BKK blowers- can you burn them out?

[Renovation]

Beetle, are you locking your bypass down. Clockwise. Hearing the second thunk after it stops? I dont think I have ever seen my flue temps above 350F. Not on a medium burn #2 once its settled in. :coolhmm:

Yes, BK's intro video specifically shows how to adjust it for correct engagement, so it seems adjustment and correct engagement are important.

Hey BeetleKill--

Any update on this? I'm curious if you found your cat was engaging fully, and if that lowered your flue temps.

 

[HotCoals]

BTW..I can get the stove top higher with the blowers off.

That makes sense--you're loading/cooling it with the fan, making your heating more convective (hot air) and less radiant (hot stove). Does it make the heat seem softer, less harsh?

I don't mind the fans on low or so..it does seem to soften the heat unless you are standing right in front of it .
Mostly the fan is off,when it gets to colder weather we will see.
I know with the old stove I never ran the fans much...the ceiling fan sometimes.

 

[ecocavalier02]

I'm thinking he might have single wall pipe or that's internal flue temp.

 

[Renovation]

I'm thinking he might have single wall pipe or that's internal flue temp.

If BK had that flue surface temp with double wall pipe, the reason we're not hearing from him is his house burned down.

As I gather, his flue temp was higher than most, and he was reporting poor heating performance, leading someone to suggest he check if his cat was engaging fully.

 

[Beetle-Kill]

Sorry for the delay, home computer went south again. To answer- flue pipe is double wall, probe is 19.5" above stove top, and the CAT is active. VERY active. After a few hours, the flue temp. had dropped to 100 degrees less than stove top. I was checking it about an hour after closing the by-pass. And yes, the by-pass is closed and locked. Little extra tug to cam it in place.I need to do the dollar bill test again, as the closing wedge on the door handle is aluminum, and I've worn a slight groove in it where it closes against the latch. Door closes very easy compared to new. I may have to machine one out of steel it this continues.

 

[fdegree]

I too am only about 2 weeks in with a new BK. This past weekend was the coldest yet...20's at night and maybe as high as 40 during the day...these temps only lasted for 2 days, but more cold weather coming later this week.

My home was built in 2004, so it is fairly well insulated. This is a single story home, and I'm heating all 2300 sq. ft. with this stove.

Anyway, I am burning with white oak, exclusively...fairly high moisture content, averaging around 25% - 28% back in October. I was getting 30 - 36 hours on a full load with the t'stat set around the 1.75 mark most of the time. The only time I had to turn the t'stat setting up was when I was down to just coals...but never had to go past the 2.0 setting. This kept my main living area, consisting of the living room, dining room and kitchen, between 70 and 75...bedrooms usually 3 - 5 degrees cooler, depending upon how long we kept the bedroom doors open.

The stove is located in the living room...we have a ceiling fan in the living room too. The ceiling fan stays on low speed, with the air being blown upwards, 24/7 while the stove is burning. The stove fans are usually off unless the cat temp rises to 1500 degrees or more...then I turn the stove fans on low until the cat temp drops. The only other time I turn on the stove fans is if the house temp drops and I want to heat it back up quickly...which has happened after the stove is down to just coals and I haven't reloaded yet.

Just thought I would share my experience thus far. Things will likely change some once winter really sets in and the wind starts howling across the field behind my house.

Beetle-Kill:
I'm no expert, but I would think the stove fans would be fine. Maybe exercise them once in while, and place a drop of electric motor oil on the shaft once a year.

RenovationGeorge:
I would recommend the stove fans. There may be occasions that you'll wish you had them...I know there have been times that I'm glad I have them, even though I don't use them much. But, if you don't want to go through the initial expense, you could always add them at a later time if you find out they would be helpful.

 

[Lanningjw]

I run the fan all the time with the Princess Insert. the back half of the insert is surrounded with brick and must not run as cool as the princess stove or king model. If I dont turn the t-stat down to low and run the fan on high it will go up to 2000 degrees and shorten the life of the cat....

 

[Renovation]

RenovationGeorge:
I would recommend the stove fans. There may be occasions that you'll wish you had them...I know there have been times that I'm glad I have them, even though I don't use them much. But, if you don't want to go through the initial expense, you could always add them at a later time if you find out they would be helpful.

Hi FDegree,

Thanks for your recommendation.

The reason I'm leaning against BK's fans for now is that the rear shield involved would get in the way of air circulation from my ceiling fan, which I'm expecting to be quieter and more effective. Yessir, if that doesn't work out, I'll add them later.

Thanks again!

 

[Renovation]

Sorry for the delay, home computer went south again. To answer- flue pipe is double wall, probe is 19.5" above stove top, and the CAT is active. VERY active. After a few hours, the flue temp. had dropped to 100 degrees less than stove top. I was checking it about an hour after closing the by-pass. And yes, the by-pass is closed and locked. Little extra tug to cam it in place.I need to do the dollar bill test again, as the closing wedge on the door handle is aluminum, and I've worn a slight groove in it where it closes against the latch. Door closes very easy compared to new. I may have to machine one out of steel it this continues.

