Everything Drolet Tundra - Heatmax...

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I do have a baro damper installed but it only comes into play when temps outside get down in the teens, single digits or negative numbers. During negative temps if I did not have the baro damper in their the flu does over draft. Anything over -.09 or -.10 is over draft and best to keep draft around -.06 to -.08

The baro damper set properly will prevent over drafting and not block the flu like a manual damper.
ya know incase the high limit switch fails. A baro damper is a mechanical device that can save your ass in a failure.
 
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Have about 6' of single wall before it hits my chimney, then a 7" ss liner inside 10x10 clay for about 25'. No bd, have a manual damper just in case. Run her up to about 450 on the flue with an internal thermometer, 350 on magnetic thermometer on front of heat exchanger before I close the damper on stove. Flue runs at -.10 with stove damper wide open. Flue drops to 150 degrees, heat exchanger 200 and -.03 on the manometer with stove damper closed. Flames don't last more than 30 mins after damper is closed.

I'd bet your flames are going out because you only have -.03 draft. A 7" liner is bigger than called for, which reduces draft. 25' is a nice height, but maybe not enough if you have too big of a chimney. 40F isn't all that cold, either, which reduces draft. You could go ahead and replace the liner with a 6", but before that expense I'd wait for it to get cold and windy and see if your draft improves. If so, you might also find your condensation problem reduces or goes away. If so, that fairly confirms the 7" liner as the problem. Even if your condensation does not go away, then that probably points to your 7" liner.

Also, do you have too many elbows in your 6" chimney connector?

When you say the flue is 150 and the heat exchanger is 200, where are you measuring that 200F?
 
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Flue runs at -.10 with stove damper wide open
WAAAY too high!
Ran the wife and kids out of the house with fumes from paint on the first burn, not allowed to go full bore until they get away for a couple hours
The worst of it is already over with now
Flue drops to 150 degrees, heat exchanger 200 and -.03 on the manometer with stove damper closed. Flames don't last more than 30 mins after damper is closed.
Sounds awful low...depending where and how you are measuring those temps...I run ~3-350 internal pipe temp ~18" from the stove once I'm in "cruise" mode on a new load. The flames dying down is indicative of your chimney getting too cold and losing the draft (-.03" is too low 1/2 hr into the burn) sound like some stove pipe/chimney mods may be in order...but as @DoubleB said, hafta wait n see what happens when the outdoor temp drops a lil more. @Digger79 had the same issue with his draft/chimney originally...insulated 6" fixed it.
 
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Updated my model a little. If I raise the stove a little more, 2 45's and a BD should fit pretty well. I will go with single wall and insulate it. It won't be easy to remove but I will work it out. I know based on all of the advice that I will likely need a 6" liner, but I want to maximize my draft, and run the stove and see what I get for performance.

For those of you who share a duct system with a gas furnace, what did you do for backdraft dampers? Manual? Controlled? Automatic?

The stove is my primary source of heat. I set my propane furnace to maintain 55F - in case I unexpectedly do not return home for some reason. For that reason, I don't want manual backdraft dampers. I am considering the more expensive automatic type type.
 
Hey all, got the Tundra installed this week. Thanks for all the helpful posts! This thing def has a learning curve to it. Puts out great heat for long amounts of time with less wood.Sbi sent me the firebrick mod which was nice, would have never known about it if it weren't for this blog. Averaging about 40 in central Ohio so I haven't cranked her up yet. Ran the wife and kids out of the house with fumes from paint on the first burn, not allowed to go full bore until they get away for a couple hours. Have about 6' of single wall before it hits my chimney, then a 7" ss liner inside 10x10 clay for about 25'. No bd, have a manual damper just in case. Run her up to about 450 on the flue with an internal thermometer, 350 on magnetic thermometer on front of heat exchanger before I close the damper on stove. Flue runs at -.10 with stove damper wide open. Flue drops to 150 degrees, heat exchanger 200 and -.03 on the manometer with stove damper closed. Flames don't last more than 30 mins after damper is closed. Burning two year old ash with about 15% moisture. 5 logs fill up the firebox, might need to be split smaller. Also having an issue with condensation dripping from pipe, only 2 days into burning. Had good amount of coals after 12 hrs which was nice. What's your thoughts?

I winter 5 logs might work, now you will need to split them at least in 1/2 if not 1/3.
 
For those of you who share a duct system with a gas furnace, what did you do for backdraft dampers? Manual? Controlled? Automatic?

The stove is my primary source of heat. I set my propane furnace to maintain 55F - in case I unexpectedly do not return home for some reason. For that reason, I don't want manual backdraft dampers. I am considering the more expensive automatic type type.

