Everything Drolet Tundra - Heatmax...

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Hey Digger, those numbers make me wonder, are you sure your ductwork gives you enough cfm to carry heat out of your furnace? That temp rise is 2 or 3 times as much as my Tundra setup. Not saying that mine is right, but that sure seems hot.
yes. Blows harder than my gas furnace. Duct temps are not as hot with the Updated model as the fan comes on sooner. I have to admit those temps where takin on the 1st unit. However my ducts still get pretty darn hot. Def cools the plenum in a hurry. I have adjusted the snap switch with a few spacers to push it back to turning on around 400 deg flu temps as factory setting it was coming on before plenum was even warm hardly. now I can feel the top of the stove get hot to the touch just before the fan kicks on. I'm happy with the fan temp setting as Im not blowing cold air anymore. I have a 12" air return line that is only about 30 ft or so of flex. Yes CFM's are very high thru my duct work now. Im not sure why I get such hot air other than I burn the furnace pretty hot most the time now. It seems I can't hardly over fire this model. I have however gotten the flu up to 960 deg for a few seconds and still no cracks, warps failures nothing. Commonly 720 is the hottest my flu see's upon surge before I let temp controller take over. I do burn top down fires with def give pretty hot air and pretty much right away. I've also learned to stack the wood loose and tall. I am going to get a grate for warmer weather so I can burn smaller fires closer to the top. One thing I have learned with Tundra's firebox is even when fire box temps are high and fire is hot the distance between the top of the fire/coals and the plenum can kill our heat exchange. Once tundra is done with surge and goes into return duct temps are warm at best. The fan cools the furnace almost instantly unless the fire is ragin hot. Funny you would ask bout this cause actually I am having the opposite problem hence dialing back the snap switch with shims and considering lowering the fan speed here soon. Its on High-high. I had CFM issues at first but after replacing a ton of flex with smooth and going to the lightest filter I can buy, the air comes screaming out of my ducts now and hits you in the face 5 ft away. I have not measured duct temps on this newer model and I am sure they are lower however def very hot air 10-20 ft out still and at the registers I would guess I am getting around 120 deg during most the hotter stage of burn and around 140 on surge but I may be off. I'll grab a heat sensor gun and check it out an repost here soon. I haven't smelled hot ducting since I added smooth duct and updated tundra really. A few times the smooth pipes got hot and smelled a little when I accidentally left door cracked and a few times when I simply pushed the stove to its max. SBI said if I cracked it again they would replace so I have been pushing the thing.. no cracks. The firebrick around the door(I have a better lining than factory there) and the HE being relieved at the cut out pretty much solved those problems.
 
Hey guys! I thought I would sneak into the thread since I just picked up the 1st gen Tundra at Menards (very well could of been the last one in the state of Michigan) for $799.00!!! I have been lurking this thread for the past year or so, so I am aware of the cracking issues. I will be picking up the unit on Monday so I am not sure if they will have added the door firebrick at this point or not. If not, I plan on doing this myself. I guess my biggest concern right now is the 8 inch ducting from the unit to my current plenum, and also the return line.

My first question that relates to the 8 inch supply lines is: Would it be OK to run a 8 inch solid HVAC galv pipe about 30 inches or so up from the unit and then elbow into flex duct and run that the rest of the way to my plenum? I will be adding pictures soon of my current LP and plenum set up.

Secondly, Will I be OK not tying into the current return air plenum for about a year or so until I make more space to do so?

My house is smaller, 1300 sqft 2 story with a basement. Chimney will be an exterior 5.5 inch SS lined at 30ft. in height. I will be using a BARO.
Avoid as much flex as you can possibly pull of. I started with all flex other than the first 5-10 ft of solid coming out of the plenum. As hot as my ducts have gotten I recommend a minimum of 20 ft from the plenum. The main reason I say avoid it though is it kills your airflow. Something like 5ft of smooth duct has the same friction as 1 ft of flex. its pretty bad. The ridges in the flex really slow the air down. After replacing most of my flex with solid as budget and time allowed my CFM's went thru the roof compared to before. The flex was just a cheap quick way to get it running. I would go totally solid if possible.
 