Thanks for the update Beetle, and yes, PC dirt naps happen. The problem-solving here is surprisingly interesting, and I like to hear (read) how it turns out. Sounds like a dollar-bill test is in your future--if you ever shut off your stove.

I'm still trying to get a handle on the cat activity/flue temp relationship. In one of BK's brochures they show a graph of cat temp and internal flue temp 48" above the stove top, for a low-and-slow 48 hour burn. In it the cat temp spikes as high as 1350*, but the flue temp stays at about 200* the whole time, regardless of cat temp. Maybe I'll start another thread asking what folk's experiences with those relative temps are. I sincerely don't know how there can be such a huge difference in those two temps, but of course I know nothing about stove engineering.

 

[HotCoals]

Sorry for the delay, home computer went south again. To answer- flue pipe is double wall, probe is 19.5" above stove top, and the CAT is active. VERY active. After a few hours, the flue temp. had dropped to 100 degrees less than stove top. I was checking it about an hour after closing the by-pass. And yes, the by-pass is closed and locked. Little extra tug to cam it in place.I need to do the dollar bill test again, as the closing wedge on the door handle is aluminum, and I've worn a slight groove in it where it closes against the latch. Door closes very easy compared to new. I may have to machine one out of steel it this continues.

Thanks for the update Beetle, and yes, PC dirt naps happen. The problem-solving here is surprisingly interesting, and I like to hear (read) how it turns out. Sounds like a dollar-bill test is in your future--if you ever shut off your stove.

I'm still trying to get a handle on the cat activity/flue temp relationship. In one of BK's brochures they show a graph of cat temp and internal flue temp 48" above the stove top, for a low-and-slow 48 hour burn. In it the cat temp spikes as high as 1350*, but the flue temp stays at about 200* the whole time, regardless of cat temp. Maybe I'll start another thread asking what folk's experiences with those relative temps are. I sincerely don't know how there can be such a huge difference in those two temps, but of course I know nothing about stove engineering.

It is strange.
My flue temps are crazy cold compared to my old non cat bk...even at a 650 stove top temp.
I don't know how the heck it can be.
It even seems that way with the by-pass open...but not so much then.
Having the heat go horizontal to get to the cat must be most of it I guess.
but yet I think after the cat burns off the particulates you would think that would raise flue temps since it's so close to the flue...go figure.

 

[SolarAndWood]

I'm still trying to get a handle on the cat activity/flue temp relationship. In one of BK's brochures they show a graph of cat temp and internal flue temp 48" above the stove top, for a low-and-slow 48 hour burn. In it the cat temp spikes as high as 1350*, but the flue temp stays at about 200* the whole time, regardless of cat temp. Maybe I'll start another thread asking what folk's experiences with those relative temps are. I sincerely don't know how there can be such a huge difference in those two temps, but of course I know nothing about stove engineering.

A lot of heat comes off the top of these stoves. Seems to me the biggest reason to have the blowers is so that you can extract all that heat effectively and efficiently. My new hearth is going to feed the blower assembly with a cold air return from the far end of the house. I will probably just put an inline fan in the duct and get the benefits of moving air right across the top of the stove and pulling cold air from the far end of the house while not having to listen to the blowers. I would consider something like this while you have your house open anyway.

 

[Beetle-Kill]

I think that my seemingly high flue temps are due to the fact I can't run the stove blow #2 on the thermostat, and expect to heat the house. I am running 2.5-3+ most of the time. More air flow through the CAT would increase the flue temps. Once it settles down though, the flue will be less than the stove top by about 100 deg. or so. I am going to mock up a convection deck to see if getting that air flow directed out front will help keep the front room warm. And next summer, baffles on the air-wash, to see if it helps keep the low corners of the glass clean. Gotta love a plate steel stove.

 

[Renovation]

A lot of heat comes off the top of these stoves. Seems to me the biggest reason to have the blowers is so that you can extract all that heat effectively and efficiently. My new hearth is going to feed the blower assembly with a cold air return from the far end of the house. I will probably just put an inline fan in the duct and get the benefits of moving air right across the top of the stove and pulling cold air from the far end of the house while not having to listen to the blowers. I would consider something like this while you have your house open anyway.

Yes, I am indeed considering just these things, good sir. It took me a bit of pondering to understand your idea, but if if I understand correctly, that CAR will no longer be connected to your furnace, but just run between the cold room and your stove? That's so crazy it just might work! If so, are you concerned about upsetting the balance of your HVAC in the cold room? If it's still connected to your furnace, are you worried about, well the same thing? (Always with the questions!)

In my similar contemplations, I'm thinking of moving a HVAC outlet so that it exits in the air space behind the metal shield behind my stove, angled to blow upwards. Then it will aid the natural convection behind the shield, and help move air from behind the stove into the room. You might consider that too--the combination might be a double punch. Thoughts?

