Lazy Cat?

[Fisherman-Travis]

Hi everyone. I just installed a ke1107 into my parents poorly insulated, single pane windowed double wide mobile. The stove was purchased second hand with a two season old catalyst. I cleaned the cat and did a vinegar soak and rinsed before the install. The cat has a good amount of cracks but no missing material. The stove has now been going since Sunday evening and I’m trying to train Mom and Dad how to operate the hi tech machinery as they are used to a old non-epa stove similar to a Fischer.
Observations:
-Draft may be a little week. Hard to get the fire ripping. Flue is at least 15’ but I haven’t measured smoke comes out of the door if left open longer than 10 seconds
- catalyst seems to take a long time to ignite. After a reload the thermostat must be left on max high for 45-60 minutes to get the cat hot. Lots of smoke until it gets above 1000 degrees. Cut back to 3:30 position or a little past #2 and the smoke clears after a while and I think will maintain active but its cranking the heat out.
- I think it will cruise in active at 3 o clock position or #2 on the thermostat but slightly less such as the minimum of the “normal” silver zone on the t-stat and the cat temp will go down to the 500° zone on the edge of active thick whitish smoke starts up again which tells me it’s not actually active
- seems like anything less than 700° on the thermometer and the smoke starts up again and it falls down to 500°
Oh and the wood seems to be 15-17% average checked with a meter

Does this sound like a work out catalyst or possibly draft issue? Does the thermostat ever need to be adjusted or does this sound normal? Pictures are of settings and smoke on the verge of clearing

 

[bholler]

What is your procedure for using the meter?

 

[Fisherman-Travis]

What is your procedure for using the meter

What is your procedure for using the meter?

I re-split a split and checked what would have been the center. Standing dead madrone. I must say i am a little skeptical of those readings. The smoke is thick and white which looks like steam. Also I witnessed a little sizing with that madrone. Stove seems to run cleaner with some soft wood. Moisture Meter is a new extech brand.

 

[Woody Stover]

Can you ever see the cat glowing? At what probe temp does it start to glow?

 

[Fisherman-Travis]

Can you ever see the cat glowing? At what probe temp does it start to glow?

So the first two days I did see some glowing for a short time. Probably started seeing a slight glow around 1100 but I didn’t record that. First fire after install and cat cleaning it hit 1400 and we had the cat glowing all the way across till we closed the thermostat down some. Then it got brighter for a short time then stopped glowing. I’m starting to see that it stops working when it falls below 700. If kept there or higher it seems to be pushing out a lot of btus and I don’t think would see any sort of extended burn times in a full load. Not horrible just standard. I don’t think a 24 hour burn is going to happen with the cat staying active.

 

[Woody Stover]

Yeah, you don't know the history of the cat that came with the stove..it could be into the tail end of its lifespan. But one cheap, easy thing to try first would be to add a cheap 2' section of snap-together connector pipe from the farm store to the top of the stack temporarily to see if that would improve draft and possibly make the stove easier to run.
You could check how far the tip of the probe is from the face of the combustor, to assure you are getting accurate readings. It should be about 1/2".
Actually, I probably know more about TV reception and antennas than I do about BK stoves. 😆 I don't really watch much TV but I do enjoy the challenge of getting the tough channels. 🤓😏
I hope that antenna mast isn't fastened to the utility pole! 😬 Or close enough to the power lines where it could fall onto them..

 

[Highbeam]

Madrona is some super dense and slow to get going wood. These things smoke. I am surprised that you are getting 15' of chimney with a double wide and not at the peak. I would expect you are closer to 12'.

If the previous owner used this stove for his heat then it could be at end of life. I've only ever gotten two years out of the last several I've put through a BK when using for full time heat in the NW. Running low on softwoods would appear to be harder on a cat since all of the combustion is happening in the cat.

How's your door gasket? Cracks in the catalysts are often a symptom of thermal shock and the most common cause of that is a leaky door gasket. This would affect your thermostat settings too.

 

[Fisherman-Travis]

Madrona is some super dense and slow to get going wood. These things smoke. I am surprised that you are getting 15' of chimney with a double wide and not at the peak. I would expect you are closer to 12'.

If the previous owner used this stove for his heat then it could be at end of life. I've only ever gotten two years out of the last several I've put through a BK when using for full time heat in the NW. Running low on softwoods would appear to be harder on a cat since all of the combustion is happening in the cat.

