Blaze King Ultra Base Flex

[CaptainMauw]

I want to start by saying this is not a rag on BK, as their customer support is top notch and, frankly, despite the situation, I am beyond happy with the stove itself. So, please don't read this as such, this is merely a precaution for potential buyers on a topic that I have only found in one other location.

Brand new KE40 Ultra purchased in August, and stored in the barn until September when I got it into the house. I have an old single story farmhouse (circa 1880's-ish) with a Michigan style concrete cellar. Original beams, hardwood floor joists, 2 layers of hardwood floor, and then a brick hearth pad make up the floor of the main room. Its an old house so the main room floor does sag slightly in the middle. The BK is replacing an old VC Dutchwest XL which was actually heavier. Old VC was on parlor legs.

As with an old house, if you walk with a heavy foot, the floor does shake ever so slightly. This was never a problem with the old VC. It was rock solid on its legs and never shook. This KE40 on the Ultra pedestal is a full on bobble head by comparison. The base itself attaches near the center of the bottom of the stove, leaving quite a bit of overhang to the edges of the stove. The base is simply sheet metal that is rolled and formed and the outer edges which make up the footprint on the floor are located significantly further from the portion of the base that carries the load of the stove. That combined with the only 4 attachment points on rolled over sheet metal to the stove bottom allow significant flex.

Due to this, a certain degree of flex and wobble can be expected even if installed on the concrete floor of a barn. Whether or not this is acceptable is beyond my prerogative as that is not my environment. When installed in the aforementioned house environment, merely walking next to the stove causes what I would classify as violent shaking, given that the stove is just shy of 500lbs and something that heavy with a fire inside of it, to my opinion, should not move at all.

In an attempt to remedy the situation I did a number of things. First, underneath the base in the open space, I lined bricks that are slightly taller than the open space and are aligned with the portion of the base that takes the load of the stove. I then cut and machined angle iron brackets to serve as stiffeners for the upper portion of the base and attached the base to the stove with grade 8 hex bolts thru the angle iron, thru the base holes, and then into the stove. While this may have helped some, it did not help enough for me to feel any more comfortable. The root of the problem is that sheet metal under any significant load, will flex in both directions, and I can only manage to constrain it in a single direction. I am yet to even attempt installing the new stove pipe because double wall is too expensive to risk and the wobble is guaranteed to cause problems with it.

So, my path forward is to scrap the ultra base and opt for parlor legs with the ash pan kit. Moving the stove supports to the corners with good steel will kill any flexing and should hold the stove rock solid. And no, I am not expecting BK to fix this as it is equally on me with the environment that I am installing in. If I was on a non-supported stove hearth pad with no subfloor underneath I expect this issue would be minimized to the point of not necessarily being a problem (maybe?). I am sure that I could spend a day welding in cross supports in the base to make the Ultra base perfectly rigid, but that takes time (in the middle of harvest currently, time is a commodity more precious than gold) and isn't a guarantee, so parlor legs it is.

In conclusion, if you are planning on a BK (namely the big King) keep in mind that the ultra base will flex no matter what you do to try and constrain it. If you are installing on a supported floor of any kind, I highly recommend either of the other bases to prevent you from having the same problems or spending the extra money to remedy the problem that you never thought would exist. And again, this is not a rip on BK. Their stoves are top notch and support is unmatched. Their ultra base just leaves a bit to be desired.

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[ericm979]

There is a similar thread on ********** forums. You might join and ask the poster if he got resolution.

 

[ericm979]

I forgot how childish this forum is about others. hearth with the usual suffix.

 

[CaptainMauw]

Yeah that was the only one I found and alluded to for this issue. Knew better than to try and link it direct.

Im not too worried on a resolution as I am just opting to swap bases altogether to avoid complications given my specific circumstance. Plus with an early winter already starting, I don't have the time to mess around and fiddle with things.

 

[CaptainMauw]

Well it took way too long and two different dealers to get the parts (nearly 8 weeks) but the legs and ash pan came in and I got the stove together just in time. She is now rock solid with zero wobbly anything. Once again BK support was fantastic, but the dealer situation was....frustrating. None-the less, installed and fire up. Now I need to figure out what to do with the Ultra base.

I know they say that it is impossible to over fire these stoves, but it was still a nerve wracking morning when the cat probe pegged out to max within 15 minutes of bypass closure and then took nearly 25 minutes to come back down to a desired reading even though I had it throttled to the minimum setting. I haven't been on edge like that for a long time.

But by golly is this thing a Cadillac compared to the temperamental old VC Dutchwest. Its just going to be a few weeks of learning curve to figure out how she likes to run with this chimney setup.

 

[moresnow]

Glad to hear things are ironed out. The wildly hot Cat temps are very common with brand new Cats. Your Cat temps will mellow shortly.

 

[CaptainMauw]

Glad to hear things are ironed out. The wildly hot Cat temps are very common with brand new Cats. Your Cat temps will mellow shortly.

That jives with all the research I've done since yesterday morning. A brand new cat in the VC was similar, but never quite this wild. Im keeping the fires very small and turned down low for now to break-in the cat and keep it from any premature damage.

 

[CaseyForrest]

Here is what I have learned going on season 3 (I think) of the King....

My first fire, I followed the recommendation to a T. I too, found out I could peg the CAT by allowing the fire to run with the bypass open to bring it up to temp.

