Uh oh...what's this?!

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Yeah we have -40 wind chills coming here. I turned on the LP furnace, for I don't feel like pushing the woodfurnace hard. I may not need it, however I wanted to make sure the LP furnace is okay. Gonna be a test for sure!


I fully expect the LP to kick in a morning or two at some point. It's going to take a ton of BTU's to heat this place in -30° temps for that long of a duration. It's times like this where I'm glad I have things setup the way I do. Peace of mind knowing the LP can kick in and out as it needs to while the Kuuma is doing it's thing.

The LP furnace should also be glad (or is it us....LOL) to have the Kuuma, as I'm pretty sure our 75K BTU LP furnace alone would struggle to heat this place in -30° temps. In fact, they have been saying, in WI, heating systems are designed for -10° to -15°. If you have a programmable thermostat which lets temps fall when not at home they recommend you cancel it and keep house temp up throughout the day until the cold snap ends. Letting the house temp fall may result in the furnace not being able to bring it back up again. I also just got a reminder of this from my HVAC buddy, who normally keeps his set at 60° at night.
 
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I also just got a reminder of this from my HVAC buddy, who normally keeps his set at 60° at night.
Didja tell him yours kicks on at 70*?! ;lol
 
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Like with most HVAC guys, he is not too keen on wood heat. I don't know if he sees it as threat or what. ;lol
That, and wood furnace setup flies in the face of some (most) of their training and some of their logic! ;lol
 
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Gonna run the Kuuma on high, try for 8 hr loads...but if it isn't going well I will not push the issue, just back off and fire the Drolet 1400i up too...rather run the both on "cruise control" than run either one super hard.​

Drive it like you stole it. :) What I tell my dad when he is babying every new car he buys.

Back on topic, I can run my geo and wood furnace at the same time too but I'm going to see if the Caddy can handle the load all by itself. It is suppose to be a balmy -7F tonight and tomorrow night without the windchill. That is nothing compared to the temps @JRHAWK9 and @Case1030 are going to get. Unfortunately the ash I've been burning this year isn't the best. I've cherry picked the good pieces and kept them for the next couple days.​
 
Drive it like you stole it. :) What I tell my dad when he is babying every new car he buys.

Back on topic, I can run my geo and wood furnace at the same time too but I'm going to see if the Caddy can handle the load all by itself. It is suppose to be a balmy -7F tonight and tomorrow night without the windchill. That is nothing compared to the temps @JRHAWK9 and @Case1030 are going to get. Unfortunately the ash I've been burning this year isn't the best. I've cherry picked the good pieces and kept them for the next couple days.​

I agree.....let 'er rip! or as they say today....just SEND IT! ;lol

It was 0° by us at bedtime, -7° when I got up and now it's -4°. House is 76° though!

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It's been a good week for the other half to be gone, as I have to go home at lunch and let the dogs out, so I've also been breaking up my larger morning load into two smaller loads. One in the morning before work and one when I go home for lunch. I also think the smaller loads actually tend to heat better. Thinking I will be doing that tonight. Loading two half loads tonight instead of one large one. Set the alarm to get my butt up to reload.
 
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Remember, however bad you think it is, it could always be worse! !!!




 
meanwhile, I'm charging my "storage", with some help from the sun. ;lol Kuuma has been on high since this morning.


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At lunch I also got gas in my car before the cold hits. Man, it's only -2°, but with the sustained 20mph and 30mph gusts it was down right nasty standing outside waiting for the tank to fill. Exposed skin started to get painful in short order, when subjected to the wind.

Oh, and then on the way back to work I saw some guy riding his BICYCLE on the sidewalk. At least he was riding with the wind.
 
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Stuffed the furnace ( you are welcome @JRHAWK9 ) about three quarters full last night and woke up around 4AM to the house at 70. It was 70 when I went to bed, so I can't complain there. Put four pretty big splits in and when I got up around 7:30 ( had to stay home with the kid today ) the house was 68 and it was 2F out. Burned charcoal for few hours and then loaded it back up around 10 or 11. Outside temps dropped to about -5F and it has climbed back to 0F. I've been loading the furnace about every 6 - 8 hours. House has maintained about 70 or so. We generally don't keep it much above 70. I can't sleep in a warm house.

