How to clean glass and can't get low temp on Blaze King

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The drywall is safe up to around 170F. It will feel too hot to hold your hand there at 130F. When in doubt measure the temp with an IR thermometer.
 
with out the cat engaged, your wasting your wood and emitting more pollutants than the stove was designed to emit. Next question is how dry is your wood. Once the wood is chared and in the active zone you should be able to dial the air down and watch the cat temp climb. When throttled down you will get some deposits on the glass. The glass will stay cleaner when you start running the stove hotter
Again, running the stove hotter to clean the glass, makes the house too hot and I have to have the windows open. My wood is thoroughly dried and tested for sure. I burn seasoned pine, fur and spruce.
 
Hmm, well if it’s enough to concern you then it’s worth checking out. I think it’s responsible to take wood burning seriously in your home. I certainly cant leave my hand on the back of the stove without it getting burnt! But I agree if your drywall is getting so hot you can’t touch it then that’s an issue. When i run my stove wide open stuffed full of jack pine (oh no, not jack pine!) i can get my wall behind the stove pretty warm, but never so hot that it cant be touched. Stove or pipe on the other hand, and i’d be branding myself for sure!

Have you used a thermal imaging device to actually determine the temperatures you’re feeling to know for certain that your stove is running too hot?

Please keep us posted on what you discover.
All I have is an infrared temperature sensor to register the wall temp. It just baffles me, that no matter how I place the wood in the firebox, or the quantity used, I still have creosote issues withing 2 or 3 days.
 
Again, running the stove hotter to clean the glass, makes the house too hot and I have to have the windows open. My wood is thoroughly dried and tested for sure. I burn seasoned pine, fur and spruce.
A black stove window is likely to happen when the stove is running exceptionally low and slow. It's still pretty mild right now but temps will be dropping next week. When they are below 5ºC the stove may be able to be run hotter without overheating the house.
 
with out the cat engaged, your wasting your wood and emitting more pollutants than the stove was designed to emit. Next question is how dry is your wood. Once the wood is chared and in the active zone you should be able to dial the air down and watch the cat temp climb. When throttled down you will get some deposits on the glass. The glass will stay cleaner when you start running the stove hotter
The wood is very dry, down to 5%. Pine, spruce, fir is what I have available. Running the stove hotter for say, 2 to 3 hours cooks the house which is 1500 sq.ft. upper level where the stove is.
 
I think the box of a cat stove can look a lot worse than the flue when running low. The cat chews up all that creosote making smoke. Far as I've ever heard it's part of the gig, looking at the fire in a BK isn't where it's at, at least when running low and slow. What's the cap looking like?
By end of the winter the outside cap looks rather sooted and a bit creosoted up. The flue (about 15 ft long) had a mix of sooted ash and a bit creosoted, maybe about a gallon jug full of it after sweeping it clean.
 
It can take a while to get used to a new stove. It will not burn like the previous non-cat stoves. Both Webby3650 and Ashful report the glass staying 'reasonably' clean but they have big barns to heat and run the stove at a higher setting. At a low setting the glass is going to get gunked up. To clean the glass some folks report using a razor blade as a scraper to remove heavy buildup. If the cat temp is dropping it could be that it's stalling and needs more air.
Your reply makes sense to me. I cannot run the unit hot for too long because the 1500 sq. foot room becomes way to warm and I have to have the windows open. I wonder if it would have been better for me to have had the Ashford A20 in stead so I can burn smaller volumes at higher temps to keep the glass cleaner?
 
I used razor blade and oven cleaner (cold). Any chance glass gasket is not doing it's job? Air Leak? My old BK King did the same thing. Would only have clean glass when I ran it full bore. When temps were warm outside I had to dial it down to Medium or low. Lucky for me I had clean out outside I could run brush thru. Black junk would clog up the cap. I would clean it once a month or so. Depending on how much snow and temps. (Chimney) I just learned to live with it. I switched to pellet stove. Cleanup is a breeze. Wet and dry paper towel. 5 seconds like new. Don't miss the royal pain wood was getting to be.

When I ran the stove and got the temps up and closed the bypass to put it in Cat Mode the temp would go even higher (normal). In get good 10-12 hours on full stove (overnight).
I think you are right on point here my friend. I have heard cat stoves burn different to non-cat type; and yes, pellet stoves are way less gunky for sure.
 
A razor blade can remove the heavy stuff. When cool use a small dense plastic scrub brush wet with Rutland glass cleaner. The brush gets it off quick. Wipe residue off with dry paper towel. Can do a VC Encore in about 10 minutes this way. Kevin
I will try these suggestions in detail. I have only been using a paint scraper, plastic scouring pad and wet paper.
 
The biggest factors for clean glass for me are:
  • Reload when it's still nice and hot with lots of coals to get the fuel going quickly, rake the coals to the front and keep you new fuel towards the back.
  • After reload, I run it on high (with the bypass closed) until my flue (insertion) is over 600 for at least 10minutes, then I step it down to my cruise setting in a 2 or 3 steps over the next 10-15 minutes. It might take anywhere from 10-30 minutes to heat up nicely depending on how dry and how much wood I loaded. (this is the biggest factor).
  • Don't stall it, nothing soils the glass more than a stalled out stove smoldering for hours.
  • It won't fully self clean, but raking the coals forwards with a east west log in the back half on high does clean things up quite a bit.
  • I get a bunch of creosote buildup in the stove, but my chimney was pretty good after a season of burning (15' straight up excel).
  • Make sure you wood isn't cut too long, you want laminar fresh air flow on the glass. If you have wood protruding too close to the glass, things get turbulent and the smoke swirls against the glass.
  • I don't worry about it too much, there just isn't enough heat to keep the inner glass and firebox surfaces above the creosote deposit temps at lower burns.
I wonder if Woodstock style double pane glass would keep the inside hot enough to avoid getting dirty?
Really helpful reply. I will try this in detail this winter and report my findings. Thanks so much buddy.
 
