Everything Drolet Tundra - Heatmax...

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2nd fire of the year. I figured I get the stove pipe up to 625 f before shutting the damper. Problem is I could only get it up to around 500 f. It was a small load. Maybe this is why?I did get good ssecondary burn for about 10 min. tricky tricky
Interesting findings here, I fired the Tundra tonight for the first time since putting my "restrictor plate" on the intake holes...wow, what a difference! It is in the mid 30s here right now, so this is probably the coldest temp I have fired up at since I have installed this thing.
Even with the cooler temps it seems to take a lil longer to get up to my programmed high limit temp (500* right now) and it seemed to be almost stalled out at 500, it would have ripped right past that temp to bounce off the 625* ceiling before. And the firebox is not nearly the turbulent, raging inferno that it was before when the damper was open, so I'd say mission accomplished for me since I was trying to soften the "drop the hammer" effect of the damper opening.
I also noticed that my draft reading stays higher when the damper is open now, which makes sense if you think bout it. The draft would go from -.06", down to -.04" with the damper open, (at first) now it only drops to -.05"

We'll see how this all pans out long term...so far I am liking the mods I have done. The "light it and walk away" capability that comes with the temp controller is pretty cool IMO ("two thumbs up" smiley inserted here)(if hearth had one) ::-)
 
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Interesting findings here, I fired the Tundra tonight for the first time since putting my "restrictor plate" on the intake holes...wow, what a difference! It is in the mid 30s here right now, so this is probably the coldest temp I have fired up at since I have installed this thing.
Even with the cooler temps it seems to take a lil longer to get up to my programmed high limit temp (500* right now) and it seemed to be almost stalled out at 500, it would have ripped right past that temp to bounce off the 625* ceiling before. And the firebox is not nearly the turbulent, raging inferno that it was before when the damper was open, so I'd say mission accomplished for me since I was trying to soften the "drop the hammer" effect of the damper opening.
I also noticed that my draft reading stays higher when the damper is open now, which makes sense if you think bout it. The draft would go from -.06", down to -.04" with the damper open, now it only drops to -.05"

We'll see how this all pans out long term...so far I am liking the mods I have done. The "light it and walk away" capability that comes with the temp controller is pretty cool IMO ("two thumbs up" smiley inserted here)(if hearth had one) ::-)


The only times I've not hit the 625F limit is on smaller loads. I initially checked draft when I first installed the furnace and recall the draft would go high when the damper was open and temps climbed but was with in spec with the damper closed and good secondary action. Don't have a barometric damper and not sure I need one with the control and the fact that once the damper is closed and the furnace has good secondary action my flue temps are in the 290-350F range. Pretty efficient compared to my 30NC which will have 550-650F flue temps during active secondary burn.

I'm loving the "light and walk away" feature as well ;-)
 
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FIred my Tundra up for the first time last night. Is it sad I was as excited as a kid on Christmas? Been saving and buying (furnace, liner, manometer, stove pipe, etc) as I can. Right now I'm just letting the ducts dump into the basement. I'm not tying into existing ductwork, as it is duct board and flex duct. I'm going to keep Tundra and propane as two completely separate systems. I was wondering for those of you that don't tie into existing ductwork, how many registers you have and what sizes. Total feet of 8" duct and branches (6"?).
 
Is it sad I was as excited as a kid on Christmas?

Heck no! That's how it should be. :)

how many registers you have and what sizes.

I've actually had 2 ductwork configurations. The simplest to describe was my two 8" outlets were each 2 ft long before dumping into a metal box so they could be at equal pressure. From that box I had three 8" runs that each connected to a 6x12 floor register. The runs were 6 ft, 6 ft, and 18 ft. That worked just fine and delivered plenty of airflow and heat.

My current configuration has the two 8" outlets each about 1 ft long until they dump into a plenum, then I have three 8" runs to the same floor registers, the runs are about 6 ft, 1 ft, and 9 ft. I can't even get up to 0.20 static pressure on the fastest blower speed because there's such little resistance in the system. And, I don't get much air flow out of the 9 ft run, and could just close it if I wanted to.

So, if you are going for simple and your house allows short runs with only 1 or two elbows, you could probably get by with just running each furnace outlet through 8" duct to its own floor register. But you might have to be lucky for that to work, with a floorplan that evenly splits the heat load between the two registers, with short straight runs, and with ample return air.
 
I was wondering for those of you that don't tie into existing ductwork, how many registers you have and what sizes
When I installed my sisters Tundra I put a plenum over the two duct take offs. The plenum has (1) 7" 90* elbow that dumps right out to the basement. (1) 3-4' run of 7" pipe to the room next door, (2) 20' runs of 7" going to two 14" x 6" (or 8", can't remember) registers upstairs. Each one of the 4 runs has its own damper too.
Mine just connects directly to my main ductwork, which is conveniently right above it, via the two 8" pipes.
 
For you guys that have had your Tundras for a while, how often do you have to clean your heat exchangers? Do you see any noticeable difference in heat output?
 
On my Caddy I generally clean my heat exchangers at the end of the heating season and a couple times during the heating season. Dry wood definitely helps with creosote build up in the heat exchanger.

The chimney gets cleaned at the end of the season and once during the heating season on a mild day in late January.
 
I'm thinking about trying to work a small (4"?) chimney brush into the tubes to give them a thorough cleaning. The factory tool knocks the high spots off, but I'd like to see more bare metal.
What got me started on this is the duct air temps off this thing, compared to my Yukon. The Yook blower shuts off at 120*, the Tundra will only hold duct temps over 120* for 30 seconds once the blower kicks on. But I guess I'm comparing military grade weaponry to Playschool here...
 
