BK or NC-30?

  • 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.
  • Super Cedar firestarters 30% discount Use code Hearth2024 Click here
Status
Not open for further replies.
Less than 1gm/hr in this testing.

Chris's presentation here. Chart that follows shows 85% after 9 years. Not sure, but I would guess this was with ceramic cats based on the date of presentation.
(broken link removed to http://nficertified.org/admin/ExpoFiles/Neufeld%20EvaluatingCatalyticWoodStoves.pdf)
Life of a Combustor
• The Anticipated Operational Life is Up to 10 Years
• Studies were Performed Independently by Omni Environmental Laboratories
• The Omni aging study conducted in December of Catalytic Hearth Coalition All Rights Reserved The Omni aging study conducted in December of 2009 Showed Limited Reduction in Activity After Multiple Seasons of Use
• All Combustors In the Study had a minimum of 3 cords burned each year
 
Late to the party, travelling this week, see i got tagged by bg a few days ago.

Enjoy your new PE Iron, i startwd with a non cat a few years ago. You got plenty of xhimney height to plug and play a cat stove a few years down the road if you want to.

Fairbanks is a partly enclosed airshed like Seattle or LA. When we get an inversion layer, all wmissions arw trapped, cars, wood stoves, outhouses, th power plant that makes our elecrricity, all of it.

For me local stage one is voluntary no ban, stage ii only stoves under 2.5 g/hr can be reloaded, stage iii no solid fuel heating device can be reloaded unless you got a no other adequate source of heat exemption.

All cat stoves will blacken the glass at low output settings. It does burn off quick.

BRB, i have a thing...
 
The local air law is 20 minutes unregulated stack output, and then clean plume to next reload.

I basically cant do it. I can get from cold stove to clean plume in 25 minutes consistently, and i can get from cold start to clean plume in 22 minutes ovcasionally. This is using cord wood at 16%mc with 16 to 20 inches of 2x4 (7% MC) split real small for kindling.

It is a BS reg that shouldnt be on the books at all. I called the sheriffs office in whatever county contains Tacoma, WA last year and they said noone had ever been ticketed for prolonged cold start... nut the truth is they could probably ticket just about everyone for it if they need to come up with some dinero to pay for alderman jones taking his mistress to cabo sam lucas for christmas

Sorry, i know this is a family web site and all and 12 year olds are suppose to be able to read every word i post here without having to say "Father, what does it mean when Poindexter says something chaps his ass?"

Maybe i ought to come back to this later. In the meantime enjoy your noncat. When you get sick and tired of wild temp swings, we'll talk about cat stoves.

For my BK to not freight train on hot reloads i toss wood dried to 16% MC or less onto hot coals, stay in bypass to the first tick mark above the active zone, and find a clean plume as fast as i can slip my boots on and gwt outdoors to check the plume after flipping the lever.
 
@begreen above. Ooooh i am pissed about that 20 minute cold start thing.

Thanks a bunch @iron, Ill probably get the ban hammer for this.
 
No problem. Note though no wild temp swings with our Alderlea either. We had those with the radiant Jotul but the cast iron jacketed T6 evened them out very well. I've never run an NC30 but there are a lot of happy campers here that have so I'll let them comment on swing.
 
well, right now, i seem to be on the fence. nc30 doesn't seem appropriate. i'm tempted to just finish off the alcove for this winter and see what it's like to use the upstairs northstar fireplace and recirc air from the furnace.

having a black box isn't aesthetically pleasing to think about. but, i know, like with splitting wood, the novelty wears off the more you do it. after several years, i'm sure you want the simplest, most efficient thing out there, and that sounds like the BK - as ugly as it might be.
 
The Ashford is a good looking BK stove. It's nicely finished.
[Hearth.com] BK or NC-30?
 
