Curious as to what others are getting for plenum temperatures after firing a new load. How hot does your plenum get before your damper closes and you get a good secondary burn going? Want to make sure I am not getting it too hot.
Tundra 2 / Heatmax plenum temps
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Mrpelletburner
Minister of Fire
Depending on where in the cycle the fire is or if the unit is calling for heat, I get readings between 110f - 135f.
After there is a good char on the wood/have good rolling secondary burn happening. I don't have a temp controller installed so I have the damper open for about 15-20 minutes before closing. Plenum gets up around 200 degrees.
Mrpelletburner
Minister of Fire
Need to get a temp probe. Only have an external thermometer. 350 range on outside of single wall black steel pipe. Internal is roughly 2x external, correct?
Mrpelletburner
Minister of Fire
sloeffle
Minister of Fire
No idea about plenum temps. My furnace is however set to kick the blower on at 150 so I’d say they are in that ballpark. The Caddy has an adjustable snap disc.
I generally see flue pipe temps in mid 500’s when the damper is open. They then drop back to anywhere between 350 - 400 when the damper closes.
I generally see flue pipe temps in mid 500’s when the damper is open. They then drop back to anywhere between 350 - 400 when the damper closes.
They are basically the same internally, so sounds like its about the same. Is that 350-400 external or internal temp? Wish I could adjust the blower setpoints... if someone knows how on a T2, let me know!
sloeffle
Minister of Fire
There is no way to set temperature points on the t2 through the board.
I did find a way to lower the on off set point by adding a ohm resistor between the RTD and circuit board as a manual solution.
Stock tempurature turns (on at 125f off at 110f.) The resistor I added brings the off temperature to around 95f on at around 110f.
Wow, that's high. That the kick in temp for speed 3; overtemp is 250.
I've only been burning the T2a few weeks, but the highest I've seen is 165, and I had to try to get there, and I didn't have the nerve to go higher (flue temps a bit over 550F to get that plenum temp).
I suppose you could alter the temps the fan sees by moving the probe downward in the plenum.
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brenndatomu
Minister of Fire
That's getting up there for sure! IIRC the high limit switch would open at 200* on the T1 (closing the damper)
Mojappa
Burning Hunk
I easily bounce off 200° when firing a new load unless the stove is really cold. No idea what my flue temps are, really need some more data points to work with. Once the switch is flipped (usually about 20min after loading) it starts dropping back down pretty quickly. Not sure if this is due to a weak draft, still gotta get the Dwyer installed.
sloeffle
Minister of Fire
The Caddy has an adjustable snap-disc / fan limit controller. If I remember correctly the book says to have it come on at 150 and shut off at 100. That is what I have mine set to, as I found it works best for my house. I also have a speed controller on my motor.
EDIT: Please this post below for the actual verbiage from the manual
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Odd....why would SBI have the Caddy come on at 150 but the Tundra 2 at 125? 125 seems too low to put out any substantial heat. Unless they are just gun shy from all the T 1 cracking issues.
brenndatomu
Minister of Fire
I could rarely get my T1 up to 125*, but when I did it was cranking the heat out
JRHAWK9
Minister of Fire
FWIW, I know I have a different furnace, but mine kicks on at ~125° and off at ~96°.....speed controlled.
Kicking on at a lower temp doesn't necessarily mean once the blower kicks on you will see any lower/higher supply temps over the duration of the burn. A higher kick-on temp just means it will be storing more heat energy as thermal mass and/or radiant heat until the blower does kick on. It will then take a bit longer to strip this heat, but once it reaches equilibrium temp, the supply temps will be the same. Assuming both the 125 and 150 setting allows for constant blower run time. If the 150 setting also turns off at a higher temp and causes the blower to cycle, then that's different and the lower setting will deliver more BTU's due to the blower running more. That's how I see it anyway.
sloeffle
Minister of Fire
No idea. I do know the firebrick on the Caddy is a lot heavier from what folks have said. So maybe they want the brick to "warm up" more before the fan kicks on. I'm just throwing out ideas.
Here is the paragraph from the manual:
"FAN CONTROL The fan limit control setting may vary depending on the type of installation. The temperature setting “out of service” is preset at 110o F, the temperature setting “in service” at 150o F. and the high limit at 250° F at the factory. These settings should provide a proper operation for most installations.
It is preferable, for a prolonged operation of the blower, that the setting “out of service” be low enough. But a setting “out of service” too low will cause undesirable cold air circulation. To modify the settings, simply move the tabs to the desired position on the temperature dial of the fan limit control.
The adjustment of all controls must be performed by a qualified technician. The controls setting and the blower speed must conform to the recommendations of the “Warm Air Heating and Air Conditioning National Association”. For continuous operation of the blower, use the switch located below the fan limit control or on the electric unit which controls the low speed either at the “on” position or the “off” position.
It is not recommended to let the blower run on continuous mode when heating with wood since the wood furnace must reach a certain temperature before the blower starts in order to operate efficiently"
nellraq
Member
nellraq
Member
Hi Case,
I would like to change the on off settings forthe fan on my T2 as well.
Could you please provide the specs for the ohm resistor you are using. A pic of the set up and the resistor would be very helpful too.
Thanks
I would like to change the on off settings forthe fan on my T2 as well.
Could you please provide the specs for the ohm resistor you are using. A pic of the set up and the resistor would be very helpful too.
Thanks
I have a rebadged Caddy that I've been experimenting with. It has a 2 speed limit control with a constant speed 1 (can't hear it running) and once the plenum hits around 110 or 120 kicks into speed #2. So far I'm getting used to it. While it constantly circulates when the fire dies down, the house has been remaining warm over night. Once the register temps hit around 100 then speed 2 kicks in. I realize that the low fan speed doesn't cause any drafts....but I'm waiting till it gets cold to see how it does. In 30 degree weather I've seen 11 hour burns with the house at 74 which I can't complain about.
brenndatomu
Minister of Fire
Same unit. I have a 2 speed blower control. I have a wire on low with a set speed and my normal wire for on. I'm still unsure about when it gets really cold, but it's been doing okay lately. It just won't shut off....however in this weather the furnace stays running so it's okay. I've been running the 2 speeds about a week or two now and it's been working.
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