How's your door gasket? Cracks in the catalysts are often a symptom of thermal shock and the most common cause of that is a leaky door gasket. This would affect your thermostat settings too.

door gasket is new. Also I had to replace the frame that holds the bypass gasket. Used the one that BK sells and welded it in. I think we are getting it dialed in better. I had them leave the thermostat on #2 or 3 o’clock last night and I think it stayed active all night and wasn’t terribly hot. I think what we are experiencing is a combination maybe of older cat, week draft and they have been setting the thermostat too low. With the stove running at a very medium middle of the road temp the air flapper closes 100% at a setting less than 3 o’clock. They have been trying to run it at 2:30 position at night to conserve wood and I think it’s just too low and the cat falls out of operation.
They have 20 acres of Douglas fir and redwood but buy three or more cords of hardwood every year to supplement and for longer burn times and overnight burns on their old smoke dragon and their house was always cold. I got this King for them hoping they can comfortably burn soft wood off the property only instead of purchasing hard wood. I figure I’ll get a new cat for next season and finish this one with the old one

 

[Highbeam]

door gasket is new. Also I had to replace the frame that holds the bypass gasket. Used the one that BK sells and welded it in. I think we are getting it dialed in better. I had them leave the thermostat on #2 or 3 o’clock last night and I think it stayed active all night and wasn’t terribly hot. I think what we are experiencing is a combination maybe of older cat, week draft and they have been setting the thermostat too low. With the stove running at a very medium middle of the road temp the air flapper closes 100% at a setting less than 3 o’clock. They have been trying to run it at 2:30 position at night to conserve wood and I think it’s just too low and the cat falls out of operation.
They have 20 acres of Douglas fir and redwood but buy three or more cords of hardwood every year to supplement and for longer burn times and overnight burns on their old smoke dragon and their house was always cold. I got this King for them hoping they can comfortably burn soft wood off the property only instead of purchasing hard wood. I figure I’ll get a new cat for next season and finish this one with the old one

Whoa, would love to hear more about the bypass gasket frame replacement. Mine has failed and replacement looks exceedingly difficult but I do have a couple of welders in the shop. My BK has been rock solid otherwise.

There should be no problem at all running a king overnight to keep a double wide warm in NorCal with softwood. You could do it with cottonwood. There is a big difference with small thermostat changes on these stoves. Like down to the 1/16" of an inch make a big difference. My BK is old enough that I also have numbers on my thermostat label and I use those marks for precise setting so that I don't get too hot overnight and I'm burning on 24 hour reload cycles with doug fir.

It's hard to understand the problem your parents are having. Is it too hot or too cold? If they are turning the stove down so far that the cat is stalling then it sounds like they are getting too hot. Keep that cat thermometer over 500 and it's expected that the chimney will smoke off and on.

A new cat is probably a good idea. Especially after all the work you did to replace the bypass opening, bypass gasket, door gasket, and then to leave a cracked up cat in there is a shame. It was probably used pretty hard if the bypass was melted out.

 

[Fisherman-Travis]

Whoa, would love to hear more about the bypass gasket frame replacement. Mine has failed and replacement looks exceedingly difficult but I do have a couple of welders in the shop. My BK has been rock solid otherwise.

There should be no problem at all running a king overnight to keep a double wide warm in NorCal with softwood. You could do it with cottonwood. There is a big difference with small thermostat changes on these stoves. Like down to the 1/16" of an inch make a big difference. My BK is old enough that I also have numbers on my thermostat label and I use those marks for precise setting so that I don't get too hot overnight and I'm burning on 24 hour reload cycles with doug fir.

It's hard to understand the problem your parents are having. Is it too hot or too cold? If they are turning the stove down so far that the cat is stalling then it sounds like they are getting too hot. Keep that cat thermometer over 500 and it's expected that the chimney will smoke off and on.

A new cat is probably a good idea. Especially after all the work you did to replace the bypass opening, bypass gasket, door gasket, and then to leave a cracked up cat in there is a shame. It was probably used pretty hard if the bypass was melted out.

after reading on this site too much and stopping by to check on the stove about once a day I think the problem is they were turning the thermostat a little too low. Not because it was too hot, just they were trying to get the extended burn going and not enough experience. We were assuming the stove would operate in the full range but I now realize it’s touchy and just because the dial goes to 1 doesn’t mean it will work there. Today I think we realized #2 is the minimum setting with this cat. Also seems to be the cat isn’t doing much work below 650-700 degrees. I say that because the smoke will be light or clear when it’s above that but if the thermostat gets set a slightly below 2 the cat temp creeps down and the smoke starts up again below 650°

