Everything Drolet Tundra - Heatmax...

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Nope no tundra ll for me, this time it's go big or go home.:ZZZ
I don't blame you. I got the Caddy because I always heard it was better to run the dog snot out of a smaller stove or furnace vs letting it idle. That is great until you have a cold snap and can't get any more snot out of the dog. ;)
 
With all of the talk about blower speed controllers I figured it would be a good time to post this description of the one that I recently built for my Tundra using the factory motor and the high and low speed lead leads from the motor. I ran the hot lead to the motor to the com on a relay, high to the motor to NC and low to NO on the relay so it will fail to high. The relay is connected to a temp controller that is monitoring the air temp coming off of the furnace. Switches to high at 105 and back to low when the temp drops to 100 (for now).

Enjoy!
 
I don't blame you. I got the Caddy because I always heard it was better to run the dog snot out of a smaller stove or furnace vs letting it idle. That is great until you have a cold snap and can't get any more snot out of the dog. ;)
What are you currently heating with the caddy?
 
With all of the talk about blower speed controllers I figured it would be a good time to post this description of the one that I recently built for my Tundra using the factory motor and the high and low speed lead leads from the motor.
Good idea! It is basically what they do with the Max Caddy, it is not a 'drive' or 'inverter' it is only switching wire...

I hope SBI will add more 'control' over their speed controller... Max Caddy is locked at speed 2 until it reach 140F in the plenum, than it speed up to what I think is speed 4, than close the damper and speed up to 6 when it reach max temp (don't remember temp)... I rarely reach 140F with wood, not the way I run it... If it happen, speed 4 will cool the plenum pretty quickly... If I had more control over that controller, I would start it at speed 1, boost it at speed 2 when it get to 120F and back to speed 1 below 110F... It would probably solve my frequent cycling problem... So, for now I don't really enjoy that speed controller I probably paid lot for.. it is always at speed 2...
 
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In my ongoing email convo with SBI I asked them how to measure, and what kind of temps I should be expecting for "normal operation"...this was their response...

"In terms of venting and internal combustion, they are like a big wood stove. Temperatures below 800F, even if continuous, do not cause a problem for steel. Normally, if you were to put a thermometer on the flue, you’d get approximately 350F to 550F in the flue during normal use. You could go as high as 700F during start-up, but not much more.

A unit like the Tundra/Heatpro, if operated normally, with dry cordwood and normal average flue temperatures of 350F to 550F can be operated continuously during winter."


I think they mean internal flue temps, because that's what I had been referring to in my email. I guess I am finding it hard to believe 700* wouldn't cause problems...(for Tundra/Heatmax) I think there are a few people here that have had cracking issues and flue temps that never hit 700. And 700* would definitely be impossible to sustain for long...the firebox would fill up with red hot coals right quick!
Their recommendation of 350*-550* sounds like a good range to me. Since I have welded my cracked heat exchanger up, 550* will put out a ton of heat for me (that's where flue temps were when I found my damper stuck open the other day...when I had 154* duct temps)
And speaking of duct temps, my wife even noticed a difference after I fixed the HE, she said today that she has noticed the register in our sons room tends to runs warmer...and she normally never notices these things...
 
What are you currently heating with the caddy?
We are currently heating a 2236 sq ft ranch in zone 6a / 5b.

We put on an 832 sq ft addition a few years ago that is insulated really well. The other 1404 sq ft is insulated moderately well but it also has cathedral ceilings. The 832 sq ft basement is also heated, but that is mostly from the excess heat from the furnace.

When I bought the Caddy about 5 years ago it was rated for 2000 sq ft. Now I think it is only rated for 1700 sq ft. I think you can see a trend with PSG in this area. ;)
 
Sorry everyone I was not able to get the plenum installed. We finally had are first good snowfall and the kids (also me) wanted to go out and play in it. I did get sick of the coaling issue and went back to using the grate. I now no longer have any coaling issue, My house after a reload will jump up to 75 settle in a 74 and hold that for 5.5 -6 hours. Then it will drop to 73 and the thermostat will open the damper and burn the coals for another 2hrs and not let the house drop below 72. All but a hand full of coals will be left. This is with 10 deg weather with strong winds. Normally with that kind of weather I would have a firebox of coals and the house would drop to 69-70 while I would try to reduce the coals. In order to use the grate I have to reduce the hole size on the primary air damper to about half the size. I'm talking about the hole in the damper flap when it is closed. Also I'm still running the secondary air about 50% closed off. To be hones I'm kind of jealous of those of you that have yours cracking. Mine must have been built tough because it will not crack. I wish it would so I would have a reason to upgrade to a max caddy or heatmax. I will try to make time sometime soon to install the plenum. Does anybody happen to have a picture or anyway to better describe the "wings" that the caddy has?
 
