Everything Drolet Tundra - Heatmax...

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Voltage hovers around 120-121V.

Nonetheless, if someone has only 110V but draws the same amount of power, they're still pushing about the same amount of air.

115-125F at the top of the plenum, where the blower snap disc is located. Registers are, of course, a bit less.
 
Static pressure is more for the ability to push the air out of all registers as needed. That's why you don't take a run off your main at the end of the main, you need a static leg. static pressure is a lot like tires, 285/65/16 these are not height and width but a formula combination. Sp is important, but so is CFM. You could be moving1600 cfm at .3 sp or 1600 cfm at .2 sp the difference is velocity. So in short, the ductwork needs to be big enough to carry the cfm's but small enough for the correct sp. I oversized my ductwork for gravity heat in power outage or fan failure, then dampered each takeoff for heat need in each rm. The longest take off to the 2nd fl had to have the damper removed and still is a little low unless I am on high fan. But then I am removing more heat from my unit than I want. (more cfm) If air moves to fast past the HE it can pic up the heat, if to much air passes through it pics up to much heat but is not hot. Does this make sense to you?
 
Alrighty...changed the air filter...RSP -.15", down from -.30".
Rechecked the SSPs...
Both side ducts at .17 to .18"
Front duct at .10" (on purpose...it runs the hottest by far)
Running watts at ~210.
I can easily run the SPs up higher, but then as stihlydan said, not enough air flow to distribute well. This seems to be a good balance so far. Blower runs quite a while after loading, doesn't start cycling on/off too early, duct temps aren't too low (not as high as I'd like though)
Coldest day/night here since I have had this machine, so far I have been a little surprised...she's keeping the tstat more or less satisfied...doesn't seem like there is much in the "reserves" though, but I am already a little surprised, sooo...we will see
 
Alrighty...changed the air filter...RSP -.15", down from -.30".
Rechecked the SSPs...
Both side ducts at .17 to .18"
Front duct at .10" (on purpose...it runs the hottest by far)
Running watts at ~210.
I can easily run the SPs up higher, but then as stihlydan said, not enough air flow to distribute well. This seems to be a good balance so far. Blower runs quite a while after loading, doesn't start cycling on/off too early, duct temps aren't too low (not as high as I'd like though)
Coldest day/night here since I have had this machine, so far I have been a little surprised...she's keeping the tstat more or less satisfied...doesn't seem like there is much in the "reserves" though, but I am already a little surprised, sooo...we will see
What are you getting with the tip pointed down into the air flow? While this may not be an accurate way of checking the actual s.p. we should be able to compare. I was at about .25 - .27. If I had to guess I think my s.p. is much lower compared to yours.
 
With this being the coldest morning by far (5* actual and -5 wind chill) looks like the Tundra can hold the house temp. I don't see myself being able to raise the temp much if at all. I just reloaded now with a full firebox and settled into cruise mode so I'll be watching over the next hour as to what she is able to do. I must say I am very pleased with this.
 
Here's a few more temps I haven't listed b4, center of H.E. tube door is 327*, my single wall stack pipe 196* 2' up from my tee. measurements taken holding infered gun about 6" in front of surface. I never noticed before but the distance the gun is held away from the object impact's the reading a good amount. I am also about 30mins into cruise mode.
 
Yeah, I gotta say, my thermo is saying 8* right now, weather guessers were saying a low of 10* and wind chill ~0 and the tstat says 71* in the house (I have it set for 72*. I loaded 'er up with Hickory n Oak last night at 11, so I am surprised, but she kinda did OK, at least for what I was expecting anyways. The damper was open and there was some screamin hot coals at the back still, I raked 'em forward and about melted my face off! Another load of Hickory and oak at 6:10 AM, so we will see how she does on a 10 hour load today. Supposed to be a high in the mid 20s...
I'm sure if not for the recent changes, things would not have been so rosy this morning...I'll detail the changes made here later today
 
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measurements taken holding infered gun about 6" in front of surface. I never noticed before but the distance the gun is held away from the object impact's the reading a good amount
They usually say on the gun what distance they are optimized for...6" is pretty common. They like flat or satin black surfaces the best too...
 
Yeah, I gotta say, my thermo is saying 8* right now, weather guessers were saying a low of 10* and wind chill ~0 and the tstat says 71* in the house (I have it set for 72*. I loaded 'er up with Hickory n Oak last night at 11, so I am surprised, but she kinda did OK, at least from what I was expecting anyways. The damper was open and there was so screamin hot coals at the back still, I raked 'em forward and about melted my face off! Another load of Hickory and oak at 6:10 AM, so we will see how she does on a 10 hour load today. Supposed to be a high in the mid 20s...
I'm sure if not for the recent changes, things would not have been so rosy this morning...I'll detail the changes made here later today
Brenn sounds to me like you may be doing a half hearted happy dance.;lol
 