  • Like
Reactions: Highbeam
No problem. Note though no wild temp swings with our Alderlea either. We had those with the radiant Jotul but the cast iron jacketed T6 evened them out very well. I've never run an NC30 but there are a lot of happy campers here that have so I'll let them comment on swing.

Cat folks often talk about huge temperature swings . . . and honestly . . . I have yet to experience that . . . unless I mess up and reload too soon or too often . . . even with my big ol' radiant Jotul. I am sure cat stoves and jacketed cast iron stoves may smooth out the temps even better, but truthfully once you learn how to run a stove you don't have to truly deal with crazy temperatures where you're freezing one hour and a few hours later sweltering. In the dead of Winter generally the room with the stove -- where we spend most of our time -- is right around the mid-70s . . . dipping down into the low 70s occasionally and going into the high 70s occasionally . . . but rarely out of that "zone" once we're burning 24/7.
 
As BG and Firefighter stated, it is easily doable to run a tube stove without temp swings. I did it, unless a couple degrees either way is a temp swing to you in which case I guess I failed miserably.

But there is a difference! With a steel tube stove it took constant monitoring of the temperature in the home and planning accordingly. This can amount to a good deal of planning ahead during the course of a burning season, or even a day, with a stove that requires reloading sometimes up to 4 times a day in unseasonably cold weather.

I have found it much easier to regulate temps in my home with a cat stove. Once I familiarized myself with the thermostat I began to rely more heavily on the outside temps and 24 hour forecast to dictate how I run the stove. I find this a much easier, set it and forget it, way to run the stove.

With the BK's ability to run for 10 hours~ at 700* or 24 to 30 hours at 300* and any temp you want in between, it's just much easier to maintain steady temps in your home.

(I'm not sure I'm correct about 10 hours at 700*. I've never really needed that much heat so I have no first hand experience with it. I'm sure Poindexter can give first hand experience though.)

Where I live, the weather can be a real roller coaster in the winter so in areas where outside temps are relatively stable it would be even easier to regulate inside temp with any type of stove.
 
Agreed, the temp swing with the Castine was not huge, but there is a notable difference. As the fire died down in the Castine the room cooled down. The mass of cast iron jacket on the T6 acts like a buffering heat sink. The lack of intense side and rear radiance is quite noticeable and so is the continual warmth after the fire died down. We made the stove swap in March so our first experience was during late winter with temps in the 30s. The difference was apparent right away. The trade off being that it is slower to warm a cold house up from a cold start, but in that case I would turn on the blower.
 
dang, a new cat every 3 years? i guess you burn more than we ever would, but still, that's a semi-pricey maintenance cost.

In my case, I burn for nine months of the year on low. The cats are rated by the manufacturer for 10,000 hours of burning and NOT # of cords. A little math tells us that 9 months is steady 6500 hours which we can round down to 5000 so 2 years for me. It is not out of line to expect 3 years for me but many places have a shorter season.

Most woodburners don't heat full time with wood.
 
so at 80% activity, what is the emission rate? if the stove is smoking all the time on reloads, doesn't that kind of defeat the purpose of a clean burning EPA stove?

All stoves smoke all the time on reloads. The EPA ratings are time averaged to account for the variable nature of solid fuel combustion.

You make a good point though that if your cat is 80% effective then your emissions have increased over the initial output. THAT is why cat stoves are required to be cleaner burning than non-cats. The allowable emissions rate from a cat stove is like half of what the non-cat guys are required to accomplish to account for the degradation of the cat over its lifecycle.

IIRC, according to BKVP lifespan of a well-treated cat is 6-10yrs. At 6 yrs I would hope to still have 80% activity.

Note the fine print.... a well treated cat is one that isn't used. A cat in a stove that is not used has an infinite lifespan. Most sources say the cat has a "life" of 10,000 hours or 6 years assuming an arbitrary burning amount per year.

So how long is your burn season? How many hours per day do you expect to burn? We can calculate the expected life of your cat which is not a big deal to replace. Way easier than the door gasket which you will need to replace as well.

