No pipe temps that high are absolutely not efficient at all it is wasting to much heat up the chimney and is absolutely an over fire.
Not getting enough heat - New Drolet 1800 - Do I need a flue damper?
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You're correct. I keep mixing the two (stove pipe and chimney)...it's the downside of speaking French. In French, there is no difference.
I'm just a bit weary of putting holes through the double wall pipe. I never actually saw the pipe before it was installed, but, from what I am reading and seeing, it appears that the two layers are more or less sealed. Isn't there a risk in damaging the pipe by putting holes through both layers?
I don't actually recall if the flames were falling down, I was a bit too concerned with being unable to control the burn to pay attention. I do remember flames being shot out of the air tubes...so gasses were certainly being burnt.
To confirm, you're able to hit 750 STT without going above what temperature in your flue? I am not sure if it's possible to hit 750 STT whilst keeping the flue under 800, but if it is, that would be ideal. I assume that would be way more efficient since I'd be keeping a lot more heat in the stove.
I have never hit 750F on STT. Once or twice I have hit 625F. That only happens when the 'air wash air' ignites unburned gas. See video. I am trying to figure out how to get higher heat without the 'air wash air' igniting unburned gas.
Regarding putting holes in your double wall stove pipe, do you have a hole for your temperature probe? Are you planning on getting a manometer to measure your draft? I would suggest that you get one before you install a damper. I would think you would want to understand your current numbers, then decide what action to take. If you get a manometer, it is possible that your manometer tube will fit into your temperature probe hole. You could then get a draft reading without adding a hole. Then you could decide about the damper. I would only do this on a temporary basis.
If you go with the damper, I suggest the manometer be installed in it's own hole. Then you could adjust the damper based on the draft readings.
You could check with your installer regarding the holes required for a damper. Perhaps others here will chime in on their experiences.
stoveliker
Minister of Fire
Granted I have a different stove, but what is your concern about the primary air igniting gases as in your video? (You said you wanted a bit higher stt without having this type of flame - why?)
I see this regularly and I don't think there is a problem with it? (In itself, if temp limits in/on stove and pipe are kept.)
I see this regularly and I don't think there is a problem with it? (In itself, if temp limits in/on stove and pipe are kept.)
The air wash no longer cleans the glass. I get a heavy build up of creosote.
My flue temp is over 1000 F.
These pics are related to the video.
Man those flames look nice. I have only rarely seen that. My flames are considerably more agitated.
Your remark for the temp probe is warranted. Not having looked inside the stove pipe, I'm not sure how it's installed. It's likely just a drilled hole, but it could be "sealed", depending on how the probe is bolted to the pipe.
Once it warms up a bit and I can go a while without turning the stove on, I'll have a look inside the pipe and see.
You mentioned you were drafting too much and that Drolet recommends 0.02-0.04" WV. I assume this is a function of how hot the stove is. How did you know when to take a measurement? Or do you basically keep adjusting your damper to keep it at that value?
If you're hitting around 600F, are you still satisfied with the heat output? It only seems like the stove makes the basement "underwear warm" when the STT is above 600F.
EbS-P
Minister of Fire
FWIW my flames never get that lazy on my 1800i with 24’ of insulated liner and my damper full closed. I may need it closed to 80or 85 degrees and hits something I’m thinking liner maybe a screw. I may need to weld washers over the holes too. But to be honest I do like to see some blowtorch action on a hot burn with air full closed. But maybe that just me being very comfortable with my F400.
Does your baffle glow in spots? With out damper I had many. With damper just where the most active secondary flames are.
And I never get buildup on my glass unless I have a split really close or touching.
EbS-P
Minister of Fire
Before the damper, I did not have those lazy flames. Air from secondary tubes was rushing to front of stove and up flue.
My manometer is connected to my stove pipe. It reads continuously. I am always looking at it. I reviewed my notes. Drolet recommended .03 - .05 " Water Column. If I stated something else, I was mistaken. I let the draft run when I am starting up a fire. As the fire builds I start to adjust my damper to control the draft. I do not always have it between .03 - .05. Once fire is going well then I can adjust to that range. Using damper and primary air control, I can get draft to stay at one setting. For you, it will just take some trial and error. It is the learning process. You also can begin to 'read' the flames. Are they being sucked up the flue? What color are they? Are they lazy or intense? etc.
