2018-19 Blaze King Performance Thread Part 2 (Everything BK)

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
Status
Not open for further replies.
One man’s “glaze in the lower corners” is another man’s black glass. I burn low and slow almost all the time with pitchy evergreens and have never not been able to see the fire. Just some glaze in the lower corners!
 
One man’s “glaze in the lower corners” is another man’s black glass. I burn low and slow almost all the time with pitchy evergreens and have never not been able to see the fire. Just some glaze in the lower corners!

True. To me:

Glaze = translucent brown
Black glass = opaque
 
Do people really wake up in the night to reload there stoves?
I will if i don’t want the furnace to kick on, but only when its below about -30*C. Otherwise i can get through the night no problem with enough heat.
 
I will if i don’t want the furnace to kick on, but only when its below about -30*C. Otherwise i can get through the night no problem with enough heat.

If it hit minus 30 more than once, deg C or F, I’d be moving. Holy crap, that’s too cold.

When you need to put an electric blanket over your car’s engine in winter, that’s a bad neighborhood. [emoji3]
 
  • Like
Reactions: Alpine1
If it hit minus 30 more than once, deg C or F, I’d be moving. Holy crap, that’s too cold.

When you need to put an electric blanket over your car’s engine in winter, that’s a bad neighborhood. [emoji3]
We're gearing up for just this kind of cold snap. Arctic air moving in tonight overnight and persisting through to next week. And I plug my truck in every night during the winter!
 
After a few futile searches I figure I'll just ask. How do you tell if a cat is bad? I have a Princess, manufactured in 2006. I bought it used in 2016 and I'm in my 3rd burning season. Usually light it up in Oct and burn constant through March. Burn red and white fir and lodgepole and maybe use 1/2 cord month. When it gets 20 deg and below I usually get a minimum of 12-14 hour burn. Cat seems to light off, glow properly and stays active through the burn. I have done the vinegar clean twice. The cat does have a crack in the center but seems stable and is not crumbling. Just curious as I've put around 11k hours and I'm not sure how much the PO used it (it was like new).

Second question is burn time. I've read that burn times decrease when a cat is failing. Is this because the air has to be increased or does a cat really effect burn times? I'm trying to understand how if a cat is not plugged how a failure can reduce burn times. Sorry if this has been covered before. So far I'm very happy with the stove. Saves me a fortune in propane.
 
After a few futile searches I figure I'll just ask. How do you tell if a cat is bad?
Unless it experiences mechanical failure (fracturing to the point where it falls apart), or is poisoned by burning chemicals, they usually don’t just “go bad”. They more generally fade, so slowly that the owner really has a tough time making that judgement call on when it’s time for replacement.

Generally, the first thing I notice is that it’s falling out of active region sooner than it had previously. The second thing you’ll notice is they’re a little slower to light off, but this is always the lesser indicator for me. Remember, a combustor can remain active when the fuel feed rate is lower than would normally support secondary combustion, once it has successfully lit off.

Others note the amount of smoke out their chimney, but I’ve never really paid much attention to that, myself.

I have a Princess, manufactured in 2006. I bought it used in 2016 and I'm in my 3rd burning season.
I’m not sure the age of your combustor, but I’ve settled into replacing every 3 years. I could stretch them longer, if I needed to, but the performance gains by switching out after 3 years are so substantial that I don’t have any desire to run one longer than that. I’m burning 3 - 6 cords per year per stove.

One thing you’ll see as a common recurring theme here, is how many posters replace their combustor and then say, “I can‘t believe how much better the new one is, I’ll never wait that long to swap, ever again.”

Second question is burn time. I've read that burn times decrease when a cat is failing. Is this because the air has to be increased or does a cat really effect burn times?
The amount of volatiles coming off of the wood to keep that combustor active varies throughout the burn, peaking in the first few hours, and then waning over the course of the next several hours. The ability of a combustor to remain active during that waning period is affected by the age of the combustor. Also, those pushing for extremely low burn rates (our fellow BK burners) may starve the cat for fuel, with a new cat having a much better ability to stay active under these conditions.