Now.... Prior to a reload which normally occurs around 6am and 6pm.... Ill turn the stat up to get the coals going which in turn helps get the cat back up to temp. Open the bypass, open the door, rake most of the coals to the front while simultaneously pushing ash to the back... Load the stove and shut the door. Make sure Ive got a good flame going and then close the bypass. Sometimes its in the active range, most of the time its not. Regardless, I leave it this way until the cat thermometer starts to climb and when it gets about 1/4 to 1/3 in the active range, bring the thermostat back to cruising position.

The only time Ive stalled the cat is when I load the stove too late and want to go to bed, so I rush turning it back down.

 

[CaseyForrest]

Oh, I also found that my particular thermostat doesn't do much below half way, or around 3 o clock. Typical cruising position for our set up is around 330 when temps are around 30 degrees. If the wind picks up and temps drop below 20, then 4-430. Anything below 10 degrees and we fire up an insert on the other end of the house.

 

[CaptainMauw]

I was pegging the cat with the bypass closed and the thermostat turned down to basically off. Thats what rattled me at first. There was no "operate at high for 30 minutes before turndown" as per the manual because the cat took off in under 5 and at the 15 minute mark was making tracks into the black part of the probe, even though T-stat was turned down as far as it could go. I can happily report that just 48hrs later and the cat has settled down quite a bit and I am starting to run the stove as desired and have much better control of the stove with the thermostat.

In browsing across multiple forums and threads it appears that there is no direct correlation of the BK cat probe reading to any specific temperature. It is basically just a dummy light to indicate if the cat is engaged. None-the-less, my flue probe was reading way hot so I know she was chugging and trying to run away on me. Some have swapped over to a Condar cat probe which is calibrated with temp readings and I will likely do the same, having come from other cat stoves, I like to know ballpark temps which helps me track and verify health of the catalyst and just overall heating comfort.

I loaded just a bit heavier this morning (though very much still a small fire) now that the cat seems a bit more settled in, and I expect this to continue over the next week or three until I get to the point of stuffing it full once everything has settled nicely.

 

[CaseyForrest]

Keep in mind the cat uses smoke as fuel. So if you get a bunch of splits burning and then turn the air down, you've gone from an active fire to a bunch of smoldering. That's why I went to closing the bypass almost immediately after a reload. I have yet to see any detriment to the cat from having smoke go through it when its inactive.

I tried one of those condor stats ... I guess it worked... but something happened to it and I put the BK stat back in. If I'm ever not sure, I lean down and physically look to see if the cat is glowing.

I did switch to a steel cat too. It does indeed light off a bit earlier over the ceramic cat.

 

[Del_]

Are air leaks leading to near runaway conditions?

 

[sean donato]

I think it's just the new cat breaking in @Del_ . I have limited experience with cat stoves but they seem to burn really hot at first then settle down after a few burn cycles.

 

[moresnow]

Oh, I also found that my particular thermostat doesn't do much below half way, or around 3 o clock. Typical cruising position for our set up is around 330 when temps are around 30 degrees. If the wind picks up and temps drop below 20, then 4-430. Anything below 10 degrees and we fire up an insert on the other end of the house.

Your low "set point" of around 330 is very much the same as my Sirocco. On the other hand, I have a couple Princess models in neighbor's places that have much lower walk away set points. All depends on the stove location and venting setup. This can be rather tough to explain to new owners!

 

[CaptainMauw]

Keep in mind the cat uses smoke as fuel. So if you get a bunch of splits burning and then turn the air down, you've gone from an active fire to a bunch of smoldering. That's why I went to closing the bypass almost immediately after a reload. I have yet to see any detriment to the cat from having smoke go through it when its inactive.

I tried one of those condor stats ... I guess it worked... but something happened to it and I put the BK stat back in. If I'm ever not sure, I lean down and physically look to see if the cat is glowing.

I did switch to a steel cat too. It does indeed light off a bit earlier over the ceramic cat.

This make sense. It is counter intuitive, and the opposite of how the old VC ran, but logically it makes sense to me. Granted, most cat stoves have primary, and secondary air; primary for the firebox, secondary for the cat. BK's only run the one. By my understanding (from what im seeing), the thermostat really doesn't control the cat per say, but rather the firebox temps, thus in turn, the cat. The cat is more effected by the thermostat when its in the lower settings and throttling the air. The medium to high settings, the cat does what it wants, but the stove body runs warmer and throws more heat.

The cat runs about the same spot on the dial whether medium-high or medium-low to low, but the stove itself runs different temps and throws different heat. Hard to explain, but maybe im making sense here. This is verified by monitoring stack temps. Mid-burn on thermostat low with the cat nice and hot, im seeing ~200F on the exterior of the double wall. Same cat temp but set to medium thermostat, and im pushing 300F on the stack (exterior of double wall). Granted, Im sure this stove is nowhere near "broken in" yet either.

I think it's just the new cat breaking in @Del_ . I have limited experience with cat stoves but they seem to burn really hot at first then settle down after a few burn cycles.

Yup. The cat is much more mellow tonight, and tonight's fire is the hottest one yet. The old VC cats were similar, but not nearly as wild as this BK one on first fire. I'm trying to slowly bake in the stove and the stove pipe which keeps tripping off the smoke alarms. Probably another hot fire or two still to complete that, I hope. But the cat is acting much more like it should now. She just needed to settle in some.

Your low "set point" of around 330 is very much the same as my Sirocco. On the other hand, I have a couple Princess models in neighbor's places that have much lower walk away set points. All depends on the stove location and venting setup. This can be rather tough to explain to new owners!

Probably why BK took the numbers off the thermostat dial that used to be on there back when. Position is all subjective to a given unique setup/environment