Kuma sequoia review

[sweedish]

Ok, Saturday I finally got my Kuma installed, and I will be periodically posting with my thoughts on it, and I may have some general questions, this is my first house, and my first insert, I am not a complete stranger to burning, my dad has an owb.

I have a bilevel house, and the insert is downstairs, 25’ 12” by 12” clay chimney, put a double walled stainless liner down it, was still quite a tight fit.

My first fire was the customary burning of the crate the stove arrived on, and some small pine branches, cat probe read 950.

I did load the insert last night around 930, mostly white/scotch pine, ran about 1/3 air open, watched the stove temp, again around 950, till 11, went to bed, around 7 checked the fire, cold coals.

Anyone have much luck with getting an all nighter with pine? Or am I asking too much?

What cat probe temp should I reload at? And what’s a temp to shoot for for an extended burn?

Currently, there is a 40mph wind, my house is on a hill surrounded by trees also, I’m getting backdraft/smoke in the room from the secondary air inlet, I have an outside air inlet for the primary. I think I need a wind deflector cap.

 

[Woody Stover]

Very cool, Sweed, we like to read about stoves that we haven't gotten a ton of feedback on. It'll be interesting to hear how it heats the big bi-level.
Ah, yes, the burning of the crate. Mine was...uh, I forget, Tamarack, Hemlock...some kind of soft wood.
Can you measure the actual loadable volume of the fire box, when the stove is cold sometime? If it's anywhere near the advertised 3.6, you should pretty easily get a solid overnight burn, even on Pine. You'll have to see how soon you can close the bypass when firing a fresh load; The quicker you can close it, the less of the load you burn getting the stove to light-off temp. Flue temps will provide the most immediate feedback as to what's happening in the box. You may not be able to shoot the flue with an IR temp gun if you have a surround on the stove, but maybe you can shoot the stove top through the blower vents?
1/3 open air seems like a lot, once you have the cat lit and are cruising the stove. If it's not real cold out and I'm running a cat-only burn, no flame, I typically have the air open about .5 on a scale of 4, or about 12%.
I go by stove top temp or the size of the coal bed, as far as re-loading the stove. If I have a decent amount of coals, I can open the air up a bit and keep the stove top at 300 or 350, depending on how much it had cooled before that. That's enough to hold room temp for a couple more hours. Of course you have a different stove and are heating a much bigger area, so YMMV.
I looked at your manual, but don't see the details on the secondary air vent. Does that feed the cat?
We like pics. For one thing, can you post pics of the door latch assembly?

 

[Woody Stover]

How big were the Pine splits you loaded last night? If your it's dry, load it with bigger splits to slow the fast-burning Pine down a bit. You might need to have a bit of flame in the box to get more heat than a cat-only burn provides. Then you won't get the 14-hr. max burn time, which won't apply in mid-state Michigan anyway. If that is Sugar (hard) Maple, it will extend burn time considerably, over the Pine.

 

[sweedish]

This is an insert, so I can’t give a flue temp, generally if the round is bigger than my hand I split it. I have an temp gun, I’m just about to load for the night, cat probe (condor watchman) reads 600, stove top 516f. Through the vents. But I have the blower attached and running. Maybe I ran it a bit too open last night, and I did not cram it super full since I had some uglies in it, have to be more careful cutting I guess.

I thought I would be getting a higher temp, even air open full I only got a 1050 max cat probe temp. I’m going to try some hardwood for the reload.

 

[sweedish]

I’ve just loaded with oak 2 by 3”s from an old frame I cut, and a few maple rounds, the bench frame I’m sure is dry, being in a garage for years

 

[Woody Stover]

I thought I would be getting a higher temp, even air open full I only got a 1050 max cat probe temp. I’m going to try some hardwood for the reload.

If you are running flame in the box, that will burn some of the smoke and the cat won't get as hot. Flame will heat up the sides of the box more, though. Are the sides of the stove covered by part of the blower convection chamber?

 

[sweedish]

Yes they are, with reading about how some people overfire, I’m not sure how one could with this insert unless I burn magnesium in it. Currently my cat probe is holding steady at 800 and I’m at about 15% air open, I do wish that Kuma had pre notched the air control rod, I may take a saw file and do that. For now I’m off to bed.

 

[Woody Stover]

Currently my cat probe is holding steady at 800 and I’m at about 15% air open, I do wish that Kuma had pre notched the air control rod, I may take a saw file and do that. For now I’m off to bed.

Unless your wood is down to about 18% or less, measured on a fresh face, re-split at room temp, moisture above that will take some temp off the cat and your stove. I considered 1200 cat probe on the Buck 91 to be just about perfect. That's going to depend on other factors also, such as how far the tip of the probe is from the face of the cat etc. on your particular stove. Cat could be just as hot at 800. Can you see the cat glowing, looking up through the glass or in around the bypass rod? I got to where I could just about guess what that cat probe would be reading by how bright the cat was glowing.
You could just mark the rod with some white nail polish...that way you can change the marks later, when your wood is drier.