I rarely get to 600F. I can get to 540F easily. But I have only seen over 570F when the 'air wash air' ignites the unburned gas. I am trying to figure out how to get that elusive 625 without that happening. I am sure it will make the room warm up much quicker. I am not satisfied at 540F.
stoveliker
Minister of Fire
ok, I see. The flow/flames indicates your air does not go down the glass completely, in agreement with the creosote. In my stove, I can get that type of flames away by increasing the air flow (or snuffing out all flame). I do have creosote on my window but I don't have a problem with it - but my stove is good at "slow", so I'm used to it.
I (as others recognized before) see the problem that indeed you need more air flow to keep your windows clean, but your flue is already hot. A damper helps with the flue temps but would hurt the flow.
Baffle glows at a few spots. Usually where flames come out of the front secondary tube. Not from all holes, but some of them. As flame wraps around and goes up flue. I did not have them without damper. I hardly had any secondary flame from tubes. SBI informed me the air was moving to fast, did not get hot enough, and was sucked to quickly up flue. Damper slowed everything down.
EbS-P
Minister of Fire
I’m feeling a little better at keeping my flue gas at 950 at the damper in a the adapter and a STT of 625.
I really did not want my flue gas to be in the 900F range. I thought it was sending too much heat up the flue, and not using that heat to increase the STT. I read so much about high flue temps (say 750F and above) being too hot and that is the cause of low STT. Too much heat going up the flue.
I am starting to wonder now if that is what it takes to get a STT in the 625F range for these particular stoves.
EbS-P
Minister of Fire
I think they are very easy breathing by design. I should have said those were near my max temps on my last big load (right before they start to come back down) with the blower on 80%. I could cruise in the upper 800s.
Those temp really don’t feel like I am pushing the stove hard based on looking at the flames. I will say opening the damper 20 degrees results in an immediate drop in gas temps. But after two minutes it’s rising past where it was.
I played with blocking secondary air intake and the primary boost holes. My assessment was while that worked to reduce temps I had now way to reduce the air wash air and it was out of balance.
Whole thread got to go back and figure out what my damper was catching on as it could not go around a whole 360. A fender washer inside next to the liner worked. Don’t know what I gained but I feel like I did something.
My bad, I should have gone back to check your comments, instead of trusting my memory. You're correct about the setting for the water column.
It's interesting you're getting such a low STT. I can hit 500 reasonably easily on the 1800, by the flue outlet. I'm burning mostly ash. The only way I broke into the 700s was to stuff every cubic inch I could with wood. It took a while for it to ignite, but it sure warmed up the stove! This is what Drolet recommends in their instructions, however, I was clearly overfilling the stove based on the flue gas temps. If anything, that's my main motivation to get a damper, as I had no way to cool it down. I just sat there with my fingers crossed hoping it wouldn't stay above 1300 for too long.
You're correct about it warming the room up much faster. If I remember my blackbody radiation, power output goes up with the fourth power of temperature, in Kelvin. So, going from 500 F STT to 700 F STT should more than double the power output.
Just an update: My father in law gave me some maple that had been drying for 3 years in his garage. It tested at 16% humidity, vs 19% for my ash.
The STT still doesn’t break 550, unless I jam it completely full, at which point the flue temp hits 1400-1500.
The only advantage I’ve seen with the maple is that it lasts a hell of a lot longer and makes for very very good coals vs my ash.
Still can’t get the house up more than 23C, when it’s about 0C out.
On the bright side, I’m burning a lot less propane.
Still waiting for a damper. I’ll see from there.
The STT still doesn’t break 550, unless I jam it completely full, at which point the flue temp hits 1400-1500.
The only advantage I’ve seen with the maple is that it lasts a hell of a lot longer and makes for very very good coals vs my ash.
Still can’t get the house up more than 23C, when it’s about 0C out.
On the bright side, I’m burning a lot less propane.
Still waiting for a damper. I’ll see from there.
Edit: I got some of the posts mixed up, I'm referring to woodcutter Tom's low STT temps.
With my Escape 1800 I can hit 800 stove top without much effort. It would likely be at 800 or higher if my flue temps were as high as you describe for any length of time. My Escape is a pre-2020.
