Temp Fluctuation

[tiorio]

I bought a dyna glo 40 inch smoker and am using for the first time today. I’ve set the temp to 225. When it hits 225 the heating element goes off and the temp gradually falls. However it drops down to around 171 before the heating element comes back on. And then the process starts again. Is this normal?

 

[johnmeyer]

I have an MES, so I don't know how a Dyna Glo works, but in the MES, the chips are heated to smoking temperature by the same element that is used to heat the chamber. As a result, in order to get the chips to combustion temperature, the element has to get really hot, and has to stay hot for more than a few seconds. As a result, the unit is designed so that the element stays on for a lot longer than is needed to bring the smoker back up to temp after the element was last turned off by the thermostat. This creates really big temperature swings.

This is the basic nature of this design.

Fortunately, the food doesn't care much about these variations, although you do sometimes have to get creative in setting your temperature: if the highs get too high you can overcook the exterior, and if the average temp is not right, then your cooking times will be way off.

The solution is to re-engineer the unit. With an MES, the ultimate is to put in a PID controller which regulates the element so you only get 1-2 degree swings (and maybe less than that). However, this completely and totally stops the chips from "catching," so you also have to build a "mailbox mod" or some other external enclosure where the smoke is created and then delivered to the box.

For most people, they just live with the temperature swings, since it usually doesn't affect the cooking, and adapt their temps and recipes as needed.

 

[johnmeyer]

I wish people would stop with the PID nonsense. It isn't needed for smoking meat. The only reason it's there at all is because its just software so costs nothing to build into temp controllers. Since temp controllers are used for a wide variety of applications the makers put it in there to cover those applications and markets. High and low setpoints will suffice for smoking meat.
Just go try to find a PID controller used in any real barbeque joint that sells barbeque for a living. I doubt you'll find even just one.

If you read my post, I was not advocating that he install a PID, and only said it was the ultimate way to get near-perfect temperature control. I totally agree that it is total overkill for smoking, but I also must point out that many people in this forum do care and worry about the temperature swings, and therefore it is important to know what the options are.

Finally, installing a PID controller hurts absolutely nothing, and it will make it a little easier to be consistent from one smoke to another.

All that said, I am an electrical engineer and have actually designed and built analog PID controllers (back before digital). I could build one now, but am not tempted in the least because, as you imply, it is overkill.

 

[dr k]

I wish people would stop with the PID nonsense. It isn't needed for smoking meat. The only reason it's there at all is because its just software so costs nothing to build into temp controllers. Since temp controllers are used for a wide variety of applications the makers put it in there to cover those applications and markets. High and low setpoints will suffice for smoking meat.
Just go try to find a PID controller used in any real barbeque joint that sells barbeque for a living. I doubt you'll find even just one.

l didn't jump on the PID for tight holding temps within two degrees. That is the side effect of getting my smoker to 275 that ithe Mes is advertised to heat to and both My Mes gen 1 40 didn't get to. I gave one to my daughter and she uses the oem MB controller and I kept the other. My controller light switch turned off my smoker. Those two problems combined with lousy element lugs that failed in the first year got me to want to eliminate all oem pcb board/controller from MB. So a box, door and element are the only things needed from MB because their electrical components are pure crap. Most everyone I've dealt with going to PID have issues similar to mine with a horrible smoker not working, not the temp swings. Unplugging the PID and bringing it inside when not smoking makes perfect sense (another beneficial side effect of getting a controller that works.)

 

[tallbm]

I'm not trying to argue here because everyone has different perspectives that are valid.
My personal perspective on using a PID was to be able to effectively do sausage and bacon without causing Fat Out. I don't like the idea of having a smoker that is unable to smoke everything I would like to smoke :)
I was uncomfortable with my MES's 35F temp swings for doing those two meat items.
I hunt and spend a lot of time and effort processing my own meat and making my own sausage. I don't want to disrespect the animal and/or waste all of that time and effort making sausage just to ruin it with temp swings causing Fat Out.
Wild boar are animals I take almost every year and I make sausage with them but I MUST take the sausage to an Internal Temp (IT) of 165F to ensure micro-parasites are not an issue, which means walking the smoker up to a higher smoker than normal to hit that 165F. I have little margin for error doing those sausages so temp swings are the enemy here.

Again, we all have different perspectives and vantage points that are valid. This post is not meant to argue but simply to share on situations that others may not have considered and to expand all our knowledge on what possibilities are and why. I hope this info helps out