or is that only to control a heavy draft? There is a second hole on my stove next to the air inlet plate that is wide open. Is that to prevent turning the stove down all the way? Could that hole be partially blocked with a magnet?

Thank you.

 

[alber197]

It's also going through wood fairly quickly. I thought I could get longer than 2 hour burn time with nice hard maple splits on low.

 

[EatenByLimestone]

Plugging the wide open hole in front does some, but the most I saw it do was make the stove a bit more sensitive. My chimney is taller than yours and it did not do much. I unplugged the hole.

Try turning the stove down when the flame starts hitting the top.

 

[alber197]

Tonight, I let the stove cool to about 250 stove top temp while allowing the coals to burn down (which is more than i would prefer since its about 5 degrees outside). After that, I loaded the firebox and turned down quicker than I had in the past in gradual increments. All that seemed to do was delay the secondary burn. But once the secondary burn got going, the stove got super hot again. The air inlet is turned down all the way and there is no way to slow it down.

The only other options I see are to build a smaller fire more often or let the coals go down to almost out and allow the stove to cool further. Both of which seem to defeat the purpose of the extended burn time and would create wild swings in temperature in the home.

I understand the EPA regulations but there doesn't seem to be much point to buying a non cat stove if you can't control it. I'm sure it is operator error somewhere but they sure seem to make it difficult.

Thanks again to everyone who replied. I'll keep experimenting to see if I can get it dialed in better.

 

[EatenByLimestone]

Could you explain your chimney in detail? Size, masonry or metal, brand, pipe from stove to chimney, lengths of sections, straight up and through the roof or through a wall.

What stove did you burn before this one?

Tell me about your wood. How long ago was it cut, split, stacked, where was it stacked, and have you tested it’s moisture?

 

[alber197]

We have 6 ft of double wall excel stove pipe off the top of the stove with (2) 45 offsets to get around the roof rafter. 8ft of straight excel class a chimney through the attic and out the roof. We were concerned about the short chimney and that is one of the main reasons we didn't buy a cat stove.

Wood is hard maple mixed with some elm. Split about 14 months ago. The elm was standing dead, gray with all the bark off. We mix birch in sometimes too. It is stored in a nice covered wood shed, elevated off the ground with air flow on all sides. It gets a lot of sun and wind off the lake so it drys nicely. We routinely check the moisture with a reader. It is 8-15% when split in half.

We had an old smoke dragon at our previous place with a damper and air inlet so very different..

It is worse with a full load of maple but regardless it always takes off when the secondary burn kicks in and stove top gets to 700. The full load is burned to coals in just 2 hours with the air inlet all the way down. Closing the air inlet down quicker just seems to delay getting to that point as quickly. The maple produces a lot of coals and we try to let them burn down as much as possible or add small birch splits to help with that.

I know we have a really great stove. As I mentioned before, I'm sure it's operator error but it seems like there is just too much air coming into the stove when air inlet is turned all the way down. I knew we wouldn't have the same control and burn times as a cat stove but thought it would be a little better than it is..

Thank you for your help..

 

[EatenByLimestone]

On the lake… are you getting a lot of wind?

 

[alber197]

We do sometimes, we can get 10-20 mph sustained with 25-30 mph gusts. I have tried to keep an eye on what it is doing relative to the wind and it doesn't seem to matter.

Almost no wind this morning, we let it cool quite a bit to the point where the furnace kicked on (stove top temp was 150, much less coals than normal). We did a slightly smaller fire with mixed hardwood but packed tightly. We turned down quickly to the point where we had to turn it back up slightly and it's roaring on the secondary burn as we speak. Stove top temp is 650 and climbing. We started the fire an hour and half ago.

 

[alber197]

Would the optional blower fan help with this? Or would it just cool the stove down faster?

There must be some sort regulation with the secondary burn because it always hits that 650-700 stove top tempand then starts to drop from there. This is regardless of wood type or medium vs large fire.

 

[EatenByLimestone]

I think they do have the EBT system on the Super now. @begreen, can you add any experience with the EBT?

 

[alber197]

I just read @begreen post about starting a fire with the step by step documentation of stove top and flue temperatures. That was really helpful, not sure how I missed that before..

As some had mentioned, 700 stove is not too hot. I guess I'm concerned about it running away on me when it gets much colder and I've got a jam packed firebox. Right now, I'm hitting that temp with a 3/4 full fire box.

I really need to get a probe into the flue and measure that temperature to get a better idea of where I'm at and experiment more.

I think the hard maple may be producing too many coals and contributing to the very fast rising temperatures also.

 

[begreen]

Sorry missed this thread. It sounds like you are working things out. With 14 ft of flue there should not be a need for tweaking. It's unlikely that the draft is an issue. It's a guess, but it sounds like the EBT is opening up as the wood starts outgassing more strongly. The EBT works like a small barometric damper on the secondary air supply. It feeds more air to the secondaries as the draft increases due to the hotter fire. This assures more complete combustion at the outgassing phase of the burn. Then it closes down, to help extend the burn afterward.

Filling the stove full may actually help slow things down, especially if the stove is packed tightly. Another thing to try is loading the stove E/W. That slows down the air by creating a blockade of wood. If you have a magnet, you could put it over the welded boost air hole to see if that helps. Do things systematically, trying one change at a time.

 

[alber197]

Thank you for your help. I'll keep experimenting.

My splits are a little large for E/W loading in the super (about 18") but ill try packing the stove a little tighter N/S.

 

[begreen]

The bloom you are seeing is not that uncommon. Tonight I reloaded a few thick splits on hot coals. The fire took off quickly with the air control wide open. After about 5 minutes I turned the air down to maybe 90% closed. The flue temp dropped down from around 700º to around 450º after a few minutes but then, after another 10 minutes, it was on the rise again as the wood became fully heated and started outgassing. The fire took the flue temp up to 675 within another 5 minutes. Now an hour later it is reading 577º with a 550º stove top.

 

[alber197]

Thanks for the info. Tonight, we let the coals burn down more than we had previously before we reloaded. We also packed the stove pretty tight and it certainly made a difference. We have been able to turn it down over about 50 min vs 5.

One question, does the welded hole (boost port) serve any purpose for the secondary burn or is it just for starting?