MES MB20072816 Not Heating

[UncleRichard]

My masterbuilt smoker stopped heating and I have not been able to fix it. I've had this for probably +5 years and it's awesome until now. Stumbled around the internet and found this forum. Here is what's going on..
-Heating light is on at the control panel but doesn't heat
-I can hear the circuit board click when setting the temperature
-Replaced control panel but didn't fix
-Replaced element but didn't fix. Verified old element 12.2 and new element 12.0ohms. New element is in it. Did not replace wire connectors at element because they were not corroded in my opinion. Didn't appear to be any major heat damage in the element compartment area.
-Verified no voltage at elements when it's on and no voltage on the red/black wires connecting to the circuit board.

It would be appreciated if someone could point me in the right direction.

 

[smokerjim]

Safety rollout switch?

 

[chopsaw]

Change out the connectors . 5 years old it's time . Could be when they get hot they disconnect .
I had that happen .

However , problem might be the limit switch / snap disc is shot . That's the round , flat looking thing on the back wall . Depends on what model you have on the location .

Also , some of the newer models have and access panel on the back to get to the wires for the limit . If not you'll need to cut one .

You could take the wires off the element ( unplug it first ) and do a resistance check for continuity when cold . Not sure if that works though . Best way would be to access the back of the switch . Check the wires , and do an ohm check at the terminals .

 

[UncleRichard]

Change out the connectors . 5 years old it's time . Could be when they get hot they disconnect .
I had that happen .

However , problem might be the limit switch / snap disc is shot . That's the round , flat looking thing on the back wall . Depends on what model you have on the location .

Also , some of the newer models have and access panel on the back to get to the wires for the limit . If not you'll need to cut one .

You could take the wires off the element ( unplug it first ) and do a resistance check for continuity when cold . Not sure if that works though . Best way would be to access the back of the switch . Check the wires , and do an ohm check at the terminals .

Okay. I ordered new temperature limit switch and connectors from Amazon. Will have them Monday and will post results.

Have to order the switch regardless due to breaking the connectors off!!

 

[UncleRichard]

It was the temperature limit switch!!!! Bought a pack of 6 for $7 on Amazon ( KSD301 250v 10a 150c) but I can tell they are Chinese poop because the wire connector came off. Also replaced the connectors for the heating element..

Know of any USA made limit switches or at least better than China?

Thanks guys.

 

[normanaj]

Know of any USA made limit switches or at least better than China?

There are better ones I just can't find the thread.I'll tag tallbm as he was the one who posted the thread.

 

[tallbm]

It was the temperature limit switch!!!! Bought a pack of 6 for $7 on Amazon ( KSD301 250v 10a 150c) but I can tell they are Chinese poop because the wire connector came off. Also replaced the connectors for the heating element..

Know of any USA made limit switches or at least better than China?

Thanks guys.

Hi there and welcome!

The only "better" you can get is to get ceramic switches. Just know that if you wiggle the tabs on the switches AT ALL (where they connect to the back of the switch) the switch will likely melt down on you after a while (months maybe). So I found it best to gently get the connectors on the switch THEN crimp/solder the wires to the connects, THEN fasten it to the MES hahaha. This way there was less tension on the witch while working with it.

If all else fails you can just wire around it but WARNING you are cutting out the safety switch from the mix so you should be sure to have a lot of working thermometer probes to rely on to know your smoker isn't running over on it's heat up.

Now that you are digging into your MES a bit more, you can go down the wonderful rabbit hole of the simple rewire and using an Auber PID controller to control it and make it perform 100x better than anything masterbuilt makes brand new.

If that interests you then these 180C ceramic safety limit switches would also allow you to do 325F smokes since the PID controller is not limited at 275F max. I just make sure I never go over 325F smoker temp and never at that temp for more 4 hours. This solves all my rubber/leather chicken and turkey skin issues :D

For under $13 USD here is an 8 pack of ceramic that go 180C/356F:

https://www.amazon.com/uxcell-Thermostat-Normally-Temperature-Microwaves/dp/B0DMZ9Q3G3/ref=sr_1_5?crid=2JQ8FBZ87YITY&dib=eyJ2IjoiMSJ9.KV74e4QG-pJcygrImXPtvEbyWkIWinXrB6-VgigKoAEEV_g_Fhx5OX0dQDC_kubsNrMpN2F8dzT5zklli6ARhRIsF3f4OirJN9f6UlD-7qV__WA-X80kjIMRNnCqizpvR75K-sag-NqA3FZW3J8sjN4lwhioxebU7Khlo-ZCHt_TBJi6YeT49UGk7p-cNyFYp3ONS_jGE0uY7p2bhretAZ4L-kA7vBwtX0j3mXrhapw.t3SZtZSLpmuicRtXQTfJaTMZVp82aclO9bc1GluZ3Ik&dib_tag=se&keywords=ksd301%2B180c%2Bceramic&qid=1746567107&refinements=p_85%3A2470955011&rnid=2470954011&rps=1&sprefix=ksd301%2B180c%2Bceramic%2Caps%2C121&sr=8-5&xpid=k4FaMrk0WN2mY&th=1

In any case ceramic switches are a little more robust since there is less plastic to actually melt in those switches where the connector tabs fasten to the back of the switch. You can find ceramic switches in lower temps as well that will work fine in place of your plastic ones.

I hope this info helps :D