A failing cat does not directly decrease burn times, but an effort to keep it active (and thus producing acceptable heat) may have their owners increasing the burn rate, which does result in shorter burn times. A secondary burn stove, maybe especially the catalytic variety, exhibit a quantum drop in efficiency when the secondary system falls out of combustion.
 
  • Like
Reactions: rwhite
Unless it experiences mechanical failure (fracturing to the point where it falls apart), or is poisoned by burning chemicals, they usually don’t just “go bad”. They more generally fade, so slowly that the owner really has a tough time making that judgement call on when it’s time for replacement.

Generally, the first thing I notice is that it’s falling out of active region sooner than it had previously. The second thing you’ll notice is they’re a little slower to light off, but this is always the lesser indicator for me. Remember, a combustor can remain active when the fuel feed rate is lower than would normally support secondary combustion, once it has successfully lit off.

Others note the amount of smoke out their chimney, but I’ve never really paid much attention to that, myself.


I’m not sure the age of your combustor, but I’ve settled into replacing every 3 years. I could stretch them longer, if I needed to, but the performance gains by switching out after 3 years are so substantial that I don’t have any desire to run one longer than that. I’m burning 3 - 6 cords per year per stove.

One thing you’ll see as a common recurring theme here, is how many posters replace their combustor and then say, “I can‘t believe how much better the new one is, I’ll never wait that long to swap, ever again.”


The amount of volatiles coming off of the wood to keep that combustor active varies throughout the burn, peaking in the first few hours, and then waning over the course of the next several hours. The ability of a combustor to remain active during that waning period is affected by the age of the combustor. Also, those pushing for extremely low burn rates (our fellow BK burners) may starve the cat for fuel, with a new cat having a much better ability to stay active under these conditions.

A failing cat does not directly decrease burn times, but an effort to keep it active (and thus producing acceptable heat) may have their owners increasing the burn rate, which does result in shorter burn times. A secondary burn stove, maybe especially the catalytic variety, exhibit a quantum drop in efficiency when the secondary system falls out of combustion.
Thanks for the info. I'll probably ride this one out for this season and get a new one for next year. I usually run it st the 2 setting (3:00) any lower and the cat does stall. The #2 setting seems to keep my 1800 sqft ranch at 74 in the living room and high 60s in the far bedrooms.
 
True. To me:

Glaze = translucent brown
Black glass = opaque

Well my wood is not optimal. On cold starts it takes a while to get going and on reloads on coals it takes forever. It’s around 20-21% MC but it’s the best I have. NIELS do not exist around me either. The only other option is to try to source better firewood when buying it or use eco logs which aren’t cheap to run daily. I’m going to really clean the glass and see if I can keep the wood in the back.

My only problem is due to my small split sizes, the Ashford 25 eats wood pretty quickly. If I set it on low, it doesn’t produce any noticeable warm heat. So normally I have to put it on medium and the fan on medium. This gets me about 4-5 hours of useable heat.


Sent from my iPhone using Tapatalk
 
Well my wood is not optimal. On cold starts it takes a while to get going and on reloads on coals it takes forever. It’s around 20-21% MC but it’s the best I have. NIELS do not exist around me either. The only other option is to try to source better firewood when buying it or use eco logs which aren’t cheap to run daily. I’m going to really clean the glass and see if I can keep the wood in the back.

My only problem is due to my small split sizes, the Ashford 25 eats wood pretty quickly. If I set it on low, it doesn’t produce any noticeable warm heat. So normally I have to put it on medium and the fan on medium. This gets me about 4-5 hours of useable heat.

20% mc and 4 hour burns on medium? There is something else going on there, that's not even close to right.
 
A failing cat does not directly decrease burn times, but an effort to keep it active (and thus producing acceptable heat) may have their owners increasing the burn rate, which does result in shorter burn times.