During these cold temperatures I do miss throwing some oak, locust or cherry into the mix. I've exclusively been burning ash from EAB infected trees that have blown over. Should have some better woods to burn next year. I learned my lesson.

thermostat.jpg
 
I cheated, I built up the house temp to 77°/78° yesterday with the Kuuma, knowing I was going to be losing more BTU's than I could produce, on average, over the burn cycle at the temps we were going to be seeing. Outside temps fell from -2° at 2:30pm to -20° at midnight to -28° at 7am when I got up. I did smaller lighter loads, so I went to bed at midnight, up at 4am to load and then up again at 7am to load and go to work. I'm able to burn more wood with multiple lighter loads than one big one. In these temps, in this sieve of a house, it's all about how fast I can burn the wood, as more wood burned equals more BTU's to the house. May not be burning as efficiently, but the end result is more heat to the house. I burned 210 lbs yesterday. When I went to bed at 12am, it was 75° in the house and -20° outside. When I got up at 4am it was 73° and was 71° in the house at 7am (-28° outside). It's still 71° right now while it warmed up to -12° outside. If I wanted to stay up all night I am confident I could have kept the house temp up higher throughout the night by keeping the Kuuma burning hotter towards the end of the burns by keeping the coals raked forward. This is what I was doing before I went to bed and the house was staying pretty good.

May get close to -40° by us tonight (real temp, not wind chill). Forecast says -35°, but we are always a bit cooler being in a lower lying area.

Really wish this house was sealed/insulated better. Part of it is just the style of the house, with no attic and only ~18" of airspace separating the inside ceiling from the cold outside. The majority of it though is just wasn't built/insulated well and/or with efficiency in mind. :( No excuse in having the amount of heat leaving the roof peak line as what we have. Heck, even the neighbor mentioned something about it to me a couple years ago when helping him with firewood. Mentioned how he notices snow does not stay on the roof for very long and how we must be losing a lot of heat up there. My response was, yeah, I know, thanks for reminding me. ;lol

Every year when we get a cold snap I get a bug up my a$$ to either look into fixing the numerous insulation/sealing issues we have or look into replacing our fireplace with an HE one. Unfortunately, both options are pricey. Then I look at how much the LP furnace actually runs during winter and realize I'd never see the return on investment. Last year it costed us $5 in LP for it to run when we needed it to. It ran a total of 4 hours. Even if some improvement was as cheap as $1,000, it would take us 200 years before we saw the return. ;lol

Sorry for rambling, just "typing" out loud. ;lol
 
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I cheated and turned on my LP for about 5 minutes. Took the house up 2 degrees. Its -5 here now and it's been 70-71 in the house all day, but with the wind feels a little chilly. My lp furnace is oversized now that we have tightened up the house, so by the time the furnace blower kicks off, the house is at least a degree above its set point. I'm not going to worry about kicking the LP on here and there.
 
I'm not going to worry about kicking the LP on here and there.

I go into every winter saying the same thing. Then months later I see a cold forecast and I immediately take it as a challenge.......and then that becomes my mindset. ;lol
 
Well, the worst of this cold spell has passed now...a balmy 8* here for the predicted high today...wind chills are a least 30* higher than yesterday. Never did have to crank the fireplace stove up then...never even had to run the Kuuma on high, medium was the highest setting I used. House was 72* most of the time...had a peak of 73 a time or two...hit 71 a few times...a low of 70 once for a few minutes right after a reload.
I calculate ~150 lbs of wood burnt yesterday.
There is no way the old Tundra would have kept up with this weather...especially considering the added space that we are heating now.
 
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Well, the worst of this cold spell has passed now...a balmy 8* here for the predicted high today...wind chills are a least 30* higher than yesterday. Never did have to crank the fireplace stove up then...never even had to run the Kuuma on high, medium was the highest setting I used. House was 72* most of the time...had a peak of 73 a time or two...hit 71 a few times...a low of 70 once for a few minutes right after a reload.
I calculate ~150 lbs of wood burnt yesterday.
There is now way the old Tundra would have kept up with this weather...especially considering the added space that we are heating now.

It's nice to have a real back to back comparison of heat output. If anything to help others decide on what to purchase. I don't know what the original Tundra you had was rated for, but the Tundra II is actually rated for a higher heat output than the VF100 is. I still think the Kuuma is a bit underrated. Maybe it has to do with the more "peaky" heat output of the Tundra vs the more even heat output throughout the burn of the Kuuma which makes it heat better overall.

