Everything Drolet Tundra - Heatmax...

brenndatomu said:

Damper stuck open after I re-loaded after work...yeah...154* duct temp!

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Now that sounds more like it! How long did it take you to reach 154? I can get that after about 20 minutes open on the damper, right about the time the wood is charred enough to sustain secondaries.

DoubleB said:

Is that for the Tundra only, or did you notice for all Drolet models? Either way, a weaker warranty is not the way to fix problems or improve your reputation and sales. I suppose in my case, my largest crack at the bottom of the loading door also pulled the weld off of the door flange, so maybe I still would have been covered, but not for much.

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I only looked at the Tundra model I was looking for info on the Tundra ll but didn't even see it listed on the site.

Also looking at the heatpro model it had me laughing. Looks like all they did was copy and paste from the tundra manual with some add ons. When you look at the burn time table it has the max load at 3.0 cuft which is the same as the Tundra. Good thing SBI double checks things, not like the owners manual is all that important.

brenndatomu said:

If y'all are running yours that hard normally...maybe SBI has a point ^ ^ ^ ?

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I guess I don't think 154F is all that hard when the furnace is getting up to temp. If it takes me 20 minutes to reach 154F, then that load took 17 minutes to get to the point where the secondaries could sustain. The next load may be a colder start that needs 20-30 minutes to get temps for sustaining secondaries. And the next load with lots of coals only needs 10 minutes. As a new load gets going, my firebox temp and wood temp/char lag behind the hot air temps, and there really is not much time difference between rapidly rising air temps, and a firebox that's trying to catch up enough in temperature. That's just the way my furnace seems to behave.

So if SBI expects users to know the exact minute between 10-30 that the damper must close to avoid "stretching the capacity of those heaters", then I don't think they did their job. Especially when the manual suggests relying on a thermostat to open the damper for more heat without any regard for register temps or user oversight.

Has anyone ever considered a horizontal damper that would cover some or all of the 3 square holes behind the front damper door? It seems like this could fine tune the damper rather than just full open or full close.
I'm picturing a horizontal sliding plate with holes that would line up with existing holes.

Maybe it's just the whisky talking....

brenndatomu said:

Just so we are on the same page, this was with the blower running...

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Yep, same page.

brenndatomu said:

I know that on stoves it is pretty universally accepted that 700*(ish) stove top temp is considered toward the top end of the temp range where they should be run normally.

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I still train my IR thermometer on different parts of the front face of the Tundra sometimes. Hottest parts I've found is the top corners of the loading door. I used to easily get >600F with the damper wide open while getting up to temp. And then, I'd get 750F or hotter with the secondaries cruising. Now, with my non-insulating firebrick mod, the 750F went down to about 600-650.

brenndatomu said:

just a "on/off" switch...hope nobody ever forgets to shut that off!

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No kidding! I have once or twice. Another reason I'm glad to have added overtemp protection. In fact, just this morning before I left for work I loaded a full load, set timer to 20 minutes, put on my coat, and went to the basement to double-check that I could leave. Sure enough I had forgotten to turn off the damper switch from having burned down coals...

brenndatomu said:

I kinda tuned mine with aluminum high temp tape over the holes...I went too far, ended up going back to the same size holes that they put on them now...or the resrictor kit that they have...

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That would work in a perfect world but it seems like nothing is consistent with this furnace. Wood type, moisture content, outside air temp, draft, wind speed all have an effect on how my furnace acts. I think I have a female model?

brenndatomu said:

Boy, that would be sweet. I looked around a little bit and didn't find anything that seemed to be quite what you describe. Have a link or a suggestion as to where to look?

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I looked at a unit called Fan Handler before I put my speed controller together. It's a VFD. I didn't spend to much time checking it out but it may work. Kind of pricey if I recall plus I don't really like the idea of having a VFD running in my house.

What is the concern with a VFD in the house?

Smoke Signals said:

I don't really like the idea of having a VFD running in my house.

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Why? VFD's are awesome, But very pricey.

Maple beat me to it...

maple1 said:

What is the concern with a VFD in the house?

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I just don't like the idea of all that dirty power, interference and noise.

That was 10 years ago.

brenndatomu said:

We have VFDs all over at work..tons of instrumentation and sensors...no interference or "dirty power" issues

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I recently had to change a couple of old ones out at work because of interference and I will have to admit that the new ones do seem to be better.

I want to thank all who have contributed to the information on how to build the damper controller. I put one together the other day and have to say it really adds to the controlability of the Tundra.

Alright gentlemen here is my go with a plenum. I just lasered it out of 0.029 304L (I had a few pieces laying around) I will try to get around to installing it within the next few days. The reason for the front being angled is because my cold air return is above my Tundra. I could have made it straight up but I figured with it being angled it would help with air flow. For the fan snap disc and high limit just for now I'm going to have them inside the plenum in the same location, I will just make a simple bracket for them to mount to and to have the wires protected from direct heat.

KARB2014 said:

Alright gentlemen here is my go with a plenum. I just lasered it out of 0.029 304L (I had a few pieces laying around) I will try to get around to installing it within the next few days. The reason for the front being angled is because my cold air return is above my Tundra. I could have made it straight up but I figured with it being angled it would help with air flow. For the fan snap disc and high limit just for now I'm going to have them inside the plenum in the same location, I will just make a simple bracket for them to mount to and to have the wires protected from direct heat.

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I like it, did you draw that up in Solidworks?

3fordasho said:

I like it, did you draw that up in Solidworks?

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Thank You. Yes Sir solidworks.

KARB2014 said:

Thank You. Yes Sir solidworks.

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I thought that title block looked familiar ;-) How much of the factory sheet metal are you going to open up on the top?
My thought would be open up mostly towards the front directly above the crossover that connects the smaller side HE tubes to the large center tube or maybe everything under the plenum?

I plan on removing the entire factory top. If this doesn't work I want to be able to easily go back. I'm going to use the factory screw holes to attach the new plenum. I'm curious as to if this causes me to get more build up in the heat exchangers. I have a pretty good feel for how they look after a month so I will be keeping an eye on them. I will more than likely try this with out the turb being in there first. I'm shooting for this all happening today after work as I'm letting it burn out today because I want to run the sooteater up the chimney today(I'm a month late because of the warm start to the season).