I typically clean them once a month. I never really see any noticeable difference in temp, and I'm always measuring duct outlet. My unit is serial number 1406 so it is a newer one with the smaller damper inlets. This year I sealed up the baro and went with a cast iron damper. So far it really seems to have evened out my draft, under full burn it is will hover between -0.06 to -0.075(it's on the high end I know but it has never hit -0.08). With the thermostat calling for heat my ducts will hold 120 deg no problem (highest I have recorded was with sycamore and it was 132). My blower is set on number 3 and I have the adjustable snap disc set to 105 on. I do not have my cold air return connected yet, I ran all last winter with out it. I was wondering if I was the only one who thought the brick kit fit terrible, I can see I'm not the only one.
 
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I was wondering if I was the only one who thought the brick kit fit terrible, I can see I'm not the only one.

I installed two of the kits- both the bricks that lay flat on the bottom of the firebox at the front needed a slight notch in the angled cuts to fit- not perfect fit but I'm happy to have them no charge from SBI. I think 30 seconds each with the angled grinder took care of the issue. I also fabricated some 12 gauge stainless angles to protect the soft vertical firebricks from damage when loading wood. The soft bricks dent easily but they also are much better insulators than the hard bricks.
 
Does anyone know of a distributor of the drolet furnaces thats local to southern ontario?
 
Thanks for the mini review KARB! :)
This year I sealed up the baro and went with a cast iron damper. So far it really seems to have evened out my draft, under full burn it is will hover between -0.06 to -0.075(it's on the high end I know but it has never hit -0.08)
Is that with the damper fully closed?
With the thermostat calling for heat my ducts will hold 120 deg no problem (highest I have recorded was with sycamore and it was 132). My blower is set on number 3 and I have the adjustable snap disc set to 105 on
No kiddin?! Man, Ima hafta do some more checking and tweaking. How long does it take for the duct temp to get to 120 after the tstat calls for heat? And how/where are you measuring that?
Blower on speed 3 huh? Have you ever checked your SP?
 
FIred my Tundra up for the first time last night. Is it sad I was as excited as a kid on Christmas? Been saving and buying (furnace, liner, manometer, stove pipe, etc) as I can. Right now I'm just letting the ducts dump into the basement. I'm not tying into existing ductwork, as it is duct board and flex duct. I'm going to keep Tundra and propane as two completely separate systems. I was wondering for those of you that don't tie into existing ductwork, how many registers you have and what sizes. Total feet of 8" duct and branches (6"?).
I have a total of 7 Registers,
1- 7" run into a 4x14 register - large living rm
1- 6" run into a 4x12 register - large dining/kitchen
5- 5" runs into 4x12 registers - bedrooms/mudroom/another into kitchen/dining
1st 8" supply has about 20' of 8" pipe with 1- 7" and 2 - 5" branches coming off of it.
2nd 8" supply has about 40' of 8" pipe with 1- 6" branch and 3- 5" branches coming off of it.
I have a ranch so i needed a good amount of ductwork to get the heat to where i needed it.
If you look at my earlier post i believe i posted a picture of my ductwork layout.
When i figured my ductwork i did it using a static pressure of .2wc that SBI calls for.
I have a 12" return that is about 15' long.
When planning your runs here is the info for .2 WC static pressure
8" = 330 cfm
7" = 225 cfm
6" = 160 cfm
5" = 95 cfm
4" = 52 cfm
You have 2-8" supplies coming off your furnace each giving 330 cfm for a total of 660 cfm
Now you need to figure out your duct sizing so you can get rid of that 660 cfm.
What i did is take the total sq ft i was going to heat and divide it by the total cfm.
So 660cfm / 2000sq.ft = .33 cfm per sq.ft.
so a 12x12 room has 144 sq ft take .33x144=47.52 cfm
A 4" run would work for that room but i would not do any 4" runs make 5" your minimum you can always damper it down.
This is not a rocket science approach to figuring out your heat load just what i used and the house is nice and even with the heat distribution.
One word of advice with the left side duct seeming like the warmer of the two ducts use that one for your longest run.
Again i did not do a real heat load calculation as one would with a heating system. I was keeping it simple and basic which has worked out really well. Sorry for the long winded post but just trying to explain it the best i can on how i did it.

By the way the house is 2800sqft total i am just supplying heat ducts to about 2000 sq ft of it and the other 800 sqft seem just fine, I did not do runs to bathrooms/walk in closet/pantry that kind of stuff.
 
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Thanks builder, sounds very similar to what I am working on. All I can say so far is I sure can get the basement a lot warmer than the upstairs. I appreciate your explanation.
 
Home Hardware sells the Tundra. Might have to order it, but any HH should be able to do that for you.

If that helps.
I saw that on the list on the drolet site. Wasn't crazy about the canadian pice compared to American ... Go figure made here and cheaper there. Was thinking to wait for our dollar to bounce back again and trip down to Pick one up. I'll inquire next time I'm in town if they can order and how much. Definitely looking to replace the old hotblast
 
Buying anything south of the border, from north of the border, just all around stinks.

By the time you get it here & fully in your possession, you can likely budget 2x the original product price - exchange, customs/duty, and shipping.
 
Buying anything south of the border, from north of the border, just all around stinks.

By the time you get it here & fully in your possession, you can likely budget 2x the original product price - exchange, customs/duty, and shipping.
Ya and like I said it's made in Canada but sold for cheaper in the USA. Oh well I guess
 
Ya and like I said it's made in Canada but sold for cheaper in the USA. Oh well I guess

Isn't that just the exchange rate working against you. As in, your Canadian dollars are worth less than our American dollars? If so, you should be more easily able to scrape up more of them.