Hey Digger, those numbers make me wonder, are you sure your ductwork gives you enough cfm to carry heat out of your furnace? That temp rise is 2 or 3 times as much as my Tundra setup. Not saying that mine is right, but that sure seems hot.
I should add/impact the point I did measure duct temp near 300 with a probe on the old tundra unit about 10-20 ft away from plenum upon highest surge of burns. I have not accurately measured register temps nor current duct temps with a tool but honestly guessed at those temps. Likely once I get an actual temp measuring tool on the registers and current duct I will find my numbers to be lower than I think. No doubt however it gets much hotter than my gas furnace at the registers. I can say that. I do not get that hot heat very long at all however. Again I will get a heat sensor gun/ remeasure things and repost. probably estimating high. I do burn my tundra hotter than others I think as I find the hotter I burn it rather than letting it reburn all the time the warmer my house is at the end of a burn period. I've been thinking about adding a return intake in the garage to reclaim some of that heat. At times my garage is 80 plus degrees lol. Not sure I need all that heat out there.
 
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So I talked about adding a temp controlled air injector for burning a hotter fire during the last hours of a burn and shortening up the burn cycle from 14 hrs to 8-10 hrs instead at higher temps. I plan to play with this idea late this winter. This also can assist in starting fires quite nicely. If you haven't seen the Green Start heat coil that injects 1400 deg air and starts fires with hot air, you should check them out. pretty cool. Load stove entirely, shut door, push ignitor button and walk away. Quadrafire I believe has them in their stoves. As well something I have become interested in is adding on a battery powered back up generator. We all know the concerns over power loss especially if one is not home when it happens. I have seen some back up generators these days that charge while the power is on and can provide easily enough power for like 7 hrs to run the tundra in a power outage. These units are pre set an will turn on with power loss and power anything you plug into them. Power will run thru while charging. I think this would be nice addition to the Tundra setup and make me feel better as I have power outages at least once a winter. Supposedly these unit can run refrigerators and a few other appliances for around 7 hrs on battery. I would guess just running tundra it would easily perform to its spec. We all know consumer items are never as good as they claim especially battery stuff.
 
Firm believer here in regular frequent HX cleanings. I don't have a Tundra - or a furnace. But my boiler has tubes, and Sunday mornings seem to be the time they get brushed. Seems to fit in with the rest of the lazy day, only takes 5 minutes or so and I usually do it between a couple other puttering things I put off all week. And a coffee.
Can agree there just did mine after about 1.5 cord! Also figured out my primary air damper plate problem. Seems mine is slightly warped and straightens out when heated up.
 
Hi guys,

The damper on my Tundra will not open. I checked the linkage rod at the damper and the motor, and nothing is amiss. Did the damper motor go bad do you think? This is the second season this unit will have been in operation. I did install a temp. controller, so it runs the motor a little more, but not an inordinate amount. Thanks for any feedback.
 
My damper motor was replaced under warranty after about a year. It started off weak, like it was skipping, then failed completely. SBI was good about sending a new one.
 
Hi guys,

The damper on my Tundra will not open. I checked the linkage rod at the damper and the motor, and nothing is amiss. Did the damper motor go bad do you think? This is the second season this unit will have been in operation. I did install a temp. controller, so it runs the motor a little more, but not an inordinate amount. Thanks for any feedback.
If you can check for power at the motor, that will tell the story for sure. If you turn the manual switch to "on" when the firebox is not hot, then you should have 24V AC power (and ground) at the motor. If you have that and it is not working then yes, its bad.
 
Hi all, I have been considering purchasing a Tundra from Menards as they now are closing them out at a cost of about $800. I am looking for a replacement to my wore out Hot Blast furnace for my shop area. It is not huge, 24' deep x 40' wide x 9' ceilings. The chimney is a very standard concrete block chimney with a 9 x 9 clay flue tile lining. I have been looking at the Tundra for about three years. I have been reading a lot of the information on forums and this thread specifically (thank you for all of the great info). It sounds like there are some modifications or add ons that some have made. It also sounds like a different animal as far as running compared to the Hot Blast with smaller very seasoned splits (which would not be any issue). I certainly would not be running this every day or non-stop, but curious if you all would think it would be a reasonable unit for this application. For that price, I am strongly considering going this route. Thanks in advance for any thoughts you may have.
 