 

[Highbeam]

after reading on this site too much and stopping by to check on the stove about once a day I think the problem is they were turning the thermostat a little too low. Not because it was too hot, just they were trying to get the extended burn going and not enough experience. We were assuming the stove would operate in the full range but I now realize it’s touchy and just because the dial goes to 1 doesn’t mean it will work there. Today I think we realized #2 is the minimum setting with this cat. Also seems to be the cat isn’t doing much work below 650-700 degrees. I say that because the smoke will be light or clear when it’s above that but if the thermostat gets set a slightly below 2 the cat temp creeps down and the smoke starts up again below 650°

As the cats wear out you lose the bottom end first. I think that’s why some people think their ten year old cat still works, it’s just that they are running hot enough that the cat need not do much to sorta work.

 

[Fisherman-Travis]

Whoa, would love to hear more about the bypass gasket frame replacement. Mine has failed and replacement looks exceedingly difficult but I do have a couple of welders in the shop. My BK has been rock solid otherwise.

The replacement gasket frame is different than the old one. It comes with a gasket installed already and fits up inside the bypass hole. Grinding the old one out was the hard part but once I figured out where the welds were it wasn’t too bad. Probably worked on it two hours. It was suggested to flip the stove upside down and I agree it would be much easier but I didn’t feel like taking the brick out and having them fall apart. I wish I took pictures of the repair. The new frame fits in the hole tight so there is not any alignment guess work. Just get the old welds ground flat so it fits. The new part is made of thin gauge stainless steel though and a little tricky to get the weld to penetrate the 1/4” steel without burning through the new part.

 

[Ashful]

A few quick notes, some of which I think you've already figured out:

1. Min setting for most of us is somewhere around 3 o'clock ± 1 hour, in the range of the #2 mark on your dial. Below that, you're likely to stall the thing, unless your wood is bone-dry and your cat brand new.

2. Low draft vs. wet wood vs. failing cat, tough diagnosis from here. But with 15 feet of pipe at normal elevation, I'd be looking at the latter two. You mention it burned well on softwood, which in addition to your observations of weight and feel, is an indicator wet wood isn't helping. A cracked cat could be a sign of the thing having some age on it, even poor habits take some time and repetition to cause serious mechanical failures.

3. If this stove is a keeper, I'd just buy a new cat now, and slam it in there. Keep this old one as a backup, or as something to use again when the new one wears out in a few years, if you end up proving the cat wasn't part of today's problem. Don't forget 30 inches (just buy 5 feet now) of 1/16" x 2" interam gasket, to tape around the thing before sliding it in.

 

[Fisherman-Travis]

A few quick notes, some of which I think you've already figured out:

1. Min setting for most of us is somewhere around 3 o'clock ± 1 hour, in the range of the #2 mark on your dial. Below that, you're likely to stall the thing, unless your wood is bone-dry and your cat brand new.

2. Low draft vs. wet wood vs. failing cat, tough diagnosis from here. But with 15 feet of pipe at normal elevation, I'd be looking at the latter two. You mention it burned well on softwood, which in addition to your observations of weight and feel, is an indicator wet wood isn't helping. A cracked cat could be a sign of the thing having some age on it, even poor habits take some time and repetition to cause serious mechanical failures.

3. If this stove is a keeper, I'd just buy a new cat now, and slam it in there. Keep this old one as a backup, or as something to use again when the new one wears out in a few years, if you end up proving the cat wasn't part of today's problem. Don't forget 30 inches (just buy 5 feet now) of 1/16" x 2" interam gasket, to tape around the thing before sliding it in.

Thanks for the response. A couple of more questions have Come to mind. It seems some of their wood has a little bit more than 20% moisture, most of it is below. If the moisture is too high is it going to damage the new catalyst or does it just not work as efficiently? Second question as far as choosing a cat, I see 16 holes per inch, 25 holes per inch and steel cats. Is there a general consensus as to which ones are best lately? The moisture was the reason I was contemplating the new cat for next season after they get a good summer on the wood pile. I believe next winter will be trying a majority of softwood( Douglas fir, redwood) My hope is and it sounds like this will be the case, we don’t have to worry about hardwood for them because we have to buy it or drive a hour inland to cut it ourselves. We have an abundance of softwood on site.