 

[sweedish]

Probably the wood may not be fantastically dry, standing dead cut within the month, and I’ll take some pics of it later

 

[John B]

I have the same stove, installed earlier this year. I had to add a damper to my install to get the most heat output, but my chimney drafts like a freight train.

I find 12 hours burns are pretty easy with this unit. I normally burn with the air only opened like 1/4" from being totally closed and I have also choked down the air intake port on my outside air kit to just a slit. Pipe damper shut as well.

My cat temps tend to cruise between 950-1150 at full bore and I dont usually reload until cat temp is 400-450.

 

[Woody Stover]

12 hours burns are pretty easy with this unit. I normally burn with the air only opened like 1/4" from being totally closed...cat temps tend to cruise between 950-1150 at full bore and I dont usually reload until cat temp is 400-450.

The Buck 91 had air wash and another air channel half way back across the inside of the top. I left that open about 1/4". It also had doghouse "shotgun" air feeding in at the bottom center of the door opening, which I closed once the stove was cruising. Stove was down to 250 or so after 12 hrs, but the box was a trapezoid and a little under 3 cu.ft. of usable space. I think the Sequoia may have a larger, more square box...? I had 21' of liner, no damper, and my MIL's house and the stove sold before I figured out how to have as much control of the air as I wanted.

 

[sweedish]

I have the same stove, installed earlier this year. I had to add a damper to my install to get the most heat output, but my chimney drafts like a freight train.

I find 12 hours burns are pretty easy with this unit. I normally burn with the air only opened like 1/4" from being totally closed and I have also choked down the air intake port on my outside air kit to just a slit. Pipe damper shut as well.

My cat temps tend to cruise between 950-1150 at full bore and I dont usually reload until cat temp is 400-450.

I am getting similar highs at full bore, how tall is your chimney?

 

[sweedish]

I am getting similar highs at full bore, how tall is your chimney?

So your had to cut the intake? I really don’t want to pull the insert out anytime soon

 

[Woody Stover]

Probably the wood may not be fantastically dry, standing dead cut within the month, and I’ll take some pics of it later

If that's the dead Maple you were talking about in your other thread, where you got a reading of 17.5%, that's very good. However, even though you got that on a split or two doesn't mean all the wood from that tree is that dry.
As far as your draft, you may have to take measures to tame it down, at 25'. I know you'd rather not pull the stove right now, but the best solution eventually might be to put a damper just above the flue collar and then run a rod through the surround to actuate it. Not sure without seeing it if that would work in your case or not. In the meantime, maybe blocking the intake would be easier to do now. It's preferable to control the draft at a point after the firebox, though...

 

[sweedish]

How much did you cut the 4” intake down to? 1/2, 2/3 rd?

 

[weatherguy]

Someone with a Sequoia managed to better control his burn by rigging something up to his air intake, if you searched kuma sequoia titles you might find it.

 

[sweedish]

I’ve cut the air intake by a 3rd, and have it on low, had a fire about a half hour now, Full load of pine and maple. Probe reading 800.

I reloaded this morning at 930 ish with pine, back around 6 and hardly and coals, set on low while I was away.

The overnight fire was set on low, rechecked this morning around 830 ish, still just coals, had more than the previous nights. Asked the wife who got up at 4 if she noticed if the blower was running when she left at 530, she said no.

 

[sweedish]

At least tonight it’s not backdrafting, so that’s a plus.

 

[sweedish]

Sorry, cut it the air to a 3rd, re checked the wood I have in the house, pine is 21.5%, maple 17.5%, so the same abouts.

 

[John B]

I cut my air intake down to a small slit. My chimney is masonry, about 27', straight shot up.

 

[Woody Stover]

At least tonight it’s not backdrafting, so that’s a plus.

That may have been due to the wind you described in your location on the hill with the trees nearby. I don't know a lot about it but I think the OAK could cause a problem in some cases, like if it is on the downwind side of the house, or if the OAK intake is above the floor of the stove. Why did you add the OAK...is the house very tight, where the stove would be competing for air with bathroom vent fans, range hoods or a furnace?

 

[sweedish]

The house is not super airtight, the oak feeds from the attached garage, so wind should not really effect the intake side of things. And it is lower than the stove. I did it to error on the side of caution, rather not be pulling air from unwanted sources inside the house. As far as other air sources, My other heat source is electric baseboard heat, last electric bill the average temp was 2 degrees, and was $775. That was after I had redone the door seals, LED lights, and 10” of blown in in the attic on top of the bats, so working properly this stove should have a quick payback time.