Ah but this happens automatically, the thermostat does this without asking. Your cat is the major source of heat for the stove, the cat doing it's combustion thing makes it hot and that heats the stove. When the cat is dying it is less able to make that heat and so the stove cools. The thermostat picks up on this and sends more air into the fire in an effort to maintain the desired stove temperature which burns wood faster.

So yes, the failing cat does directly and automatically decrease burn times for a particular desired heat output and stat setting. When my cats have died it is gradual at first and then rapid near the end of life. Near the end this decline is so bad that you will find that you need to actually turn the thermostat up just to keep the house warm. Not sure why that is but it is.

Get a new cat ordered. Have it ready since you have personally hit the expected life in hours on top of whatever the previous owner did. It will not get old waiting and new cats are doubtfully getting any cheaper!
 
Well what’s considered total burn time? Like cold stove to cold stove or cold stove to coals “useable heat” ?


Sent from my iPhone using Tapatalk

Any times I quote don't have 'cold stove' on either side of 'em, I burn 24x7. Loading wood onto coals in a hot stove, :)

The definition is highly subjective. A lot of people here use 'cat active', or >500°F in the firebox. There is no actual standard as to what people or vendors mean by burn time, though.
 
Well what’s considered total burn time? Like cold stove to cold stove or cold stove to coals “useable heat” ?


Sent from my iPhone using Tapatalk

Cat active time.

Also remember that the ashford 25 is a different animal than the freestanding stove. So far I am not impressed with the reported burn times. They seem more built for show. Still, 4 hours is very low for any stove. A "medium" setting is pretty high and with blowers running that's a lot of heat output.
 
Any times I quote don't have 'cold stove' on either side of 'em, I burn 24x7. Loading wood onto coals in a hot stove, :)

The definition is highly subjective. A lot of people here use 'cat active', or >500°F in the firebox. There is no actual standard as to what people or vendors mean by burn time, though.

I’m doing something wrong or my wood is terrible. My cat only stays active if the box is stuffed and blazing. Once it burns down it falls out of active zone quickly.


Sent from my iPhone using Tapatalk
 
You're lucky you had faucets to drip! (Begin Monty Python skit here...) We used a galvanized pail to smash the ice in the well to get a bucket of water to wash with!

Ah, but of course we had it tough. We used to live under a flat rock at the north pole. We had to get up every morning, clean the rock, fight the polar bears to get our leaky bucket back, and carry the bucket ten miles up the glacier and back, fighting bears both ways, to the only spot where there was a black rock to melt the snow in the bucket. Any of us who hadn't been eaten by bears brought the bucket home, where our old dad would beat us with an icicle if the bucket wasn't full...


 
  • Like
Reactions: Ashful
I’m doing something wrong or my wood is terrible. My cat only stays active if the box is stuffed and blazing. Once it burns down it falls out of active zone quickly.


Sent from my iPhone using Tapatalk

When you turn it to low how low are we talking here?


Lopi Rockport
Blaze King Ashford 25
 
I’m doing something wrong or my wood is terrible. My cat only stays active if the box is stuffed and blazing. Once it burns down it falls out of active zone quickly.


Sent from my iPhone using Tapatalk

The blowers cause a false reading on the cat probe. Turn them off for 10 minutes before checking.

You have something else going on too. Having to turn a bk up to medium to get heat, with 20% mc wood?

Either your wood is way wetter or some other problem exists.

Let some wood warm up to room temp, then split it, and test the mc on the freshly split face.
 
When you turn it to low how low are we talking here?


Lopi Rockport
Blaze King Ashford 25

Well, upon loading and once it gets going I close the bypass. Then when it’s in the active zone, to get it to heat up the living room, I let it rip for 15-20 min or so than turn it down to about 3:00... 2:00 on the dial the valve goes “clink” so I back it off.

Now I don’t usually run it on low due to there isn’t much heat on low. So my wood, oak, must be still too wet. Maybe I’ll buy two bundles of kiln dried wood... pack it completely full, once it’s going set it on low with fan on low to measure burn time.


Sent from my iPhone using Tapatalk
 
The blowers cause a false reading on the cat probe. Turn them off for 10 minutes before checking.