Is that what you means by 'wings' ?
It is from a Max Caddy

IMG_1233.JPG IMG_1235.JPG IMG_1234.JPG
 
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Is that what you means by 'wings' ?
It is from a Max Caddy

View attachment 173162 View attachment 173163 View attachment 173167
Right below the HEs, on the side of the air jacket, there are air deflectors (wings) to make the air go under and all around the HEs. The newer Caddys also have one in behind the firebox, under the center HE, to deflect the air forward instead of just shooting straight up, without much opportunity to pick up some heat along the way (if it just went straight up)
 
Here is the latest on the warranty. I'll start by saying I am very pleased with the service I am getting from both SBI and L&M Fleet supply. First off SBI is taking the unit back. In turn I will receive a full refund. L&M called me last night to make sure everything was going to my satisfaction. I asked SBI if I could keep the unit to finish off the season seeing how I have a bit of money and time invested. They said no problem lets us know when you are ready in the spring. To me this is first class service and I could not ask for anything more. Hats off to L&M and SBI they are making things right by me. I highly recommend everyone to purchase from L&M if possible. Seeing how SBI is standing behind the tundra and providing great service I will be giving them more business by purchasing a Max Caddy. I also asked SBI for a replacement baffle that goes ontop of the secondary tubes
I think I cracked it by loading wood. I told them I would pay for it seeing how they are willing to take the unit back. They replied I'll send you one free of charge. I don't think they had to do that at all. So for now I'll keep burning the tundra and when the season is done she'll be heading north of the border.
 
Here is the latest on the warranty. I'll start by saying I am very pleased with the service I am getting from both SBI and L&M Fleet supply. First off SBI is taking the unit back. In turn I will receive a full refund. L&M called me last night to make sure everything was going to my satisfaction. I asked SBI if I could keep the unit to finish off the season seeing how I have a bit of money and time invested. They said no problem lets us know when you are ready in the spring. To me this is first class service and I could not ask for anything more. Hats off to L&M and SBI they are making things right by me. I highly recommend everyone to purchase from L&M if possible. Seeing how SBI is standing behind the tundra and providing great service I will be giving them more business by purchasing a Max Caddy. I also asked SBI for a replacement baffle that goes ontop of the secondary tubes
I think I cracked it by loading wood. I told them I would pay for it seeing how they are willing to take the unit back. They replied I'll send you one free of charge. I don't think they had to do that at all. So for now I'll keep burning the tundra and when the season is done she'll be heading north of the border.
That's awesome! I had an issue the first year on mine that caused the back to deteriorate. I believe it was from sitting in bad storage. Anyhow, SBI took care of me and sent a new firebox, along with firebrick, and other replacement parts. The furnace was branded a usstove, but since SBI built it, they took care of things. They even drove here from Canada to talk to me and take pics. I've never had an issue with their customer service. Can't wait to hear about the Max Caddy. Maybe someday I'll upgrade to something larger. Glad to hear they are taking care of things.
 
Good idea! It is basically what they do with the Max Caddy, it is not a 'drive' or 'inverter' it is only switching wire...

I hope SBI will add more 'control' over their speed controller... Max Caddy is locked at speed 2 until it reach 140F in the plenum, than it speed up to what I think is speed 4, than close the damper and speed up to 6 when it reach max temp (don't remember temp)... I rarely reach 140F with wood, not the way I run it... If it happen, speed 4 will cool the plenum pretty quickly... If I had more control over that controller, I would start it at speed 1, boost it at speed 2 when it get to 120F and back to speed 1 below 110F... It would probably solve my frequent cycling problem... So, for now I don't really enjoy that speed controller I probably paid lot for.. it is always at speed 2...
You realize on a max caddy The speed of the blower can be adjusted . The factory setting I found to be just right . Far better than the tundra single speed which I also have owned. Of coarse each persons ducting and setup varies
 
To me this is first class service and I could not ask for anything more.

That's really great to hear. Not only for your sake that you're taken care of, but also great to hear that SBI is earning a top-notch reputation. And going above and beyond (like your baffle). They have followed through very well for me too, even tracked me down once and sent me parts before I installed or registered the furnace and knew the snap disc was broken. It's stuff like this that gives me a lot of patience even though the furnace has cracking problems and SBI doesn't seem to answer technical questions thoroughly. If I had to get rid of my Tundra today, I'd still start with SBI (although a Caddy or Max Caddy until the Tundra or Heatpro are vetted.)
 
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You realize on a max caddy The speed of the blower can be adjusted . The factory setting I found to be just right . Far better than the tundra single speed which I also have owned. Of coarse each persons ducting and setup varies

Go to max caddy pricing thread for reply, I think I used too much of that 'tundra' thread
 
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Well I set out to install a plenum on Tundra today...got a little sidetracked, we'll see how this turns out.
As part of my plenum install I wanted to keep the air flow through the furnace air jacket from "short circuiting", going up the back of the firebox, right up over the HEs and out. Very little contact time with hot things.
The longer I studied the issue and thought about the airflow through this thing, the more I have become convinced that I want to block most of the huge open space (highlighted in red) on the back side, channel the air right up to the factory side air deflectors.
DSCN1325.JPG
DSCN1332.JPG The backside of the firebox, from the left side. Wide open spaces back here...I highlighted the blower in green.
DSCN1336.JPG Here's what I came up with, it is just setting on the HEs here.
DSCN1338.JPG The new air deflector in place, from the left side.
DSCN1344.JPG I also decided to make a deflector to channel the air in the front corners around the HE cleanout box.
DSCN1347.JPG