The other thing is that a new cat is super awesome. It is extra reactive. So much so that you may be willing to prematurely replace the cat just to keep tip top performance.
 
Cat folks often talk about huge temperature swings . . . and honestly . . . I have yet to experience that . . . unless I mess up and reload too soon or too often . . . even with my big ol' radiant Jotul. I am sure cat stoves and jacketed cast iron stoves may smooth out the temps even better, but truthfully once you learn how to run a stove you don't have to truly deal with crazy temperatures where you're freezing one hour and a few hours later sweltering. In the dead of Winter generally the room with the stove -- where we spend most of our time -- is right around the mid-70s . . . dipping down into the low 70s occasionally and going into the high 70s occasionally . . . but rarely out of that "zone" once we're burning 24/7.

There are stone non-cats that like cast iron non-cats seem to really smooth out the temperature swings. I never had a problem with the swings on my non-cats including the NC30. What I do appreciate about the BK is that the burn cycle is 30 hours and controlled by a thermostat so no need to futz with the air control for 30 hours of steady output. Also important is that the cat can burn much cooler than a non-cat so the stove has a wider range of available outputs. This is hugely important in a location where the temperature is not always the same outside. High output when it's cold and low output when it's warm.

Get good at running a non-cat and you can get great results.
 
  • Like
Reactions: Ashful
What is the difference between closing down the air 5-10 minutes after reloading and closing a bypass? It's trivial. Most non-cat stoves I have owned can run from about 400F stove top to 700F stove top depending on how it's loaded, air setting, timing and the fuel choice. That gives one a fair amount of control. The thermostatic control on the original VC stoves also did this automatically, in a non-cat stove. The main advantage of the cat is longer burn time which is great. However that doesn't mean a home can't be heated comfortably with a non-cat stove. It's done all the time.
 
Last edited:
Wow now I am considering the BK Ashford again. I like the look of the BK over the PE Newcastle. Just really do not want to have a smoking stove in the many shoulder days of Puget sound region.
 
Those of you trying to get around the burn-ban on a cold start - could you use an Eco-brick or construction scraps for 20 minutes to get the catalyst up to clean-burning temperature, then load with firewood? They should have very low moisture content and therefore low emissions for quick, clean heat.
 
Those of you trying to get around the burn-ban on a cold start - could you use an Eco-brick or construction scraps for 20 minutes to get the catalyst up to clean-burning temperature, then load with firewood? They should have very low moisture content and therefore low emissions for quick, clean heat.
Poindexter posted his valiant attempts to minimize smoking during startup.
https://www.hearth.com/talk/threads/regulated-burners-cold-start-tips.140279/
Here is another thread on stove warm up that may be interesting.
https://www.hearth.com/talk/threads/how-quickly-does-the-stove-warm-up.148717/
 
Last edited:
in a few weeks, i will be embarking on a complete basement remodel (seismic retrofit, changing layout of walls, insulating the concrete floor and walls of the foundation, etc). we have a jog in the foundation wall that used to house a ZC fireplace that i ripped out during this project (https://www.hearth.com/talk/threads...t-n-glo-northstar-fireplace-with-pics.149631/ - look for the 3rd picture to see the basement area).

originally, we had planned to close off this old fireplace area and frame over it. now, i'm getting the itch to put in a stove there.

i've come to the conclusion that only a BK or an NC-30 makes sense (i either want a cat with incredible burn times, or a tube stove that people love and is cheap).

here are the stats:
basement SF: ~700 in 3 or 4 rooms
chimney run: ~25ft
upstairs will be easily heated by the northstar
floors to be insulated with 1" foam, then subfloor, then carpet
concrete walls to be insulated with sprayed on closed-cell foam to 2" (should be R15 and air sealed)
cripple walls insulated to R13
no concrete will be exposed in the final basement - only drywall and carpet
HVAC is through a heat pump + electric furnace
mild maritime environment

i read through this thread (https://www.hearth.com/talk/threads/blaze-king-king-on-6-chimney.56497/page-2) regarding the use of 6" chimney. if that size actually works, is this an acceptable product (http://www.homedepot.com/p/DuraVent...-Wall-Chimney-Stove-Pipe-6DP-36SS/100144227)?

