Kuuma VF100 arrived

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I have my cold furnace light up down to a science. I can go from a cold furnace to putting a load in about 15-20 minutes. I take one normal sized dry split of pine and split it into small splits, Then I take those and break them in half so I have a good handful of 8-10" long or so dry kindling. I place those on some crumpled up paper. I then open my ash pan door and also tie my BD flap closed (using some thin wire) to give maximum draft and to limit the amount of fresh (cold) air being introduced into the chimney. I then light the paper and wait. I leave the ash pan door open and BD flap tied shut the whole time in order to get the furnace and flue up to temp ASAP. I like to see 500° - 600° flue temps right at the collar of the furnace. I do this as I believe getting the flue pipe and chimney up to temp ASAP helps with any possible creosote buildup which may develop in the stovepipe BD area from doing multiple cold starts over time. The sooner and hotter you can get the stovepipe the better. The hotter you can get the firebox also makes for more efficiency once you load it. Once I get the temps up and all the kindling has turned to coals I then load it. I keep the ash pan door open and BD tied shut for maybe 5 minutes after loading to ensure a good fire has taken hold. I then close the ashpan door and untie the BD to allow for normal operation. This method seems to work great for me. It gets the firebox and chimney up to temp as quickly as possible.
 
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When I start from cold, not warm, but basement temp cold. I also will lite a small fire 1st, then come back 20 min latter to load. I only do this because I don't think its good to take cold steel to blazing hot real quick. If the furnace is out with no coals but the firebrick is warmer than my hand, I will load it up to whats needed for outside temp. Then lite with a torch from the ash pan (10 sec) then when the light turns on close the door and go.
 
When I start from cold, not warm, but basement temp cold. I also will lite a small fire 1st, then come back 20 min latter to load. I only do this because I don't think its good to take cold steel to blazing hot real quick. If the furnace is out with no coals but the firebrick is warmer than my hand, I will load it up to whats needed for outside temp. Then lite with a torch from the ash pan (10 sec) then when the light turns on close the door and go.

I do the same thing for the same reason. I build a small fire to get a small coal bed, wait 20-30 minutes them load.
 
When I start from cold, not warm, but basement temp cold. I also will lite a small fire 1st, then come back 20 min latter to load. I only do this because I don't think its good to take cold steel to blazing hot real quick. If the furnace is out with no coals but the firebrick is warmer than my hand, I will load it up to whats needed for outside temp. Then lite with a torch from the ash pan (10 sec) then when the light turns on close the door and go.

That's how I did things last year, except if I didn't have any coals with a warmish furnace I still started it over again with paper/kindling.
 
Sounds like low draft.
Getting a cheap manometer like the Dwyer Mark II model 25 is a really good way to get (and keep) a handle on your draft situation.
What is your chimney like? I'm guessin that's it in the background of your first pic? Overall height, internal size, masonry or SS lined, internal or external to the house? (if it is not the one in the pic)
It may be a lot better after the weather gets colder too. Some chimneys struggle much over 40* weather

How do you guys use you manometer to check the draft? I do have a Dwyer mark II. It came with a rubber tube and I added a small copper tube, from a refrigerator ice maker kit, to the end of it so I could insert it into the chimney. On my old stove pipe I drilled a hole below the baro to insert the copper tube to get a reading. Is that the best way or can you just stick it into the baro opening? I just installed the stove pipe on my new kuuma and would like to know before I start drilling holes in the new stove pipe. Thanks!
 
I drilled a hole in the stovepipe so I can leave it connected all the time. You want the manometer between the BD and outlet collar of the furnace.
 
If you use your manometer to adjust the draft on the baro damper, why would you need it attached all the time? I can see drilling a hole if you were going to do other measurements.
 
Same reason I have a hole drilled in my stove pipe right at the collar for my Bacharach Tempoint thermometer and also have HVAC thermometers placed in the plenum, supply duct and also in the cold air return. I like to monitor things like that.
 
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But isn't the whole idea of the baro damper to keep draft below a certain level, based on its adjustment? The other stuff you mentioned are things that change-I can see that. Of course, it'd be cool to have it all on a data logger, but that's the subject for another thread.
 
For me it's just confirmation the BD is adjusted correctly and continues to stay adjusted correctly.
 
