MES heat control

[hotfishtacos]

I've read numerous threads with interest regarding the poor heat control on gen 2 MES smokers since I believe my 30 is gen 2. Although most everything I've smoked has turned out great I do notice that food on the left side of the smoker always finishes first, about 10 degrees hotter when done then the right side and the shelf temperatures are all over the map.  Today I fired up my MES 30, put my Maverick probes inside suspended on the middle shelf with a wet brick in between for load and set it at 275.  The water pan is empty. The left side overshot to 309 and the right to 301....again colder on the right side. After about an hour I turned it down to 225 which is where I cook the most and the temps both dropped to 225.  My next test with be to remove the water pan and add the ANMPS over the opening where the water pan was.  I will fill the ANMPS about 1/2 full height, one row for testing.  Let's see how much it heats up the MES and the effect on each side....Stay tuned...BTW, the Maverick probes are now registering 210 with the control still at 225...so it in now undershooting low...

 

[hotfishtacos]

..OK..I installed the ANMPS on the bottom left after removing the bottom drip tray and replaced the water pan. ..with the MES smoker set at 225 with my ANMPS burning the temps are 250 and 252.. I'll monitor for the temps for 30 minutes to see if it goes up or down...it is dropping slowly..., now at 210 and 212....undershooting again...the ANMPS is apparently not overheating the MES.  This is also what I was looking for..whether I need the Mailbox mod or not...for a 225 set-point... the answer is NOT so far..it is now at 225 and 228...climbing...now 230 and 232...having trouble managing temps at the setpoint...235 and 237..where is the temp control????? It is overshooting and undershooting on its own...

Now I am going to move the ANMPS to above the opening for the water pan and remove the water pan..and then watch the temps...after 30 minutes it is at 214 and 215...set-point still at 225... what I am not seeing which I was concerned about is a big temp difference from side to side with the ANMPS located above the drip-pan hole...this means the ANMPS is not heating the left side excessively and the ANMPS can probably be located there  successfully...so far no need for a mailbox mod when cooking at 225...now overshooting to 230 and 234...it seems to be marginally controlling temp..I see a PID controller in my future!...then when the temp is controlled we can balance temps in the chamber if needed.  I plan to re-run this test with the MES turned off...like for smooking cheese and see the impact of the ANMPS on overall temps and side to side temp balance as well..now both at 226...Later!  

Steve

 

[redheelerdog]

Good test info.

The MES 30 Gen 2 will never have good heat control without PID. It does do one hell of a good job smoking though.

The amount of chips (if your using the tray), moisture density and even AMPS amount filled can have an affect on different temperatures.

Try your tests in the morning, afternoon and then evening, they will all be different. Also, the wind affects how much temperature dissipates or stays inside.

PID her if you want better control, there are lots of threads on the subject.

Have fun!

 

[bauchjw]

Thank you Steve, great info and meticulous research!

 

[hotfishtacos]

..continuing my testing...I put the ANMPS in my MES 30 with one half full single row of pellets on top placed on the water pan opening with the water pan in no water and no power and wanted to see the effect of the ANMPS on chamber temperature by itself..I am interested in smoking cheese and don't want much heat...both Maverick probes started at 88 degrees and went up to 106 and stayed there after introducing the ANMPS...so I am seeing about 18 degrees added by the ANMPS...so I probably need a mailbox mod for cheese.  

BTW, this was a big day for me because I just received my new gen 2.5 Cabela's 40" Black MES smoker.  While testing the 30 I was assembling the 40 and now have it fired up and am mapping the MES temp against a pair of Maverick probes in the center rack right and left...with a brick in the middle for load..the chip pan backed out half way...First of all I really like the Bluetooth on my phone showing me the meat and box temps and I can also adjust it from my phone...very cool!..I set it at 275 to season the unit and after about 20 minutes the MES thinks it is at 207 but the pair of Mavericks say 239...and all those probes are within about 8-10 inches of each other...not very good!...but the Mavericks will be my gauge for cooking. I'm thinking the large flat metal surface of the smoker near the MES probe is probably having a heat sink effect on it...my Mavericks are out in the working are of the unit....now the MES says 235 and the Mavericks say 274...40 degree difference.  If I incorporate a PID controller this whole issue will go away.  What I am seeing is the same temp right and left.  My MES 30 has an average 10 degrees difference between sides.  The new gen 2.5 design seems better...time will tell.  The MES now thinks it is at 247 and the Mavericks say 288 so I am predicting a significant overshoot by the time it stabilizes.  This all tells me to always turn on the MES smokers and let them stabilize at temperature before loading them..now MES sees 262 and Mavericks see 302...BTW, the MES also has a meat probe which I placed right next to the Mavericks and it is reading about 10 degrees lower than them. The MES just hit 275 (the set point) and the Mavericks are at 316!..41 degrees difference!...The Mavericks are holding around 317 while the MES keeps rising...now at 292...I think that heat sink effect from the chamber wall is happening here..the power is off but the probe near the wall in the only one still rising..

Conclusion on my new MES 40 gen 2.5:

1. Temperatures seem to be balanced right and left..on the center rack..this is good

2. The MES controller is not accurate and I suspect that it may be attributed to the location of the probe, I do have my Mavericks to know what is really happening.

3. I need PID control for both MES units if cooking temperature is important and I don't want to continually chase box temperature.

4. I sure like that it came with 6 racks!  I'm cooking a pork butt on Sunday!

I plan to also do the ANMPS test in the MES 40 but suspect that heating will be at least 10 degrees...less because the 40 has a lot more mass.

I see a mailbox mod and a PID in my crystal ball...

Steve  

 

[hotfishtacos]

... there is more...I've been running my new MES gen 2.5 40 for about 3 hours now at 275 set point but the actual box temp is running at 295 to 300 so it is running hot.  The spec on the MES states +- 15 degrees accuracy on the smoker temp and +- 5 degrees on the meat probe...a PID heat controller is in my future...

 

[Bearcarver]

Hi Steve,

A PID can give you a more accurate Smoker temp, but all you really have to do is figure out how much the Maverick temp differs from the MES reading, and adjust your MES setting to get the Mavericks to the Temp you want.

Like with mine, at the temp I often use (230°) my Mavericks read about 15° higher than the MES reads, so when I want to smoke at 230°, I just set my MES at 215°, and my Mavericks will average about 230° once I get it settled down.

As for the overshoot on initial start-up or during a big temp setting change, that is mostly because the Mavericks are more sensitive and quicker to change. I have found that is easy to fix by using the method I posted awhile ago:

Like This:

http://www.smokingmeatforums.com/t/208552/avoid-temp-swings-in-mes-by-bear

Once you get the hang of it, this becomes quite easy to get & keep the smoking temp you want, and keep it averaging your preferred smoking temp.

They're all a little different, but easily controlled.

Bear

 

[hotfishtacos]

Great tips Bear!  My MES 40 runs hotter than the Mavericks at higher temps by about 20-25 degrees so I will compensate as you suggested.  BTW, I made my mailbox mod and it work great!..some test cheeses going right now...2 pork butts planned for tomorrow in the new MES 40.  Many people use hickory but I usually use a blend of pecan and cherry. I've got the pellets blended for this run.  

Steve