Getting Frustrated with Temperature Control

[Satchelpig]

While I don’t have the same Kamado cooker or controller, let me suggest a fourth possibility. There is something malfunctioning with either your controller or your ambient probe. I have two different controllers and and have on two different occasions had something go wrong with the controller one time and the ambient probe another. For something like ribs which would fit into the 6 hour range at 225, you could test things by manually adjusting you vents. On my Big Green Egg that would mean starting a small fire in the center and adjusting the bottom vent open 1/4” and the pebbles on the top daisey wheel set at 1/2 to 1/4. Also, I use lump charcoal which produces less ash than briquettes. I would be interested in what you discover, since if I ever win the "Give Away" the SlowNSear Kamado
would be in the running.

Thanks. I can certainly test the probe to be sure, but as you can see from the attached photo — used with a pork butt done in a pellet smoker just a week prior that came out beautifully — it seems to measure consistently and logically elsewhere. Also, of course, is the matter of the fuel, which continued to burn.

[LA Pork Butt]

While I don’t have the same Kamado cooker or controller, let me suggest a fourth possibility. There is something malfunctioning with either your controller or your ambient probe. I have two different controllers and and have on two different occasions had something go wrong with the controller one time and the ambient probe another. For something like ribs which would fit into the 6 hour range at 225, you could test things by manually adjusting you vents. On my Big Green Egg that would mean starting a small fire in the center and adjusting the bottom vent open 1/4” and the pebbles on the top daisey wheel set at 1/2 to 1/4. Also, I use lump charcoal which produces less ash than briquettes. I would be interested in what you discover, since if I ever win the "Give Away" the SlowNSear Kamado would be in the running.

[Satchelpig]

I am new to using a Kamado, and after reading reviews, I bought the SNS deluxe earlier in the year with the idea of it being my primary charcoal-fueled device. In particular the ability to use it in "old school" Kamado style, as well as with a true 2-zone setup, held special appeal. As far as I could tell, the choices in that group amount to the SNS or Primo, and SNS is what I picked.

Since that time, I have found things I think it does particularly well (pizzas and kettle-style grilling), but I have thus far failed to use it effectively as a smoker, which is at least theoretically supposed to be a strength. I repeatedly hear that temperature control of Kamado is a supposed strength, but either I have totally failed to figure it out, or there’s something going on with my cooker that I need to solve.

Which brings me to yesterday and some ribs I ruined because I could not maintain a consistent, low-and slow temperature. I was shooting for 225-250, and as you will see in the attached chart, no matter how I set the vents, I could not get it there and keep it there. In hopes that someone might be able to help, I want to specifically explain how I set the cooker up, which I believe is consistent with the instructions I’ve seen for this and other Kamado grills.

(1) Because I was cooking 3 racks of ribs, I needed the full surface available, so I went into traditional Kamado mode.
(2) I filled the basket completely with Kingsport lump briquettes, and deposited two paraffin cubes, one left-center, one right-center, and lit them.
(3) After giving the coals 10-15 minutes to heat up, I put the diffuser plate over them, closed the lid, and put an ambient temperature sensor, connected to a FireBoard, and asked it to shoot for 250 degrees, but to alert me if the temperature went over 275 or under 200.
(4) My FireBoard is connected to a 12V fan that is securely installed into my lower vent. When I use it, I close the bottom vent entirely, and set the upper vent to a fairly low level — 1 or 2 at the most. In theory, this should allow the fan to regulate the bottom vent airflow to maintain a proper temperature.
(5) The result: total chaos, high temperature alerts all day and night, and overcooked, mediocre-at-best ribs with overdone bark, despite having started out looking promising. No matter how far down I choked the vents, I couldn’t get the temperature down. If you look at the chart I’ve attached, you’ll see that the temperature is moving all over the place.
(6) The most glaring illustration of this was post-cook, when out of curiosity I left my ambient probe in the cooker after all vents had been totally shut and the fan disconnected. What happened, as can be seen in the attached chart, is that the temperature actually went UP, dramatically, and stayed there for hours, not only not containing the temperature but wasting charcoal.

I can’t figure this out and need some help.

I have three theories.

(1) despite the tight seal on the 12v motor, there’s some way that air is getting through the lower vent even when it’s closed. The reason I don’t think that’s the case is because (a) I can’t find any evidence of that, and (b) the reason I added the blower in the first place is that I was having trouble maintaining consistent temperatures.
(2) There is something wrong with my technique that is not consistent with the instructions or good practice that I don’t understand.
(3) there is some kind of issue with the cooker that is enabling air into the chamber even when the vents are fully closed.

I would very much appreciate any tips/guidance advice, because I want to use this cooker to its potential and I’m frustrated.