MES overheating

[mgthomas3]

Hello to all. This is my first post and I apologize in advance if this has been discussed but I've searched the forum and haven't been able to get the info I believe I need.

I have a MES Model 20070910 that has worked perfectly since I bought it in 2015 . Beginning last week when I set the temp on the controller to 220 degrees the smoker kicks in and runs the temp to upwards of 280 degrees. I have verified this by placing a separate thermometer in the smoker. All the while the controller reads 300 degrees.

I bought a new controller from Masterbuilt and when I use it, the exact same thing happens.
I replaced the rollout switch ( overheating sensor ) and that made no difference.
I cleaned the interior temp probe within the smoker.
Some posts talk about a relay being stuck open but where would that be?

Any help would be greatly appreciated. I really don't want to bypass the MES electronics and buy an expensive controller.

 

[dr k]

When the relay in the bottom of the smoker clicks for the closed circuit when you start heating, it heats, then opens the circuit at set temp but it may stick in a closed circuit position or if welded closed from a failed relay in the stuck closed position you'll never hear it click opening and closing at set temp, mainly when closing to heat. It just continues to heat until the round dime sized safety thermal switch on the back wall opens the circuit. Sounds like a PCB issue. tallbm has the simple no back removal PID controller fix that many of us have done so you'll never buy a new smoker as long as you have a heating element, door and box. I have a spare element as well.

 

[tallbm]

Hello to all. This is my first post and I apologize in advance if this has been discussed but I've searched the forum and haven't been able to get the info I believe I need.

I have a MES Model 20070910 that has worked perfectly since I bought it in 2015 . Beginning last week when I set the temp on the controller to 220 degrees the smoker kicks in and runs the temp to upwards of 280 degrees. I have verified this by placing a separate thermometer in the smoker. All the while the controller reads 300 degrees.

I bought a new controller from Masterbuilt and when I use it, the exact same thing happens.
I replaced the rollout switch ( overheating sensor ) and that made no difference.
I cleaned the interior temp probe within the smoker.
Some posts talk about a relay being stuck open but where would that be?

Any help would be greatly appreciated. I really don't want to bypass the MES electronics and buy an expensive controller.

Hi there and welcome! dr k nailed it.

The circuit board in the bottom side (yep underneath side of your smoker) seems to have it's relay switch stuck in the on position.
It is pretty much impossible to get a replacement circuit board.

Unless you are one of the few people who knows circuit boards and components well enough to replace that part, your only real repair option is to do the simple MES rewire and use a PID controller.
The good news is this will make your MES into a brand new beast of an electric smoker. Better than electric smokers that cost over $1,000!!!
I always say its like turning a golf cart into a Ferrari.

The not so great news is that a ready to go Auber PID controller will run you about $160. In perspective, this is still way less than a brand new smoker of almost any kind AND you will have a smoker that is like a bajillion times better than anything Masterbuilt makes new or anything under about $1,200 that will perform the same.

If you go this route it is best to also replace the crappy wire connectors that mastebuilt uses with some way better quality hi-temp ones that wont corrode and rust away on you. With the rewire, a pid congroller, and new connectors, you will be able to keep your smoker running through anything short of it being hit by a car.

Here is the detailed thread on the simple rewire job for using a ready to go PID controller to run a rewired MES. All us PID MES guys wonder "WHY DID WE WAIT THIS LONG TO DO IT?!" hahahah:

MES Rewire Simple Guide - No Back Removal Needed!!!

Lately I've seen a number of posts about guys wanting to rewire their MES. I had wanted to post a quick and simple guide for those out there that are curious or those that simply need to rewire but need a little assistance. Well here goes. Disclaimer: When messing with electrical equipment...

www.smokingmeatforums.com

Ask any questions you may have. You can get it up and running and way better than before if you want :D

 

[mgthomas3]

When the relay in the bottom of the smoker clicks for the closed circuit when you start heating, it heats, then opens the circuit at set temp but it may stick in a closed circuit position or if welded closed from a failed relay in the stuck closed position you'll never hear it click opening and closing at set temp, mainly when closing to heat. It just continues to heat until the round dime sized safety thermal switch on the back wall opens the circuit. Sounds like a PCB issue. tallbm has the simple no back removal PID controller fix that many of us have done so you'll never buy a new smoker as long as you have a heating element, door and box. I have a spare element as well.

Thanks for your reply.

Wouldn't this replacement circuit board take care of the problem?

Amazon.com

 

[tallbm]

Thanks for your reply.

Wouldn't this replacement circuit board take care of the problem?

Amazon.com

Holy crap! The 3rd party market is catching up!!!

If it matches your number then I guess it should work. I mean these things seem pretty much the same per MES unit unless you have the fancy MES with additional heating elements.

If it works it should get you back to square 1. It won't be anything like the performance of a rewired MES + a PID smoker but hey it's good to have the part available on the market. It's been since the pandemic since the parts dried up.
Feel free to give that a try and please report back!

 

[Bobnrtp]

Your model is the last one listed so it may work. I have the same model that you have and it looks like a different board. I had this same problem with mine a few weeks ago and like you didn't want to spend the $$. I did break down and got the Aubor PID. So glad I did. I set the temperature at 225 and it stays at 225. It comes with 2 probes one for smoker temp and one for meat temp. If you go the circuit board route let us know if that fixes the problem.

 

[tallbm]

Your model is the last one listed so it may work. I have the same model that you have and it looks like a different board. I had this same problem with mine a few weeks ago and like you didn't want to spend the $$. I did break down and got the Aubor PID. So glad I did. I set the temperature at 225 and it stays at 225. It comes with 2 probes one for smoker temp and one for meat temp. If you go the circuit board route let us know if that fixes the problem.

The PID life is a whole other wonderful world aye :D