I was doing paperwork today so I had some time to fiddle with the insert. And started keeping a little record,

I did block air intake by 75% at the start of this experiment

The gist of today’s results were with a full load of pine, a reload, running wide open, I get a cat probe temp of 1100-1200 degrees, from 500 degree cat probe temp on the upside to 500 degrees on the downward I’m averaging a 2.5 hr burn time, did that twice both with pine. Similar full loads.

Cut the secondary to half, and got a 5 hr burn, cat peak 950. Again with pine, similar sized load as the previous.

1030 Reloaded with maple, box stuffed extra fell, as in take a pic and brag about it full, cat probe peaked at 850, secondary air cut to a quarter, then lowest setting. Post results tomorrow.

 

[SequoiaFarm]

I'm going to go out on a limb here and guess that you need to install a damper. When I talked with Kuma about my free standing Sequoia they made sure to tell me to get a damper since my chimney is 25ft straight shot up. You can always call out there and get somebody on the line who actually builds them and who actually heats with one. I believe either Tim or Jason use a Sequoia to heat their house.

 

[Woody Stover]

re checked the wood I have in the house, pine is 21.5%, maple 17.5%, so the same abouts.

To get as accurate as possible, you need a large split or round, at room temp for a day, then re-split and test on a fresh face, away from the ends. Testing cold wood, or not on a freshly-exposed face, will give a false low reading.
That said, the fact that your cat is at least getting somewhat hot indicates that your wood isn't super-wet...
QUOTE="John B, post: 2346807, member: 23662"]I find 12 hours burns are pretty easy with this unit. I normally burn with the air only opened like 1/4" from being totally closed and I have also choked down the air intake port on my outside air kit to just a slit. Pipe damper shut as well.
My cat temps tend to cruise between 950-1150 at full bore and I dont usually reload until cat temp is 400-450.[/QUOTE]So you are getting 950-1150 with the air at 1/4" open, right?
The fact that sweedish has to have the air wide open to get similar cat temps is telling me that your wood is drier than his. And as I mentioned, any flame in the box will eat some of the smoke, and he'll get lower cat temp than you do by smoldering the load. He may not be able to smolder damp wood without risking a cat stall, he might need to run a little flame until he gets drier wood to feed it.

a full load of pine, a reload, running wide open, I get a cat probe temp of 1100-1200 degrees, averaging a 2.5 hr burn time, did that twice both with pine. Similar full loads.
Cut the secondary to half, and got a 5 hr burn, cat peak 950. Again with pine, similar sized load as the previous.

I guess you are talking primary air setting...I don't see any separate secondary (cat) air control in the pics.

Reloaded with maple, box stuffed extra fell, as in take a pic and brag about it full, cat probe peaked at 850, secondary air cut to a quarter, then lowest setting. Post results tomorrow.

If your wood is a little damp, the cat probe might go higher a little later in the burn, as the load dries out more and the wood starts gassing better.
You might be tempted to run the stove at higher air settings, in an attempt to get more heat from damp wood, to heat a 3000 sq.ft. space in Michigan.
But be careful that you're not causing "flame impingement" damage to the face of the cat. Look in the box when you have the air on a high setting. Does it look like flame is getting sucked past the flame shield and into the cat?
From your manual:
"Properly operated, the catalytic combustor in your new Kuma Stove will provide years of trouble free use. Over firing of the catalytic combustor is a common cause of failure. Try to avoid direct flame contact with the catalytic combustor. Each chimney will provide a different level of draft. For your first few fires, watch the flames as the lick up near the baffle assembly. If your chimney provides enough draft to pull the flames into the combustor, lower the amount of air by pushing the air control in towards the stove. If flames are still pulled into the combustor, a damper may be installed in the pipe to help further regulate draft."
It looks like the flame shield may be very close to the cat, judging from this diagram, so flame impingement could be an issue.
I'm also curious about how part #7 works, "baffle bypass gasket." The Buck was constructed a bit differently, and didn't have a gasket there...

On the Buck, flame wasn't hitting the cat but cat temp could still go too high with too much air, pushing 1800. Temps of 1500 or less will prolong the life of the cat. But I haven't seen any reports from Sequoia owners about high cat temps...

I'm going to go out on a limb here and guess that you need to install a damper. When I talked with Kuma about my free standing Sequoia they made sure to tell me to get a damper since my chimney is 25ft straight shot up.

The reason to install a pipe damper to control draft, as they suggest, is that it works better than the band-aid solution of blocking off the air entering the stove with tape. The box of the stove is still subjected to high draft, and will pull additional air past gaskets and other areas in the box. Only with a damper past the box will you get closer to the draft they designed the stove to work with. Some guys even put it two dampers on tall chimneys but sweed doesn't have room to do that with an insert...he might try blocking the holes in the stock damper plate, to provide more control with a single damper.

 

[Woody Stover]

Also, avoid "thermal shock" to the cat: Open the bypass and let the cat cool down for several minutes, before opening the load door.