How do you guys use you manometer to check the draft? I do have a Dwyer mark II. It came with a rubber tube and I added a small copper tube, from a refrigerator ice maker kit, to the end of it so I could insert it into the chimney. On my old stove pipe I drilled a hole below the baro to insert the copper tube to get a reading
More or less what I do.
If you use your manometer to adjust the draft on the baro damper, why would you need it attached all the time?
For me it's just confirmation the BD is adjusted correctly and continues to stay adjusted correctly.
BINGO! I have had baros "hang up" not work correctly...permanent mano monitoring points things like this pretty quick
 
But isn't the whole idea of the baro damper to keep draft below a certain level, based on its adjustment? The other stuff you mentioned are things that change-I can see that. Of course, it'd be cool to have it all on a data logger, but that's the subject for another thread.

You've got a point. Mine has been permanently hooked up & mounted for 3 years now, but once it's set, that's really all you need. Unless maybe you can't easily see your baro & want an easy check on whether it hangs up or not. But with me it's either leave it there or find shelf space for it somewhere, so...
 
I got an inexpensive digital one. Used a couple of times, and yes, it's on the shelf.
 
Good to hear that I'm using my manometer simular to you guys. For those that keep theirs permenatley hooked up, do you need to detach it to zero it out once in a while? I have mine hanging level on a wall with in reach of the furnace and from time to time I need to adjust it to zero before I use it. Just curious.
 
For those that keep theirs permenatley hooked up, do you need to detach it to zero it out once in a while? I have mine hanging level on a wall with in reach of the furnace and from time to time I need to adjust it to zero before I use it. Just curious.
I notice that if you zero it when everything is cold (normal basement temp) it will be different than if you zero after running the furnace 24/7. I suppose the gauge oil expands a bit
 
FYI - for those with a generator backup: according to the manufacturer, the Kuuma Vapor Fire 100 uses 7 amps on high, and 3 amps on low.
 
FYI - for those with a generator backup: according to the manufacturer, the Kuuma Vapor Fire 100 uses 7 amps on high, and 3 amps on low.

of 240 or 120?
 
Amps will fluctuate with each install. The more air moved the more amps.
 
Do any of you experience a lot of fan starts-and-stops when the furnace is getting warmed up?

The blower will go on-of-on off at random intervals. Some "on" intervals as short as 10 seconds. Kuuma says it's because the fan airflow, once it kicks on, proceeds to cool the sensor in the plenum down to just below the "on" threshhold (105F), causing it to go off... and repeat... until the furnace room warms up and it can stay above the threshhold.

That makes sense to me in theory, but it's pretty annoying. Sometimes it'll happen for 30 minutes straight.
 
Do any of you experience a lot of fan starts-and-stops when the furnace is getting warmed up?

The blower will go on-of-on off at random intervals. Some "on" intervals as short as 10 seconds. Kuuma says it's because the fan airflow, once it kicks on, proceeds to cool the sensor in the plenum down to just below the "on" threshhold (105F), causing it to go off... and repeat... until the furnace room warms up and it can stay above the threshhold.

That makes sense to me in theory, but it's pretty annoying. Sometimes it'll happen for 30 minutes straight.

I've noticed the fan kicking on and off at start and wasn't sure what it was, but that makes sense. Unless I'm sitting in the living room in silence it wouldn't bother me. I assume once winter kicks in and the furnace is full non-stop, that the furnace room will stay warm and the plenum won't need much time to warm up and stay at temp. Overall, it's not something that bothers me. Easy pay off for me. Zero propane used so far.
 
Cold startups are very inefficient, as a lot of the BTU's are being used to bring the metal firebox and all it's surroundings up to temp. Once everything is up to temp then things start working like they should and the blower will start to run continuously throughout the burn.
 
I do not and never had that issue. Once my fan turns on iy stays on. To me this sounds more like wet wood, which would make perfect sense.
 
My fan goes in and off too. I've contacted Daryl and he gave me a few pointers. I am burning good wood. Even when the furnace is in pilot mode it still does it. So I finally set the low limit to 100 and it's been better but time will tell. Other than that I love this furnace so far!!!!
 
I do not and never had that issue. Once my fan turns on iy stays on. To me this sounds more like wet wood, which would make perfect sense.
My fan goes in and off too. I've contacted Daryl and he gave me a few pointers. I am burning good wood. Even when the furnace is in pilot mode it still does it. So I finally set the low limit to 100 and it's been better but time will tell. Other than that I love this furnace so far!!!!
Static pressure issue?
 
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