Everything Drolet Tundra - Heatmax...
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JRHAWK9
Minister of Fire
heck yeah I would do it again! It works great for me. Yes, I basically boxed out my cold air intake at the blower box and ran it straight up in the air and ended it near the ceiling of the basement. I'm basically pulling in warm air off the ceiling and mixing it with even warmer air off the face of the furnace. I connected the "warm air manifold" from the face of the furnace into the boxed out part of the blower box. Now, keep in mind the Kuuma has one area right on the outside of where a lot of the gassification is taking place right above the door where it's warmer than the rest of the face. This is why I have mine directed right at that area. Your Tundra will be different, but I'd try to find the "hot spot" on your Tundra and take the air off that area.
I attached a photo from a month ago or so showing some temps. I have an indoor/outdoor thermometer and have put the outdoor sensor INSIDE the blower box of the Kuuma so I can monitor return air temps. Yes it's securely fastened so it won't get eaten and spit upstairs by the blower....lol Top is return air temp and bottom is basement temp. My return temp is always more than the temp of the house. It's usually right around 10°-13° more in the middle of the burn, but does get as high as 15°+ more. As you can see, it reached a max of 89° in this particular 24 hour window. Highest I've seen it in the middle of a burn is 90°. The low of 64° is from back when I was just doing a fire a day so the basement cooled down to 64° that day.
Before I did this I was sucking in cold basement air. The highest my cold air temp got before I did all this was like 68°, even when the house/basement was mid 70's. So I went from 65-68 return air to 85+ return air. Even at the end of the burn cycle I'm still seeing high 70's/low 80's for return air temp. Made a big difference in my supply air temps. It also benefits my water coil not having such cold air blowing on it all the time. It also keeps my blower running pretty much non-stop, even between loads.
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Still best would be to run actual returns to the space your heating then maybe steal from the front. A complete install always works best. But if that is not possible jrhawk9's way would be 2nd.
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garmford
Member
I'm glad I did it. My results aren't as significant as jr's but its still good. I'm guessing that I've got less than $30 invested so if it didn't work it's not a huge loss.
JRHAWK9
Minister of Fire
Unless you want the ability to run both furnaces at the same time in extreme weather when ones home has a very high heat load.
I once upon a time built a re burning barrel stove. I made intake tubes from galvanized steel tubes. worked well.
I am finding the newer model Tundra I to run much cooler. Its kinda tough to get it to stay hot it seems. I mean I can really crank it up with some hot burning woods and the fan cools it way too long after the surge portion of the burn is over. I have this idea of possible installing a small air injection device controlled by a 2nd temp controller. To burn a hotter fire thru the last several hours of a burn when we are burning off coals. The time it takes to burn off coals properly before reloading I am finding house temps can drop too far during colder temps. I realize this will shorten the burn times causing more frequent loading but I don't need 14 hr burns with the last 4 hrs being basically no heat. Id rather have hot 10 hr burns. Building a smaller fire and setting temp controller higher on damper does not work. Air injection for that last 1/4 of a burn would be awesome!
possibly designing a stove as well with an angle so wood slides to the front pulling coals forward possibly as the load burns. I wish I had a device inside that could shift the coal forward toward the end of the burn. Thats gunna be tough so maybe air injection is possible.
Basically the temp controller for the damper is kinda worthless as with this new model I have exceeded reasonable temps multiple times with thermostat, timer switch and the high limit and fan switch won't let it over fire. Not that I want to over fire it but its too much. This thing needs a little juice added to it. You can run the updated model Tundra 1 "Balls Out" which is best for efficiency of heat from wood, on auto pilot or with thermostat.
Once the firebox is up to temp, running "damper open" is bad for efficiency as far as capturing that heat and putting it in the house...sounds like you could benefit from a speed controller on your blower...made a big difference for me. It changes the speed of the blower to try to maintain a temp...the way mine is set up it is running full tilt by 117* duct temp...then slows down as the temps drop, finally shutting off around 93* (it is running at about 60% speed at 93*) then it restarts the blower as soon as the temp creeps back up around 10* (103*) It can be tuned for your setup...I love mine...thinking about putting one on my Drolet 1400i fan too
I've played with the fan speed on it multiple times. I want a shorter hotter burn than it can achieve as its setup. I come home to too many coals. I messed with these things enough I really feel finding some way to increase the burn of cycle would work well. Im home every 8-10 hrs and on cold days would like the higher heat with shorter burn. Hence a temp controlled method of doing this beyond just main damper. I'm thinking just a low speed blower connected to the bottom intake hole with some tubing. I have messed around with blowing air in their for lighting week coals and works very well.Once the firebox is up to temp, running "damper open" is bad for efficiency as far as capturing that heat and putting it in the house...sounds like you could benefit from a speed controller on your blower...made a big difference for me. It changes the speed of the blower to try to maintain a temp...the way mine is set up it is running full tilt by 117* duct temp...then slows down as the temps drop, finally shutting off around 93* (it is running at about 60% speed at 93*) then it restarts the blower as soon as the temp creeps back up around 10* (103*) It can be tuned for your setup...I love mine...thinking about putting one on my Drolet 1400i fan too
Heck I'll probably just drill out the bottom intake hole a little bit. I did that with a Defender stove and was happy with the results.Once the firebox is up to temp, running "damper open" is bad for efficiency as far as capturing that heat and putting it in the house...sounds like you could benefit from a speed controller on your blower...made a big difference for me. It changes the speed of the blower to try to maintain a temp...the way mine is set up it is running full tilt by 117* duct temp...then slows down as the temps drop, finally shutting off around 93* (it is running at about 60% speed at 93*) then it restarts the blower as soon as the temp creeps back up around 10* (103*) It can be tuned for your setup...I love mine...thinking about putting one on my Drolet 1400i fan too
ehh with Tundra I guess I'd open up the main intake a little rather than the lower intake.Heck I'll probably just drill out the bottom intake hole a little bit. I did that with a Defender stove and was happy with the results.