My wood furnace shares the supply ducts with my LP furnace. It does not share the return ducts with my LP furnace. I use an open staircase in the middle of the house for return air. I have a gravity damper in the plenum of my LP furnace to protect back flow though the LP furnace. I also have a spring open/powered closed electric damper in the wood furnace supply duct between the wood furnace plenum and main house supply duct. I have it wired in such a way the powered damper will remain open in all situations except for when the LP blower is the only one running (in summer and winter), then it will close to prevent back feeding the wood furnace. In all other situations it remains open. I needed it to remain open with no power in case of a power outage. This allows me to run both the LP blower and wood furnace blower at the same time if I ever need to...or at the end of a burn cycle on a very cold morning when the wood furnace blower is cycling and the LP thermostat calls for heat. Having the ability to do this allows me to keep the LP thermostat set at whatever temp I want and not have to worry as both furnaces can run in harmony with each other.
 
Ok so if you 3-4 hours and want to insulate you tundra here's the how to:
DEI high temp spray adhesive
Aluminum tape
Cool it 72x48 Thermal blanket can be had on Amazon. It's enough to insulate both sides and top. Cut it in half 36inches and then cut it to 38 inches. Save your left overs for the top. Don't forget to trim away from the damper control rod. I also removed the screws and heat shield before spraying and installing the blanket. I then reinstalled the heat shield and all the screws. I will post my temp differences once I start a fire.

Fire started: here's the data...

Fans kicked on in 8 minutes. I set the timer to 20 minutes. The top of the furnace was warm to the touch just prior to the fans kicking on. I grabbed my IR gun and took these measurements. The outside insulated case is measuring 84-86 degrees fan running on 2. The front face is at 450 degrees damper closed. The uninsulated section in the rear of the furnace is measuring about 114-118 degrees. So the insulation blanket is making a pretty big difference. It heated up pretty darn fast! Oh and draft was about .07. Duct outlet temp is about 120-125.
I like this idea.. messed around with rock wool layers simply on top of the plenum before myself.. Curious about what you have done here. How high of heat can that insulation take as well the cellophane foil on the surface of it? that heat exchanger can get pretty damn hot and I'd think any thermal blanketing not rated up to 1200 deg or better could either melt of simply not be efficient. Standard insulation looses its insulating properties when over heated. Just curious about the heat capacity of the thermal blanket you are using. Id be nervous with anything but rock wool inside that stove.
 
I think I would be nervous about any insulating mods. Just seem that if it doesn't have insulation, it wasn't designed to be run with it which might set up for future trouble with some things getting too hot from no air wash or being able to radiate, etc..
 
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The cabinet on the Caddy line is insulated...very similar (but not identical) unit, but yeah...you are always assuming some risk when doing any mod...and some people just plain shouldn't do mods at all...this is fire "inside your home" that we are playing with after all...
OK, that is the end of my Public Service Announcement ::-)
 
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Id say likely it can be done safely if your experienced enough to pay attention to all the temps, snap switches and be ready to make changes to the snap switches and such. I was just curious if high temp insulation like rock wool was used in the caddy. I feel basic insulation with cellophane would likely melt above that heat exchanger.
 
BTW Brenndtomu my false reading wound up being a cheap probe. nothing wrong with the my pin controller. I found out I wound up with a 500 deg max temp probe and promptly ruined it to where it barely worked anymore at all. lol. Sooo being one that hates to order stuff of the web, and very impatient I ran to menards an bought a multimeter that measures temperature as well with a probe up to 1500 deg. Incredibly accurate. I wound up wiring the probe (k) type that plugged in to the multimeter to the mypin and BAM! Dead on MyPin readings. So for some just looking for a good way to get accurate flu temps w out order the wrong probe like I did.. Multimeter from Menards. I am going to try and order another J type probe pre wired like the one that came with the mypin this winter though.
 
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If it gets up to .09 now, wait till it gets cold out with a hot fire. I believe a bd is a must have, good protection too. .09 is 50% more than SBI recommends isn't it.
Yeah BD is a good idea. Someone on here tried to tell me a 15' chimney wouldn't need a baro but when it hits teens and single digits the baro and desired draft readings proved them dead wrong. I have outstanding draft likely due to the black single wall connector being basically 1 45, the baro damper and thats it. about 18-20 inches right into the 6" SS insulated chimney. It really sucks :)
 
Yeah BD is a good idea. Someone on here tried to tell me a 15' chimney wouldn't need a baro but when it hits teens and single digits the baro and desired draft readings proved them dead wrong. I have outstanding draft likely due to the black single wall connector being basically 1 45, the baro damper and thats it. about 18-20 inches right into the 6" SS insulated chimney. It really sucks :)
not to mention when I load a brush fire of locust and hickory to get fast heat my draft can take off and over draft so the baro helps there too.
 
I think I would be nervous about any insulating mods.

I agree. 1/4" insulation leaves 3/16" max for airflow, significantly less than stock, especially if things sag over time. I don't know if it's a problem, but I don't know it's ok, either. I've never had a power outage with mine, but if/when it happens I want all the passive heat removal I can get.

The picture in post 1751 has insulation covering the overtemp and fan snap discs, which would cause a major problem if not corrected.