unfortunately, with last year being our first year burning wood (part time), we didn't experiment a whole lot with heating the whole house options. we did turn on the re-circ fans on the HVAC system once or twice and it seemed to cycle enough warm air down to the basement to make it tolerable (and that's in its currently insulated state, which is poor). but, i'm not sure how it would do in colder spells. also, i like the idea of not using electricity to heat, although i realize the breakeven cost is probably favored towards the recirc air vs stove.

anyway, i just wanted to get your opinions on which stove. we are expecting our first child in a few months, so keeping the house warm all day will be more important than it is for just the two of us. hence, the idea of a BK and 24hr burns sounds nice. plus, if we don't need to heat the upstairs, it seems like it would be a good fit. OTOH, using the nc-30 could be problematic due to spikes in temperature (highs, then lows) and it could possibly cook us out of the room (which is where i expect the future kids to hang out most).

thanks for reading the long-winded brain dump.
You will need a forest literally to provide you with enough wood if you choose the NC.Everyone I know three folks say they eat would in astronomical quantities.Especially with a 25 foot chimney. A no brainer for me a BK.
 
IIRC you have both a tall and a short chimney setup. Do you see differences in behavior or smoke with one setup vs the other?
I can't say I really paid that much attention to this, as it wasn't a problem, so can't really answer as to the exact difference in times between the stoves. What I can say is that I can run the stove on the tall chimney much lower and slower in warm weather, versus the stove on the short chimney.


Sent from my iPhone using Tapatalk
 
You will need a forest literally to provide you with enough wood if you choose the NC.Everyone I know three folks say they eat would in astronomical quantities.Especially with a 25 foot chimney. A no brainer for me a BK.
Winters are milder in western WA state than Ohio. We heat our leaky 89 yr old farmhouse on about 2-2.5 cords a year with a non-cat, 20ft straight up chimney. Above 50F we let the heat pump do the job, it's cleaner, cheaper and easier.
 
FYI: house is 1979 construction, 2x4 walls with R11. just reinsulated the attic up to about R60 including air sealing. basement concrete walls will be insulated to ~R15 and floor to R6 + carpet.

i don't think it's a drafty house and the upstairs northstar was easily able to overheat the upstairs last winter on marginal wood with only 2-3 splits in at a time. the basement is ~1/2 the size of the upstairs.
 
When you guys talk about the fireplace smoking are you saying smoke is going into the house or smoke is going up the chimney. Confused about this.
 
When you guys talk about the fireplace smoking are you saying smoke is going into the house or smoke is going up the chimney. Confused about this.

Chimney smoke during startup and reload. Just like all stoves except for a longer time. Don't get the wrong idea, these things are clean burning. Just know that they will smoke during those two times.
 
Winters are milder in western WA state than Ohio. We heat our leaky 89 yr old farmhouse on about 2-2.5 cords a year with a non-cat, 20ft straight up chimney. Above 50F we let the heat pump do the job, it's cleaner, cheaper and easier.

Boo. You don't heat on 2-2.5 cords per year. You are a part time burner and use your furnace for a large part of the season.
 
  • Like
Reactions: Ashful
Those of you trying to get around the burn-ban on a cold start - could you use an Eco-brick or construction scraps for 20 minutes to get the catalyst up to clean-burning temperature, then load with firewood? They should have very low moisture content and therefore low emissions for quick, clean heat.

I tried this. The bricks smoke more than cordwood. It's not moisture causing the smoke, it's unburnt fuel.
 
Status
Not open for further replies.