Are you loading E/W or N/S? If N/S, how long are the pieces? Near glass? Using smaller size (diameter) to fill stove creates more space for air circulation. But it will shorten burn times due to added surface area.
I have tried every compass direction, different lengths of wood, different volumes of wood, wood near glss and far from it. Humidity of wood down to 5%. Flue height about 17 ft including two 45 degree elbows.
 
Your reply makes sense to me. I cannot run the unit hot for too long because the 1500 sq. foot room becomes way to warm and I have to have the windows open. I wonder if it would have been better for me to have had the Ashford A20 in stead so I can burn smaller volumes at higher temps to keep the glass cleaner?
The A20 would not make a difference. Its bottom level output is about the same. This is basic physics. The room is evidently well-insulated and outside temps are still mild. It sounds like the space could easily be heated in this weather by electric baseboard or a mini-split heat pump, or a pellet stove. The difference is that these heaters turn off when the call for heat is satisfied. The wood stove can not turn off. It will burn as long as there is fuel in the firebox.
 
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I have tried every compass direction, different lengths of wood, different volumes of wood, wood near glss and far from it. Humidity of wood down to 5%. Flue height about 17 ft including two 45 degree elbows.
How is the wood being tested? 5% is extraordinarily hard to achieve. Is the firewood to be tested resplit, then tested on the freshly exposed, interior face of the wood? Ideally this should be with the wood at room temperature.
 
My wood is well seasoned and under very good protected shelter. The split wood is anywhere from 8 to 3 years seasoned. I use a high quality moisture meter and probe from about 2 or 3 inches in from each end of a split piece. I bring the wood into the house and it acclimatizes to the room temp for a few hours or more.
 
That's good for testing if the wood is resplit before testing. The best I can get on my meter is 14%. This is after our drought summer and a bit hotter temps south of BC. I have 4 yr old hardwood in the shed that still tests at 16%. The wood settles into that level due to ambient humidity. Super dry finishing wood and flooring that is kiln dried is lucky to come in at 7-8%.
 
Sometimes super dry wood is as bad a problem as wet wood, for it out gasses so much so quick it overcomes the cats ability to digest it,. Same applies to a secondary burn type stove in which case things go ballistic quickly.
 
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Another data point, for whatever it is worth: I'm currently burning wood originally cut into rounds 7 or 8 years ago and stored under cover since, then split within the last couple of months. Usual PWN mix of species; lots of alder, a fair amount of cedar and hemlock, some maple, some pine. After splitting again and storing indoors for 24 hours, my moisture meter shows between 12% and 13% for most species.

My recently installed BK Princess is currently running on low (thermostat at around 4 o'clock) with roughly 1/2 loads. Similar procedure to Superj's quote: run it on high for 10 minutes or so, then close the bypass (waiting until the cat gauge is at 11 o'clock or higher), wait 5 or so minutes and then reduce the air every 5 to 10 minutes from 6 o'oclock to 5 to 4. Sometimes a small hot reload at 8 to 12 hours; sometimes let it run overnight until cold or coals in the morning. Similar process used for both hot reloads and cold starts. The glass cleans up some during the initial hot run, then blackens again. Never quite reaches entirely clean.

The space is around 1800 ft^2 with 13 foot cathedral ceilings. Outside temps have mostly been in the 50s. The space stays mid-70s all day.

Don't have a flue thermometer (yet), so not sure what the flue temps are. Total stove pipe (double wall) + chimney is around 18 feet.
 
It is not reasonable to expect a BK burning on medium or low to self clean or to stay clean in the firebox which includes the glass. The glass is very cold and will accumulate a “bark” in the lower corners especially. This is normal and is one of the trade offs you make for the ability to burn wood so slowly.

A whole second issue is shoulder season burning in a small home. It’s tough. Get used to big temperature swings. Lots of small fires. Or do something else for heat. Today, for example, we had frost on the roof in the morning but high enough daytime temperatures that baking in the oven will prevent me from burning a fire tonight.
 
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That's good for testing if the wood is resplit before testing. The best I can get on my meter is 14%. This is after our drought summer and a bit hotter temps south of BC. I have 4 yr old hardwood in the shed that still tests at 16%. The wood settles into that level due to ambient humidity. Super dry finishing wood and flooring that is kiln dried is lucky to come in at 7-8%.
BeGreen, Louisville baseball bats are 6%.
 
BeGreen, Louisville baseball bats are 6%.
Relevant? They are vacuum dried, often flare tempered, and then finish sealed.
 
Relevant? They are vacuum dried, often flare tempered, and then finish sealed.
And after all of that...they are still 6%
 
It's highly unlikely that cut, split and stacked firewood (ours is indoors), can get to 5%. Using a Delmhorst J2000, we can specify species and density and still never see such low numbers.