Its later!!! Where are the flippen details???
Platience young glasshawper, platience. :p Jr. needed his baba...
Another load of Hickory and oak at 6:10 AM, so we will see how she does on a 10 hour load today. Supposed to be a high in the mid 20s...
Well, when I got home from work tstat said 71*, this was at 4:30, so almost 10.5 hrs, high of 25* out today. Not too bad I guess, still had good coals for an easy relight. Threw in some more Hickory and Oak...it took a while, but it is back up to 72* in here as of about 8:30-9:00. I really don't like that I can only raise the house temp 1, maybe 2* during the hottest part of the burn, seems like it should do more...
The recent changes were: adding the third duct, and then running it almost wide open
A new air filter (which lowered RSP)
And last but far from least, I lowered the temp controller to close the damper at 350* and reopen at 250*, which has been working out really well. 350 is plenty of temp to fire off the secondarys and the temp will usually hold around 300 for a couple hours. A couple hours more before flue temp drops to the point where the controller will let the tstat re-open the damper. So we are 4 hours in now. 2 or 3 hours more of heating with the tstat cycling the damper open/close (so the high point of the heating curve is past) So we are 6 or 7 hours in now and it is likely that the damper is just staying open all the time now, which gives ok heat (not great) from burning down the coals.
At this point I think I am pushing this thing about as hard as I can without just running damper open all the time...unless adding a plenum ends up making a big difference, I dunno...
Before somebody suggests that I am not running it hot enough...even when I had the temp controller set to shut down at 550*, once the damper closes the temp always wants to settle back down to that 3-350 range anyways, and fairly quickly, so...
This is even with -.07" draft last night, so not low draft, and my wood is SUPER dry 3 year CSS Oak and Hickory, so not wet wood...
Also (gettin past my bedtime here...) I installed a turbulator in the center HE tube. If you want to know what that is, search that term in the boiler room, there has been lots of talk about them. Basically it causes the flue gasses to be turbulent and have to contact the walls of the HE tube instead of the majority of the flue gas volume just blasting down the center of the tube without much contact time with the tube walls. It did seem to drop my flue temps some...
I'll get pics of this thing the next time I open the cleanout door. Nothing fancy...quicky homemade deal...some good ole redneck injoonearin...:p
 
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Brenn sounds to me like you may be doing a half hearted happy dance.;lol
Yeah, I suppose you could say that...a weak woo hoo and then movin on
 
Platience young glasshawper, platience. :p Jr. needed his baba...
I installed a turbulator in the center HE tube. If you want to know what that is, search that term in the boiler room, there has been lots of talk about them. Basically it causes the flue gasses to be turbulent and have to contact the walls of the HE tube instead of the majority of the flue gas volume just blasting down the center of the tube without much contact time with the tube walls. It did seem to drop my flue temps some...
I'll get pics of this thing the next time I open the cleanout door. Nothing fancy...quicky homemade deal...some good ole redneck injoonearin...:p
This thread had me wondering if the Caddy or Tundra could benefit from having turbulators installed. Unfortunately I have all of the wrong tools ( I am a woodworking guy ) to fabricate something. I will be interested to see some of your redneck engineering.

Scott
 
This thread had me wondering if the Caddy or Tundra could benefit from having turbulators installed. Unfortunately I have all of the wrong tools ( I am a woodworking guy ) to fabricate something. I will be interested to see some of your redneck engineering.

Scott
I've read of some guys using logs chains. Do you have old or broken chain you could put in the HX as a test?
 
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I think the chains are for vertical tubes, whereas these are horizontal. Maybe?

It is kind of odd, now that the thought is here, that I haven't seen turbs used before in a furnace. Seems if they are effective in boiler HX tubes in certain situations, they could be effective in furnace HX tubes. Huh...
 
Do you have old or broken chain you could put in the HX as a test?
I think the chains are for vertical tubes, whereas these are horizontal
Exactly
It is kind of odd, now that the thought is here, that I haven't seen turbs used before in a furnace. Seems if they are effective in boiler HX tubes in certain situations, they could be effective in furnace HX tubes. Huh...
Yeah, I had the same thought. I think they'd be a good addition in my Yukons HE, too. It has 4 large tubes...
 
Exactly

Yeah, I had the same thought. I think they'd be a good addition in my Yukons HE, too. It has 4 large tubes...



I'm going to have a fab guy we use make some up for me. What do you think, just one for the larger center tube or some for the outer tubes as well?
 
@brenndatomu are you still running with about 50% of your secondary air cut off? I have been trying this over the last 4 days and it really seems to have evened out the temp. I seem to get longer secondary burns. It seems to have slowed the production of coals down as well. It's almost as if it is making the air go over the coals more.
 
I'm running with my secondary cut by 2/3. It does make a difference, but I'm not running a baro anymore.
 
I'm running with my secondary cut by 2/3. It does make a difference, but I'm not running a baro anymore.
Can you explain a little more? When you set your draft are covering the secondary inlets while the primary is wide open to get the proper draft. If I remember correctly you have a really tall chimney? Are you trying to cover both evenly?
 
I ended up covering the two outer primary ports on the damper door about 1/2, and the secondary ports are covered about 2/3. Basically I adapted the furnace to the chimney (32'). I've ran it now like that over a month now with success. John Gulland recommended a long time ago to try it, and I wasn't brave enough to do it at a time. I finally pulled the trigger. The damper itself also it set to open only a percentage as before. One thing to remember, the draft only spikes when hot. Once the damper closes, the flue temps drop and the draft settles.
 
I'm going to have a fab guy we use make some up for me. What do you think, just one for the larger center tube or some for the outer tubes as well?
I just did the center tube for now, mainly because it was quick and easy, I just wanted to see if it had any effect. Seems like it did so I may try to do the small tubes too. They will be a little trickier because only having half the opening available to install them. Also, since they are smaller it may be easier to block too much air flow...smoke out the door on reloads.
I was reading about the different types of turbs on this companys site, interesting http://fuelefficiencyllc.com/feturb.html
 
Might be a good idea to monitor both the temps of the supply pipes, close to furnace, and changes in flue draft, when trying turbs. They would both likely be affected - turbs would have the effect of (minimally) choking down the flow of exhaust gases, about the same way a key damper would.
 
Do you guys ever just consider these furnaces to be a big Magic Heat device?