Similar to hp in cars. One car may have higher peak HP while another has less peak HP but make more HP throughout the rpm range....a flatter HP curve and more area under the curve. Unless the driver can keep the first one right in it's peak HP rpm range at all times, the one with the flatter HP curve throughout the rpm range will be faster.
 
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Maybe it has to do with the more "peaky" heat output of the Tundra vs the more even heat output throughout the burn of the Kuuma which makes it heat better overall.
I'd agree with that statement one-hundred percent. After I reloaded I noticed the house would get to 71 or so and then throughout the burn it would drop down to 70 or so. When I was burning coals the house would get down to 69 or stay at 70. I'm heating close to 3k square feet ( basement included ) so I'm probably on the high end of what the Caddy was designed to heat.

Does the Kuuma have the coaling "problem" like the Caddy and Tundra's have ? Or maybe ash just creates a lot of coals.
 
Does the Kuuma have the coaling "problem" like the Caddy and Tundra's have ? Or maybe ash just creates a lot of coals.
It would if you were really pushing it hard...like trying to maintain a certain temp in a house that is just too big (or too leaky) for a VF100 to handle. But if you are even somewhat reasonable with your expectations, then no.
I would say @JRHAWK9 is getting 100% out of the SpaceHawk 100 © ;) and I don't think coaling has been unmanageable...
 
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Well, the worst of this cold spell has passed now...a balmy 8* here for the predicted high today...wind chills are a least 30* higher than yesterday. Never did have to crank the fireplace stove up then...never even had to run the Kuuma on high, medium was the highest setting I used. House was 72* most of the time...had a peak of 73 a time or two...hit 71 a few times...a low of 70 once for a few minutes right after a reload.
I calculate ~150 lbs of wood burnt yesterday.
There is no way the old Tundra would have kept up with this weather...especially considering the added space that we are heating now.

How do you think your old vf 200 would have made out?

By what I'm hearing the vf200 is more comparable to the tundra, and the vf100 is closer to the Heatpro.
 
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I would have needed the fireplace stove to help out if I still had the 200, for sure.
Comparing the Tundra to the VF200 for heat output is probably fair.
 
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I'd agree with that statement one-hundred percent. After I reloaded I noticed the house would get to 71 or so and then throughout the burn it would drop down to 70 or so. When I was burning coals the house would get down to 69 or stay at 70. I'm heating close to 3k square feet ( basement included ) so I'm probably on the high end of what the Caddy was designed to heat.

Does the Kuuma have the coaling "problem" like the Caddy and Tundra's have ? Or maybe ash just creates a lot of coals.

Gotta get your hands on some pine. Rake coals forward and toss a few splits on top wide open... good heat output and melts the coals to powder.


I found the same thing with ash (although I was burning borderline seasoned ash.)
 
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I would have needed the fireplace stove to help out if I still had the 200, for sure.
Comparing the Tundra to the VF200 for heat output is probably fair.

I looked for quite a while (maybe not hard enough), can't seem to find firebox size of the vf 100/200?
 
Does the Kuuma have the coaling "problem" like the Caddy and Tundra's have ? Or maybe ash just creates a lot of coals.


It would if you were really pushing it hard...like trying to maintain a certain temp in a house that is just too big (or too leaky) for a VF100 to handle. But if you are even somewhat reasonable with your expectations, then no.
I would say @JRHAWK9 is getting 100% out of the SpaceHawk 100 © ;) and I don't think coaling has been unmanageable...

Like bren said, it's not an issue at all when not in the mode of trying to burn wood fast. Then it's just a minor nuisance. I don't ever load on a crazy amount of coals though, as this will only push the issue down the road and make it even a bigger issue then.

Type of wood also makes a big difference. I'd think burning pine during the real cold nights would work out great for needing to load aggressively. It doesn't leave much for coals and pretty much turns to powder. Just need to re-load more, as I could probably only fit 30-40lbs of pine in my firebox. I heard Elm is similar.

I looked for quite a while (maybe not hard enough), can't seem to find firebox size of the vf 100/200?

4.1CF for the VF100
 
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