DSCN1342.JPG
DSCN1348.JPG Just clipped onto the factory air deflector using a couple short pieces of S clip
DSCN1351.JPG

DSCN1352.JPG Complete
DSCN1353.JPG Now almost all the air has to get up close and personal with hot things. I know these pics make it look like I have things really choked off, but believe me, it is not as tight as it looks, there is plenty of room for air flow. There is still some air able to come up past the deflector in the back as I kept it 1//4" - 3/8" up off the firebox and left a 1/4" or so gap around the HEs too.
I think this is gonna make a real difference, I decided to put the old top back on and use the same 3 ducts connections that I have been using, just to compare...so plenum postponed again. It's pretty warm here right now, I'm not even sure when I will be able to fire up and try this out! :confused:
 
I like the shield ideas I'd add hi temp insulation too if space allows . My max caddy is full of shield deflectors and insulation inside instead of the tundras empty tin box design .
 
Looks great, I wonder if this is the reason SBI does not recommend removing the factory top and installing a plenum.
With the lack of deflectors and a more open plenum style top even less heat might be transferred. I'm hoping the defectors + plenum will be the ticket for optimum heat transfer.
 
Nice work B I'm following this closely at some point I may give the heatmax another shot so I'm very interested in any mods that will help....One question , in picture 2 what is that sq tube I see down in there I noticed that looking down into mine "without the top removed" couldn't figure out what that is for or does...anyhow good stuff

PS ..looking at it again maybe that's what makes contact with the floor ?
 
tundras empty tin box design
That's a good description of it, a tin can with a firebox sitting in the middle of it. The two side air deflectors are really the only thing in there to actively control air flow.
I wonder if this is the reason SBI does not recommend removing the factory top and installing a plenum.
Well, I dunno. When I went to research this subject at the local dealer a few weeks back, I was a little surprised to find that the Caddy is almost identical under the air jacket, except the Caddy has the reflective insulation like @lexybird mentioned his Max Caddy has. Oh, and the little deflector behind the firebox, under the center HE, Tundra just has a bracket there to support the HE, no "wing".
To be honest the airflow through the Caddy is likely very different because of not having the blower pushing air directly into the back of the huge ash pan that the Tundra has. The Tundra firebox is basically "sitting" on the ash pan (not structurally it isn't, the firebox is actually supported by the front panel and the two rear legs) whereas the Caddy has a small ash pan, and under that is wide open. (which allows room for the oil burner option)
I'm following this closely at some point I may give the heatmax another shot
You mean your old one, or a new one?
One question , in picture 2 what is that sq tube I see down in there I noticed that looking down into mine "without the top removed" couldn't figure out what that is for or does
PS ..looking at it again maybe that's what makes contact with the floor ?
Yeah, that is one of the two firebox support legs
 
You mean your old one, or a new one?
the old one , if heat production can be improved with a plenum and a few mods... and a little more work on the house maybe I could get it to do the job .... I like the new furnace there is more than enough hp to heat this place but with warm temps say in the 30's it will give more than we want.. Some days I let it go out...The other thing I worry about is my wife running it . She puts wood in but as far as adjustments to the draft and such, that going to take some time... The FChief will get hot fast and over fire is a concern...so I don't let her mess with the adjustments.....
I was shooting for something that was easy for her to run when we got the heatmax the FC is old school and maybe a step back from wife friendly ..lol
anyhow enough of my sidetracking....keep up the good work B
 
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I was shooting for something that was easy for her to run when we got the heatmax the FC is old school and maybe a step back from wife friendly ..lol
I was telling my wife just the other day, the Tundra is the easiest wood burner to run that I have ever used, especially with the temp controller added onto it. Open door, rake coals forward, load wood, close door, set timer done. Only slightly more work building fire from cold stove...
And it really is a pretty clean burner...after installing the Tundra over at my sisters place I have not had to clean the chimney all winter so far (checked it once) When she was using the old Yukon Big Jack in its stock form the chimney needed cleaned once a month or so
 
I was telling my wife just the other day, the Tundra is the easiest wood burner to run that I have ever used, especially with the temp controller added onto it. Open door, rake coals forward, load wood, close door, set timer done. Only slightly more work building fire from cold stove...
And it really is a pretty clean burner...after installing the Tundra over at my sisters place I have not had to clean the chimney all winter so far (checked it once) When she was using the old Yukon Big Jack in its stock form the chimney needed cleaned once a month or so
There are no doubts there once you get the Heatmax fired up you can walk away....I took my wife down today and went over the air controls on the FC... I have a Dwyer manometer mounted to the side of the FC, showed her how that works...Next I'll walked her through a cold fire up and the needed adjustments and why and what for....

I did buy a temp controller for the FC but it runs between 350/450 at idle "measured just after the stove collar" by the time it drops below 300 the wood is pretty much gone...