Yours is a 2020 compliant Escape right? Look up at the stovetop from underneath. Is there any insulation (i.e. piece of c-cast) under the stove top? My pre-2020 Escape there is nothing, just the bottom side of the steel. Just to clarify, I'm not talking about the baffle, look above the baffle at the stove top.
Reason I ask is because with the 2020 Drolet Legend, it has 1/2" c-cast insulation directly under the entire stove top. When I got my Legend it behaved much like you have described, I could run flue temps up well over 1000 and never break 600 in the center of the stovetop (much cooler on the edges). Keeping flue temps in the safer range (below 900) I'd barely break 500 STT in the center. With the c-cast piece removed the STT behaves much more like the pre-2020 Escape. It's also much easier to keep the flue temp in the safe range.
With my Escape 1800 I can hit 800 stove top without much effort. It would likely be at 800 or higher if my flue temps were as high as you describe for any length of time. My Escape is a pre-2020.
Yours is a 2020 compliant Escape right? Look up at the stovetop from underneath. Is there any insulation (i.e. piece of c-cast) under the stove top? My pre-2020 Escape there is nothing, just the bottom side of the steel. Just to clarify, I'm not talking about the baffle, look above the baffle at the stove top.
Reason I ask is because with the 2020 Drolet Legend, it has 1/2" c-cast insulation directly under the entire stove top. When I got my Legend it behaved much like you have described, I could run flue temps up well over 1000 and never break 600 in the center of the stovetop (much cooler on the edges). Keeping flue temps in the safer range (below 900) I'd barely break 500 STT in the center. With the c-cast piece removed the STT behaves much more like the pre-2020 Escape. It's also much easier to keep the flue temp in the safe range.
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I'll see if I can have a look in between the baffle and the stove top. I've never had a look there. I'm really hoping I'll find a way to get more heat out of the stove.
Are you hitting 800 on the entire top? I've managed to hit 760 right by the chimney, but that was with temps way way too high in the flue.
That's measured right in the middle of the stove top. I'm sure it's cooler near the edges. I use the Escape to heat a shop, so when I use it I'm usually looking for a rapid warm up, I try to peak the flue temps at 900. It's easy to overshoot though depending on the particular load of wood. That's where a flue damper comes in handy, at least you have some recourse if a load takes off faster than you thought.
Are those temps when you are running a blower or not?
Are you still planning on getting a manometer so that you can measure your draft? IMO it is important to know what you have and then make decisions based on those numbers.
Yes, mine is the 2020 compliant 1500.
I do not have the c-cast piece. Some one else asked about that last year. I do have a thin sheet of metal that is tack welded to the bottom surface of the stove top. Is there something like this on your 1800?
The stove generates heat. It just does not transfer it to the stove top. If I place my hand about 2 inches from the glass in the door, I can not hold my hand there for 2 seconds. If I place my hand 2 inches above the stove top I can hold it there until I get bored.
Do you have the same shaped deflector as I have on my 1500? By deflector I am referring to the \___/ shaped piece in the pictures.
EbS-P
Minister of Fire
My 2020 1800i has that thin tacked sheet. I’m assuming its stainless but could be wrong. No c cast.
brenndatomu
Minister of Fire
I used to have a Drolet Tundra (gen 1) wood furnace and it had a thin sheet of stainless tacked to the underside of the "stovetop"...other owners said that theirs did not have that sheet...what was interesting (in a REALLY annoying way) was that I could never get the heat out of that machine that other owners said their Tundra's would make...I always wondered what would happen if I removed it...never did though. I've had opportunity to play with one of their new Heat Commander furnaces here recently and it does not have the stainless sheet...it also makes way more heat than that old Tundra did too! Hard to directly compare them though, even though its basically the same firebox, the controls are totally different.
That's really unfortunate, I thought the 2020 2.4cuft SBI box escaped having the stainless sheet welded in like other models, guess that's not the case.
Unfortunately the complaint of high flue temps, and low stove top temps are not the first on here for SBI models that have that stainless sheet. I find it difficult to believe that this stainless sheet is not the cause. I'm definitely less inclined to recommend these stoves to other members based solely on this design.
@marty319 does your 3300 also have a stainless sheet tack welded to the underneath of the stovetop?
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