Everything Drolet Tundra - Heatmax...

[Builderml]

So all this time I have been burning it according to what sbi suggest in the owners manual. Fill firebox with desired load of wood and let it go thru its whole cycle. Once you burn that down and you notice its cooling off reload again. Repeat and repeat. A few days ago I loaded when I woke up filled firebox. about 45 mins later (peak burn) came back down before heading to work and figured heck I can squeeze a couple more pieces now that everything has settled down in firebox. So I put a couple pieces on top and closed door. I never opened damper. My secondary burn almost doubled. Increased my stack temp about 15*- 20*. I have tried this now for the past few days with the same results. I know the tundra likes to run in secondary mode which it was designed for. I figure if I can get more heat out of it this way why not. Wondering if anyone else has tried running it this way with this same results? I know adding the fresh wood while in peak burn (almost melts my hands trying to load at this point ) causes more smoke for the secondaries to burn off. Anyone else been burning it this way?

 

[brenndatomu]

I've done it before. It's kinda the same thing as loading on a huge pile of screamin hot coals, it gets the wood outgassing fast and hard, LOTS of fuel for the fire. For me anyways, the only issue with loading this way is that I get a little smoke out the door sometimes.
When the stove guys do this, it's called "going nuclear"...

 

[brenndatomu]

Just something interesting...I said before that the front of my Tundra seems to be where the heat is at...so I'm playing with my Christmas present tonight (thermal imaging camera) giving the house a scan when I walk by the Tundra. Visual proof of my previous statement, noticeably hotter toward the front. No wonder the front (3rd) duct runs ~10* hotter

 

[maple1]

You just now got to pointing that thing at your furnace?

I think I would have made a bee-line for it as soon as I got it out of the box.

(Interesting stuff....)

 

[KARB2014]

I made some turbs out of 0.032 304 stainless. They are similar to the ones that @DoubleB designed. I have nothing scientific to go off of but since Friday I have noticed that in the coal stage I seem to be getting more heat. The reason I say this is because I'm able to keep the house above 70 long enough to burn down the coals with no intervention of me. The blower also doesn't cycle as much. Under a fresh load while under full flames my Chimney pipe doesn't go over 350, Before it would get really close to 400. Now those number are with a full load and damper being open for over 20mins. I still have my secondary intake about 50% closed off.

 

[KARB2014]

Just something interesting...I said before that the front of my Tundra seems to be where the heat is at...so I'm playing with my Christmas present tonight (thermal imaging camera) giving the house a scan when I walk by the Tundra. Visual proof of my previous statement, noticeably hotter toward the front. No wonder the front (3rd) duct runs ~10* hotter

Looking at that I'm really thinking it would benefit us all to really make a plenum for our furnaces. I knew the front ran hotter but this shows how much of an air dam that is in the front. It also have me wanting to look into how much time I would have into making a false front.

 

[sloeffle]

So all this time I have been burning it according to what sbi suggest in the owners manual. Fill firebox with desired load of wood and let it go thru its whole cycle. Once you burn that down and you notice its cooling off reload again. Repeat and repeat.......... Wondering if anyone else has tried running it this way with this same results? I know adding the fresh wood while in peak burn causes more smoke for the secondaries to burn off. Anyone else been burning it this way?

The manual for the older Caddy's mentions nothing about how to burn the furnace. It would of been nice to know a few years ago. Depending on the weather and house temp I will sometimes reload in the middle of a peak burn. I will just throw a couple splits in and prop the damper door open to about and 1/8th" for about 5 minutes and it will normally go back to burning the way it was before.

almost melts my hands trying to load at this point )

Bought some of these welders gloves off of Amazon to help the heat on my hands.

 

[DoubleB]

I have noticed that in the coal stage I seem to be getting more heat.

Under a fresh load while under full flames my Chimney pipe doesn't go over 350, Before it would get really close to 400.

Nice to hear your results. In fact, I believe I have noticed the same things on mine. My register temps are higher, and my chimney pipe (single-wall black pipe) temps are down about 50F from before.

Now, my caveat is that I cleaned the HX tubes 24 hrs before I put in the turb, and they were also more dirty than I expected. So of course that improved performance too, and I don't know how much of that is due to the turb vs. cleaner tubes.

Another difference I noticed (might be imaginary, but who knows), is it seems smoke spills out a bit easier during reloads. If true, then maybe the turb is causing some resistance in the main HX tube so I upped my baro to a 0.06" draft to compensate. Who knows if that has things burning a bit hotter or not (but my burn times are no worse).

Weather here has been quite cold (-12F at night and breezy), spotty sun during the day, 2100 sq ft old farmhouse, and the Tundra is just keeping up. Performance is no worse with the turb installed, and might be better, so it stays for now.

 

[Builderml]

Looks like I need to keep an eye on the two corners below the H.E door. Almost 1/8" long on the right side and maybe 1/16" long on the left side. I'm afraid to say the word but it starts with a "C". Still trying to figure out if its the paint or the steel. Now you know I'll keep you posted as things progress.

 

[Builderml]

Is the area around the H.E. door part of the firebox at that point? I don't think so because none of that area is even welded. To me if it was part of the firebox it would allow some smoke to come out.

 

[Builderml]

I wish it wasn't such a pain to load pictures on here from my phone. Can someone on this site fix that please???