To be clear too I'm talking about for the last few hours of a burn no when the firebox is up to temp.Once the firebox is up to temp, running "damper open" is bad for efficiency as far as capturing that heat and putting it in the house...sounds like you could benefit from a speed controller on your blower...made a big difference for me. It changes the speed of the blower to try to maintain a temp...the way mine is set up it is running full tilt by 117* duct temp...then slows down as the temps drop, finally shutting off around 93* (it is running at about 60% speed at 93*) then it restarts the blower as soon as the temp creeps back up around 10* (103*) It can be tuned for your setup...I love mine...thinking about putting one on my Drolet 1400i fan too
Another solution for me, my timing and heat demand far as loading goes.. Could simply be trying the grate to raise the whole fire closer to the top thus burning the hotter smaller/shorter load I want. I find trying to burn small hot fires difficult as the fire box seems too tall. I've built towers on purpose to get loads burning closer to the top and it achieves great results. Not that I need it cause yes the i1400 inside basically drives the house up to 75 deg on a few sticks and twigs but what else am I going to to at the end of Feb?
DoubleB
Minister of Fire
I'd caution against that. Your particular setup doesn't have gravity flow, which already makes things dangerous during a power outage. Opening up that hole will make it much worse, since that hole is the main driver for combustion rate with the damper closed. And, air flowing through a hole increases a lot for even a slight diameter increase. And, it's not a reversible mod, unless you weld or plug it back up some other way.
I'm not convinced about a fan of a powered air injector to that air hole, but at least that cuts out during an outage, and you can undo it if it doesn't work. I'd start with that.
Yeah I mentioned on second thought adjusting the damper intake back to the larger cut outs would make more sense based on the function of Tundra. Your right. I think I may just try putting a grate in an burning smaller hotter loads closer to the top to achieve hotter 8 -10 hr burns at higher heat rather than 14 hr burns. I think this is what I want and realize it will consume a little more wood but will remain on the proper dialed in setup running with damper closed for most the burn. Its those last few hours of a huge load that just seem worthless no matter how low the fan is set for speed or turn on but if I load to early we of course wind up with a pile of coals half way up the fire box. lol.
Besides putting a grate in is the quickest, easiest, most easily reversible modification I will have ever done with this setup. lol.
That is exactly where the speed controller shines the most...the blower stays on low for extended times instead of just a quick blast and then off again for 5-10 minutes. That and the blower can be wired to a higher speed than would otherwise be optimal...then you can take better advantage of the intense heat available at the beginning of a burn.
And just FYI, the grate thing has been tried by several people...then abandoned...
Powered air injection in the boost air hole could be interesting...I have wondered about adding an additional rear boost air hole too...would be easy enough to plug back up if it didn't work out...
DoubleB
Minister of Fire
Yea I agree. Hate to wait to start another load when it's cold, and hate shoveling out and wasting coals.
One thing I've been doing is using the flat top of the rake to scrape the entire coal/ash mix to the front, then using the tines to push the larger coals to the rear again. This lets the coals continue to burn and give me heat on the next load, and the small coals burn out of the ashes at the front, which I scoop out before reloading. I have very few coals in my ashes this way.
I look forward to hearing your results. Recall that KARB2014 tried that and reported on pages 30, 53, and 54. He seemed to like it. I never knew how he practically scooped out ashes, though. Would love to hear what you think.
JRHAWK9
Minister of Fire
Once the firebox is up to temp, running "damper open" is bad for efficiency as far as capturing that heat and putting it in the house...sounds like you could benefit from a speed controller on your blower...made a big difference for me. It changes the speed of the blower to try to maintain a temp...the way mine is set up it is running full tilt by 117* duct temp...then slows down as the temps drop, finally shutting off around 93* (it is running at about 60% speed at 93*) then it restarts the blower as soon as the temp creeps back up around 10* (103*) It can be tuned for your setup...I love mine...thinking about putting one on my Drolet 1400i fan too
this is the cats a s s. I really would like to try this on mine.
I think the idea, for me anyhow.. is to shorten the load time some basically raise the bottom of the stove putting fire closer to the top and making it a shorter hotter burning load. Same could be done with fire brick. The only hang up I see in this is getting above the air intake hole at the bottom of the firebox. Seeing I use the temp controller and the high limit is set so low, seems likely opening the side intakes a little bit could help me achieve what I want while still maintain a larger load. Now of course this is going backwards from SBI's factory modifications to keep stoves from cracking but basically what they ultimately have done is made it run cooler period. I need to juice it back up a little. lol.
sorry the side intakes on the main damper. SBI choked them down a bit thru out their mod process.
The Kuuma kinda already has something similar...I'm not sure you would see as much difference as i did just because of the way your machine works.
BTW, I checked my furnace room temps this morn, 69* on the wall at the floor...79* on the wall at the ceiling...seems like I need to do some "preheated return air" experiments
JRHAWK9
Minister of Fire
I think it would be a bit better. As in theory the higher I turn the heat knob on the Kuuma the higher the blower speed will be and as it dies down the blower speed will come down as well. I think it will help maintain better "equilibrium" between air jacket temps and blower speed.
those temps are probably pretty close to what I was seeing before I did what I did. The ceiling temps will come down some after you start using that air.
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