 

[Ashful]

The 25 holes/inch Steelcats are better in most ways, with one exception. They're better because they have no susceptibility to fracturing, due to thermal shock or other mechanical stresses, and because they have overall more surface area of catalyst exposed to the exhaust stream. Their only deficiency is that the smaller passages can be more prone to clogging with fly ash, but that shouldn't really be a problem for anyone running a King on 15 feet of pipe, it's more an issue for those running the BK30's on very tall pipes. So, if available, I'd go Steelcat for your 'rents.

A few splits over 20% with a load that averages under 20% is not much of an issue. Yes, it may take a bit longer to bake the water out of one wet split, but load average is really the biggest factor in how a given load will burn.

Steam impinging on a hot ceramic cat can indeed cause the sort of thermal stresses (CTE) that will cause cracking, another reason for them to go with a Steelcat, if swapping.

 

[Woody Stover]

Steam impinging on a hot ceramic cat can indeed cause the sort of thermal stresses (CTE) that will cause cracking, another reason for them to go with a Steelcat, if swapping.

Yeah, can happen, but not likely as long as you open the bypass for several minutes before loading the wood, then burn the new load in for a while before closing the bypass again...as you would normally would when running the stove.
Now if you open the door when the cat is blazing and toss in a soggy split on a blazing coal bed, then closed the door and bypass immediately, maybe you'd stress-fracture a ceramic cat.
That said, I may see a hairline crack in one of my ceramic cats, but the cat will need replacement because it's dropping off in performance, far before any cracks ever become an issue and the cat starts to crumble apart.

 

[stoveliker]

I think that thermal shock (pushing too cold gases thru a too hot cat) will also damage a steel cat. Not necessarily because the substrate (steel vs ceramic) cracks, but because the oxide coating on the metal substrate might delaminate from that substrate when too fast temperature changes occur.

Personally, I've always wondered about the steam. Clearly it's not steam ("mist") impinging on a cat, but water vapor. Water vapor can be HOT, as in much more than 100 C. So I wonder about the "steam is bad" issue. Of course, changing water liquid into water vapor eats a LOT of energy in the form of latent heat, so the gases will be cooler than if no water was present. Still, I wonder how much the steam argument is based on the temperature here. I don't have data though.

 

[GrumpyDad]

Am I the only one that sees this thread in recent and knows what it is about but still expects to see a picture of a lazy cat laying near a stove?

 

[stoveliker]

Not the only one! I thought it would have started with a pet in front of the stove (and ended with a zoo of pets in front of many stoves).

I do like such pics though. Always good to look at beings relaxing in front of a fire.

 

[moresnow]

The steel Cats can indeed fracture, distort and fail. They also require closer scrutiny for cleaning intervals. My experience.

 

[GrumpyDad]

Oh for God's sake...

 

[Ashful]

The steel Cats can indeed fracture, distort and fail. They also require closer scrutiny for cleaning intervals. My experience.

Anything is possible, but you're flying in the face of convention wisdom and experience, that fracturing due to CTE is primarily the realm of ceramic cats.

I have indeed melted a few steelcats, all the cheaper diesel foil variety (Condar), and all in pretty crappy stoves (Jotul Firelight 12's). They distort somewhere above 2600F (yes... been there), but I've never seen one crack. How is that even possible? You'd have to reach a metal fatigue threshold through numerous CTE-driven cycles seems unlikely anyone would keep a cat installed and in use after such distortion.

I don't believe the more durable durafoil cats used by BK and Woodstock are anywhere near as prone to distortion as the older and cheaper diesel foil variants used by some other companies.

 

[Fisherman-Travis]

So what are the recommended brands for either steel or ceramic for this stove. There seems to be a lot available after a quick google search. Condor, Midwest hearth and some cheap Amazon cats that are pure white ceramic. Who has the thickest or longest life coating

 

[cr0]

Yeah, can happen, but not likely as long as you open the bypass for several minutes before loading the wood, then burn the new load in for a while before closing the bypass again...as you would normally would when running the stove.

Newcomer here trying to learn. I thought you want to keep the bypass open as little as possible when cat is in the active zone. Is it damaging to the cat to run the stove with the bypass open (in which case I'd be much quicker to open and close the bypass during hot reload)? Or it's just for efficiency sake?

It sounds like a balance between two opposite needs:
- Keep the cat closed whenever the cat is in active temp zone (for efficiency? to avoid damage?)
- Open the bypass for a few minutes before and after hot reloads
but I might be misunderstanding something

 

[stoveliker]

The cat that BK would recommend is the one that comes with the original stove - they can't (legally) recommend anything else as the testing and certification happened with that OEM cat.

I have bought a MidWest Hearth cat. It's stored for when I need it, so I don't have to wait.