 

[KARB2014]

Is the area around the H.E. door part of the firebox at that point? I don't think so because none of that area is even welded. To me if it was part of the firebox it would allow some smoke to come out.

Mine is not welded around the heat exchanger door as well. I was wondering if that was something they were doing on the higher serial numbered units.

 

[Builderml]

Mine is not welded around the heat exchanger door as well. I was wondering if that was something they were doing on the higher serial numbered units.

All I have are some tack welds along the bottom.

 

[Builderml]

Can you see what i see? After scratching it this morning with a nail its safe to say that it is not the paint. Right side of H.E. opening. I think its safe to say that i have the newest model out of everyone on this site. " #1993 " I believe everyone on here gave SBI the benefit thinking things were finally figured out and cracking problem solved. Well here's your answer.

 

[brenndatomu]

Yup, I's 'fraid of that.
I weren't gonna say anything yet, but at y'alls recommendation that these things don't heat well unless you run 'em hard...I been running the bag off of mine during this cold snap and I see that one of the existing "C"s has grown, despite the heat shield. I will drill it tomorrow, see if that stops it without welding...sorry to see that builder...gotta say though, I'm not too surprised with the temps you have been getting outta 'er...

 

[DoubleB]

Uh oh Houston. Crack indeed. Sorry to see that. I agree that bumping it off the high limit probably didn't help things, but that's still not good to see. I think the HX flange you asked about is welded on the inside, not outside, but would have to open the door to confirm.

I checked my cracks a couple days ago I don't think they have grown this year, but neither did I mark them this summer as @brenndatomu wisely did. My temps on the front face of the firebox have definitely been lower since adding overtemp protection and the firebrick. That said, I actually get my highest temps on the front face during secondary cruising, at the top corners of the loading door. Seems those temps actually drop a bit if I open the damper (even though everything else skyrockets).

 

[KARB2014]

I would really like to know if any of the Caddy owners have looked behind the false fronts. I'm just curios if any of them have cracking and just can't easily see it.

 

[TheBigIron]

I know that it was mentioned in earlier posts about building a false front for the furnace. What would that entail? Anyone know? Thanks in advance.

Dave

 

[laynes69]

I've been behind mine and there was no cracking. Like mentioned before, the front remains cooler, and there's room for expansion on the heat exchanger and the firebox. That solid front probably doesn't move, but the firebox and exchanger will heat and expand.

 

[Builderml]

I called SBI to see what i needed to do at this point. Email has been sent along with pictures. Now its a waiting game to see what they say and how they respond. I just hope it doesn't have to get nasty.
FYI
I know many may think that the Caddy and Tundra may have the same firebox. I asked the tech while i was on the phone if they were both pretty much the same thing. Response was no not even close.

 

[sloeffle]

I would really like to know if any of the Caddy owners have looked behind the false fronts. I'm just curios if any of them have cracking and just can't easily see it.

Taking the false front off looks like it will be a lot of work. I think I am going to pass, sorry. I have had my furnace for three or four years and I haven't seen any cracking.

Where is the cracking taking place on the Tundra's ?

 

[DoubleB]

Good luck Buildermi. I hope it turns out well. Keep us posted.

I know many may think that the Caddy and Tundra may have the same firebox. I asked the tech while i was on the phone if they were both pretty much the same thing. Response was no not even close.

I believe they have a tech that would tell you that. On another forum one of the original Tundra/Heatmax reps from SBI described how they're basically the same firebox. (Not to mention those on this forum who have seen both). From what I experienced and have read here, it's hard to get a straight story out of SBI.

 

[brenndatomu]

I know many may think that the Caddy and Tundra may have the same firebox. I asked the tech while i was on the phone if they were both pretty much the same thing. Response was no not even close.

I beg to differ. We have already proven that the SBI reps don't know what they are talking about half the time.
The more time I spend working on this thing, and now that I have had my head inside (and all around) a Caddy...I think it is just as Fyrebug said, identical fireboxes. The only difference as far as the firebox is concerned, is that the Caddy has an air jacket around the front so the blower air can pass between the jacket and the front firebox wall. Well, that and the ash drawer plug instead of a ash grate like Caddy.
The only place that I can't say if they are the same or not is the grade of the metal itself...but I really suspect it is the same.
Oh, and the loading doors are hinged on opposite sides...

 

[Builderml]

Yup, I's 'fraid of that.
I weren't gonna say anything yet, but at y'alls recommendation that these things don't heat well unless you run 'em hard...I been running the bag off of mine during this cold snap and I see that one of the existing "C"s has grown, despite the heat shield. I will drill it tomorrow, see if that stops it without welding...sorry to see that builder...gotta say though, I'm not too surprised with the temps you have been getting outta 'er...

I never said that.

 

[DoubleB]

The only difference as far as the firebox is concerned, is that the Caddy has an air jacket around the front so the blower air can pass between the jacket and the front firebox wall.

We've talked about the Caddy's front air jacket for a year around here, and it only now occurred to me to just blow a fan over the front of my Tundra and see how much that drops the steel temps. If the temp drops a lot, that might suggest the front air jacket on the Caddy is indeed key to preventing cracking.

Not sure what to do after that, but at least might strengthen one of our theories and we can figure how to deal with it after that.