Hi all, I have been considering purchasing a Tundra from Menards as they now are closing them out at a cost of about $800. I am looking for a replacement to my wore out Hot Blast furnace for my shop area. It is not huge, 24' deep x 40' wide x 9' ceilings. The chimney is a very standard concrete block chimney with a 9 x 9 clay flue tile lining. I have been looking at the Tundra for about three years. I have been reading a lot of the information on forums and this thread specifically (thank you for all of the great info). It sounds like there are some modifications or add ons that some have made. It also sounds like a different animal as far as running compared to the Hot Blast with smaller very seasoned splits (which would not be any issue). I certainly would not be running this every day or non-stop, but curious if you all would think it would be a reasonable unit for this application. For that price, I am strongly considering going this route. Thanks in advance for any thoughts you may have.
Hi Erik, the Tundra doesn't have the "raw horsepower" that the HB has (kinda like the "tortoise and the hare" thing)but I think you'll find it will do a nice job in this space especially since the unit (I assume) is right out in the space where you are heating...a lot of radiant heat to be had off the front of these things. It will sure enough use less wood and burn cleaner than the HB!
 
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Hi Erik, the Tundra doesn't have the "raw horsepower" that the HB has (kinda like the "tortoise and the hare thing")but I think you'll find it will do a nice job in this space especially since the unit (I assume) is right out in the space where you are heating...a lot of radiant heat to be had off the front of these things. It will sure enough use less wood and burn cleaner than the HB!

Awesome - thanks so much for the reply. Yes, I think radiant heat would be an additional benefit. One of the things that I was most excited about with the Tundra is the fact that there is glass in the door. Being able to see the fire would be very nice. Thanks again!
 
Awesome - thanks so much for the reply. Yes, I think radiant heat would be an additional benefit. One of the things that I was most excited about with the Tundra is the fact that there is glass in the door. Being able to see the fire would be very nice. Thanks again!
Take it from me who replaced my hotblast. This thing is a totally different animal. I thought i was a decent wood burner then I had to throw everything out the window I knew about how to operate a wood furnace and learn again. Beauty is now I don't get up religiously at 2am to load the old red beast. Can't say I miss it. That hotblast always scared me a little bit!
 
Just sent all info to sbi they want about my damper being warped. Now it's my turn to test their customer service and warranty
 
Take it from me who replaced my hotblast. This thing is a totally different animal. I thought i was a decent wood burner then I had to throw everything out the window I knew about how to operate a wood furnace and learn again. Beauty is now I don't get up religiously at 2am to load the old red beast. Can't say I miss it. That hotblast always scared me a little bit!

Thanks for the info! I have enjoyed reading all of the posts on how it operates and how different it is. The hot blast has done its job for many years, but this one also scares me now. I am thinking the Tundra will be a good way to go! Thanks again.
 
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Tundra was delivered and schlepped down the stairs today. Still waiting on Northline to send the chimney liner.
Contacted SBI about sending me the upgraded frontal fire bricks and they said all they need is a invoice copy and it will be on its way. Serial on this unit is 17## an early 2014 model.

Anyone see an issue of running one of the 8 inch supply pipes about 13 foot or so and tapping in down the plenum? I think I may insulate the longer run.
 
Tundra was delivered and schlepped down the stairs today. Still waiting on Northline to send the chimney liner.
Contacted SBI about sending me the upgraded frontal fire bricks and they said all they need is a invoice copy and it will be on its way. Serial on this unit is 17## an early 2014 model.

Anyone see an issue of running one of the 8 inch supply pipes about 13 foot or so and tapping in down the plenum? I think I may insulate the longer run.
Well Id look to Double D, Steely Dan, and Brenndatomu for solid highly experienced advise. Most everything I've learned about wood stoves period and Tundras dribbled down from those guys on here. I would say one 8" output would restrict the air flow too much(cfm's) and not allow the tundra to properly strip heat from the plenum. U would likely get hot air longer but I don't think you would get as good of volume of hot air and risk over heating the plenum. The biggest problem I see with this though is lose of volume of heated air. I would guess twice the amount of hot air is worth more than half the amount of slightly hotter air slightly longer. I do not think the increase in temp and time of delivering hot air would be enough to over power the advantage of the volume and removal of air from the plenum the two 8" outputs would provide. And it will certainly void the warranty.. not that most of us on here haven't done that with the slightest mod. lol :)
 