You have something else going on too. Having to turn a bk up to medium to get heat, with 20% mc wood?

Either your wood is way wetter or some other problem exists.

Let some wood warm up to room temp, then split it, and test the mc on the freshly split face.

Okay. I’ll bring some in this evening and let it warm up. Split a few pieces and check MC.


Sent from my iPhone using Tapatalk
 
Well, upon loading and once it gets going I close the bypass. Then when it’s in the active zone, to get it to heat up the living room, I let it rip for 15-20 min or so than turn it down to about 3:00... 2:00 on the dial the valve goes “clink” so I back it off.

Now I don’t usually run it on low due to there isn’t much heat on low. So my wood, oak, must be still too wet. Maybe I’ll buy two bundles of kiln dried wood... pack it completely full, once it’s going set it on low with fan on low to measure burn time.


Sent from my iPhone using Tapatalk

That’s good that you don’t go lower than 2. On low at 2 on mine in the room where it is at is also my game room. I eventually have to move cause it gets too warm in there. I think your wood is the issue here.


Lopi Rockport
Blaze King Ashford 25
 
After a few futile searches I figure I'll just ask. How do you tell if a cat is bad? I have a Princess, manufactured in 2006. I bought it used in 2016 and I'm in my 3rd burning season. Usually light it up in Oct and burn constant through March. Burn red and white fir and lodgepole and maybe use 1/2 cord month. When it gets 20 deg and below I usually get a minimum of 12-14 hour burn. Cat seems to light off, glow properly and stays active through the burn. I have done the vinegar clean twice. The cat does have a crack in the center but seems stable and is not crumbling. Just curious as I've put around 11k hours and I'm not sure how much the PO used it (it was like new).

Second question is burn time. I've read that burn times decrease when a cat is failing. Is this because the air has to be increased or does a cat really effect burn times? I'm trying to understand how if a cat is not plugged how a failure can reduce burn times. Sorry if this has been covered before. So far I'm very happy with the stove. Saves me a fortune in propane.

It impacts burn times greatly because it makes a good fraction of your heat at high settings, and it makes the majority of your heat at low settings. If the cat isn't making much heat, the thermostat calls for more intake air, and your wood goes faster.

It sounds like you're running the stove medium-low most of the time, and your burn times meet my expectations for medium low with pine in the gas tank, so your cat is clearly not dead, but it could be doing better.

I'd order a new one now and swap it next time you shut down for flue cleaning. You don't have to, as the old one is still doing some work, but you will get more heat for less wood with a new cat.
 
I’m doing something wrong or my wood is terrible. My cat only stays active if the box is stuffed and blazing. Once it burns down it falls out of active zone quickly.

I’m not sure you’re doing something wrong. A few things to consider:

1. Once active, the cat needs fuel to stay active. Once the wood load has released most of its volatiles, depending on species, and you may just not have enough fuel going thru it to keep it active.

2. You could have a cat thermometer (yes, I know the inserts use a bang/bang on/off needle, not the typical wound bimetallic needle) that is out of whack. Don’t assume everything is as it should be.

3. I report my cat staying active for very long stretches, burning oak, but what that really means is the exhaust coming off the back of the combustor is over 500F. For all we know, the cat may NOT be active as in eating fresh fuel, but the exhaust temp of the primary burn is just hot enough to keep the air flowing thru the combustor that hot. Who knows?

Ah but this happens automatically, the thermostat does this without asking.
Excellent point. I was speaking of stoves in general, as most of my failing cat experience was with Jotuls, and not remembering this is the BK thread.
 
  • Like
Reactions: Highbeam and jetsam
3. I report my cat staying active for very long stretches, burning oak, but what that really means is the exhaust coming off the back of the combustor is over 500F. For all we know, the cat may NOT be active as in eating fresh fuel, but the exhaust temp of the primary burn is just hot enough to keep the air flowing thru the combustor that hot. Who knows?

Guys with a thermocouple in front of and behind their cats know.

You're going to need a drill and some copper tubing... :)
 
Status
Not open for further replies.