Agreed that the blower is a very efficient way to get heat out of a stove. My only real concern (apart from it being too easy) is the noise. Now that I think of it, I suppose I could use a duct with an inline fan instead of the factory blower. Do you know how noisy those duct fans are?

Thanks for your ideas!

 

[Renovation]

I think that my seemingly high flue temps are due to the fact I can't run the stove blow #2 on the thermostat, and expect to heat the house. I am running 2.5-3+ most of the time. More air flow through the CAT would increase the flue temps. Once it settles down though, the flue will be less than the stove top by about 100 deg. or so.

Many thanks for the info. That makes sense to me--BK's 48 hour burn must have been on the lowest thermostat and load (in other words, high room temperature, no fan) possible. So it has lazy air flow giving up heat before it gets to the flue. I'm continually amazed that any burning stove can have a flue temp below 200*.

 

[SolarAndWood]

but if if I understand correctly, that CAR will no longer be connected to your furnace, but just run between the cold room and your stove? That’s so crazy it just might work! wink If so, are you concerned about upsetting the balance of your HVAC in the cold room?

Not at all! I ripped the propane forced air furnace and all the nasty duct work out of the house 4 years ago ;-) A dedicated cold air return can only help. Might even do 4 to the 3 bedrooms and the bath, then tie them together for the haul to the stove. When I get around to central heating, it will be zoned radiant.

Can't take credit for the idea, picked it up here a few months ago.

 

[Renovation]

but if if I understand correctly, that CAR will no longer be connected to your furnace, but just run between the cold room and your stove? That’s so crazy it just might work! wink If so, are you concerned about upsetting the balance of your HVAC in the cold room?

Not at all! I ripped the propane forced air furnace and all the nasty duct work out of the house 4 years ago ;-)

Out, into the snow! Wow, that's commitment--no going back now.

I've gone the other way, and optimized my HVAC for a free-standing wood stove. I put in extra ducts and returns, ran all the ductwork on interior walls, and purchased one of those super-efficient DC fans to circulate the air. I hope it works.

A dedicated cold air return can only help. Might even do 4 to the 3 bedrooms and the bath, then tie them together for the haul to the stove. When I get around to central heating, it will be zoned radiant.

Hot water, heated by wood? Nice.

Can't take credit for the idea, picked it up here a few months ago.

Thanks for passing it on. It's fun finding clever ways to combine and improve technologies, use the new to improve the old, and vice versa. Plenty to still be learned.

 

[Beetle-Kill]

Solar- Damn you, 'cause I like that idea of the cold air return- and it'll probably work for me quite nicely. The picture in my head, of the circulation of hot/cold/hot.... works for me in my situation. And now -thanks to you- I get to do even more work on my ducting. Your in-line fan even sucks, because I designed a system for a buddy using that same principal that works for him, and I still get free beer after two years.Now- I say your ideas "suck", because they work, and even though I haven't implemented them into my house yet, they re-inforce my ideas- which means I HAVE to do more work Hence- you suck. :cheese:

 

[SolarAndWood]

Not at all! I ripped the propane forced air furnace and all the nasty duct work out of the house 4 years ago ;-)

Out, into the snow! Wow, that's commitment--no going back now.

Well not totally. The guts of the original 60s electric system are there, I had to remove the baseboards when I replaced the load bearing walls in prep for the roof trusses. I could probably reinstall them in a weekend if needed. Yes, the boiler will be wood fired and will likely have an electric backup. A lot of other things to do before that though.

 

[SolarAndWood]

Your in-line fan even sucks, because I designed a system for a buddy using that same principal that works for him, and I still get free beer after two years.

How does that work and how effective is it? I am amazed how well just the cheapo fan on the floor in the hall blowing back towards the stove does. If you could feed the blower deck with air from the floor at the far end of the house, it seems like you would end up with excellent consistent overall circulation and maximize the heat exchange on the stove.

 

[Beetle-Kill]

Solar, it works pretty good in his situation. He's got a 2000 sq. ft. modular over an unfinished basement. We plumbed in a rectangular duct from the ceiling in his stove room, to pull the hot air out. Ran it to an in-line fan( i think it was a 6 or 8"), coupled it with rubber isolators to keep the noise and vibration to a min. From there, we plumbed it to a floor register in a back room. The air gets pushed back towards the stove room. Once the house is up to temp., the interior stays very even in temperature.

 

[Renovation]

Solar, it works pretty good in his situation. He's got a 2000 sq. ft. modular over an unfinished basement. We plumbed in a rectangular duct from the ceiling in his stove room, to pull the hot air out. Ran it to an in-line fan( i think it was a 6 or 8"), coupled it with rubber isolators to keep the noise and vibration to a min. From there, we plumbed it to a floor register in a back room. The air gets pushed back towards the stove room. Once the house is up to temp., the interior stays very even in temperature.

Veeeeeeery interesting!

Can you tell me a bit about the fan--kind/source, were the rubber isolators a standard item or something you made, and how noisy was it--quieter than a stove blower?