Well Id look to Double D, Steely Dan, and Brenndatomu for solid highly experienced advise. Most everything I've learned about wood stoves period and Tundras dribbled down from those guys on here. I would say one 8" output would restrict the air flow too much(cfm's) and not allow the tundra to properly strip heat from the plenum. U would likely get hot air longer but I don't think you would get as good of volume of hot air and risk over heating the plenum. The biggest problem I see with this though is lose of volume of heated air. I would guess twice the amount of hot air is worth more than half the amount of slightly hotter air slightly longer. I do not think the increase in temp and time of delivering hot air would be enough to over power the advantage of the volume and removal of air from the plenum the two 8" outputs would provide. And it will certainly void the warranty.. not that most of us on here haven't done that with the slightest mod. lol :)


Sorry, I worded it poorly. I am going to be using both 8 inch pipes. However, one is only going to be about a meter long, while the other, which will supply further down the main trunk of the plenum, will be around 4 meters long. I am mostly just concerned about losing too much heat on the longer run and having a temp imbalance throughout the home.
 
Sorry, I worded it poorly. I am going to be using both 8 inch pipes. However, one is only going to be about a meter long, while the other, which will supply further down the main trunk of the plenum, will be around 4 meters long. I am mostly just concerned about losing too much heat on the longer run and having a temp imbalance throughout the home.

Are both runs tapping into the same plenum? If so why tap 1 in further away? What are you actually trying to accomplish/avoid by doing this?
 
Are both runs tapping into the same plenum? If so why tap 1 in further away? What are you actually trying to accomplish/avoid by doing this?

Yes, they will both be going to the same plenum. Basically I am trying to heat the upstairs as much as I can, and the main line that runs through the wall to the upstairs bedrooms is at the far end of the plenum. And also, the location down on that end has less of a conjunction of AC line sets and hot water piping making it easier to get into and run the ductwork.
 
Sorry, I worded it poorly. I am going to be using both 8 inch pipes. However, one is only going to be about a meter long, while the other, which will supply further down the main trunk of the plenum, will be around 4 meters long. I am mostly just concerned about losing too much heat on the longer run and having a temp imbalance throughout the home.
Well i have a manual damper in one of the 8" outputs. It helps me zone my temps as one output goes to back of house an other to front. I have isolated duct work installed separate from the gas furnance ducting.
 
I am trying to heat the upstairs as much as I can

Another option is to partially close the downstairs dampers. I'm not the duct pro, but since the Tundra only has two 8" outlets, and they dump into the plenum (at roughly the same static pressure), that the difference between 1 meter and 4 meter could give fairly unbalanced flow between the two outlets. I don't know if it's a huge deal, but my outlets are 12 inches long before dumping into the same plenum, and I still have different temperatures on the outlets, I don't know why. My assumption is that uneven temperatures in the outlets are probably ok, but suggests to me that there is less airflow on one side than the other, which suggests that some heat is going up the chimney that wasn't transferred to my house.
 
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I would install them close together and damper down the 1st floor. But running a separate line should not hurt.
 
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Our Caddy doesn't have a controller on it, and after 8, 10, 12 hours depending on the weather the house is within a degree or two when we wake where the thermostat is set. It was 32 last night, and after a 12 hour burn, the thermostat was set at 73 and the house was 72 with enough coals to still cycle the blower. When it's much colder in the single digits, the thermostat still keeps the house within a degreeor two after 8 hours. The days of wild temperature swings dissapeared when we upgraded.

I am running a Caddy in the basement of our new home. Love it, it works great and I get good house temperature control, especially as I learn how to fire the furnace.
One thing I struggled with is the open or closed operation of the thermostat controlled damper. I never felt like i could get it set so that it worked for every condition. So I modified it a bit. I added a turnbuckle in place of the chain that pulls the damper open. Now I can control how far the damper opens when the thermostat calls for heat. More open when it is colder outside, house is cold or when I am kindling a new fire, etc. Less open when I want to hold the fire longer, warmer weather, etc. Great addition to otherwise completely stock setup.