Most important to me is that I'd be surprised if there's anything to gain from it. The furnace sides are about room temperature anyways so insulation won't help that. The top gets warm and loses some heat, but it's a much smaller area than all the ductwork most of us have exposed. If I really wanted to do something, it's probably safer and easier and more effective to insulate some of the ductwork.

I applaud the intent, not trying to bash anything, just giving more food for thought.
 
I will put money on the fact of no insulation is just a cost savings measure. There is a reason that a caddy costs a lot more than a tundra even though they are basically the same. This whole line was designed for affordability.
 
I'm sure you're right on the cost savings. Still, I ran the math that it only takes the first 1 foot of 8" round ducts (x2) coming off the top of our Tundras to equal the same sq footage as the entire top of the Tundra. We have far more ductwork surface than furnace top surface losing heat, so there's far more and simpler opportunity to save heat by insulating ducts than inside the furnace.
 
I'm sure you're right on the cost savings. Still, I ran the math that it only takes the first 1 foot of 8" round ducts (x2) coming off the top of our Tundras to equal the same sq footage as the entire top of the Tundra. We have far more ductwork surface than furnace top surface losing heat, so there's far more and simpler opportunity to save heat by insulating ducts than inside the furnace.

Did he insulate the top? I dont think that would help much, also doesn't the new tundra have a plenum instead of the round outlets. The 4 sides insulated should help a good deal.
 
Ok I have my stove installed. I am planning to build one of the temperature controllers like you guys have documented. For now I am using the factory design.

I lit my first fire this evening and am babysitting it. I have a few basement windows open and am ventilating the basement just to reduce the fumes. I have not plumbed the stove into my duct system as I didn't want to stink up the house.

About half an hour into the burn, with the blower running, there were 2-3 small embers and even some particles of ash that blew out of the ducts. I haven't seen anthing for the last hour but still. This is obviously a huge concern and fire hazard. I have been watching closely and have not seen anything else blow out.

What do you guys think? I'm wondering if from it being a display model, if there was some debris that got into the stove and burnt/blew out but I don't want to speculate.
 
If it was a display model then it likely needs the ash pan mod done. This was the first issue they had with these things. SBI will send you one for free if it still needs it...and it is pretty easy to put in.
As you said, it could have been accumulated dust bunnys that were already in there too. Since you have not hooked up the ducts yet, then it would be real easy to remove the top and side panels to inspect all the welds...mine had an issue and I know of 1 or 2 others that had missing and/or incorrect welds. Use a bright light inside and outside the HEs to look it over carefully.
 
Wow, that is a ton of work for a "volunteer" Someone is very passionate about these units. The only suggestion I can offer is to maybe bring up in the 1st 5, The ash pan issues on the 1st models. This is a life and death issue with these units and as far as we know SBI has not reached out to the owners of the deadly design flaw. Now they are selling display models that may well be the same death traps as the original. Maybe just a warning in the beginning about the deadly start of the Tundra.


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I recall now the mention of the ash pan issues. Can someone elaborate what the fix is? I had contacted SBI and requested any and all updates or revisions. All they sent was the fire brick.

There is also updated electrical components and locations, correct? I wanted to bring this thing up to date
 
Ok I have my stove installed. I am planning to build one of the temperature controllers like you guys have documented. For now I am using the factory design.

I lit my first fire this evening and am babysitting it. I have a few basement windows open and am ventilating the basement just to reduce the fumes. I have not plumbed the stove into my duct system as I didn't want to stink up the house.

About half an hour into the burn, with the blower running, there were 2-3 small embers and even some particles of ash that blew out of the ducts. I haven't seen anthing for the last hour but still. This is obviously a huge concern and fire hazard. I have been watching closely and have not seen anything else blow out.

What do you guys think? I'm wondering if from it being a display model, if there was some debris that got into the stove and burnt/blew out but I don't want to speculate.
Im guessing so don't take this as a professional opinion. lol.. I doubt a hot ash stayed lit and pulled thru the dust pan and came out the hot air duct. Yes the old models sucked in some air but thru a fine crack packed with ash.. I ran my first model with the ash pan sucking dust and from what I could see it basically plugged itself with ash lol and quit drawing. Anyhow Im with y'all on the debris in the hot air or plenum top, loose chafe inside.. did you get all the cardboard out? lol. likely small pieces/scraps of paper, dust, lint or cardboard Id think could be in the plenum as two holes are always open. I think the ash pan problem was maybe overrated cause I had it and no problems really from it. I have a latest model now.
 
@Digger79 I just thought it was more likely that something from the fire box made it out and was glowing red, rather than a dust bunny getting red hot. Regardless, I was up most of the night and slept on the couch near the stove with a few windows open.

Like you guys, I have no intention of using the ash pan at all. I took the wing nuts off and opened it up this morning, there was dust but that's it.

Wasn't there some changes made in regards to the fan control? I thought I recalled where they moved the location of the fan control switch, and also maybe the temperatures?