MES 40 heating.. but not

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rhaugle

Smoke Blower
Original poster
Apr 10, 2015
113
16
Hi guys....I have a new heating issue.. my mes is about 4 years old, have replaced the coil once already. The unit heats up, but not to temp. I will set it to 230, and it only gets to about 145. So I jacked it up to 275, and it only got to 175. The unit "thinks" it's to temp, as it shuts off the coil eventually. I have verified these temp issues with 3 different thermometers...
Again, set to 225, only reaches 145, coil shuts off. Display reads 225. Raised to 275, heats to 175, coil shuts off and display says 275.

Thoughts?
 
Hi guys....I have a new heating issue.. my mes is about 4 years old, have replaced the coil once already. The unit heats up, but not to temp. I will set it to 230, and it only gets to about 145. So I jacked it up to 275, and it only got to 175. The unit "thinks" it's to temp, as it shuts off the coil eventually. I have verified these temp issues with 3 different thermometers...
Again, set to 225, only reaches 145, coil shuts off. Display reads 225. Raised to 275, heats to 175, coil shuts off and display says 275.

Thoughts?

Assuming the heating element is still good, you have a failing controller or thermal probe. You can replace your old controller with a newer one and that should fix the issue.

JC :emoji_cat:
 
This may be a long shot but it did happen to me.The built in temp probe on the back wall on mine got so munged up it that my MES would not heat up to set temp.A little degreaser and a little chunk of scoth-brite and I was back in business.

Most of these issues tend to be electronic in nature but it only takes a few seconds to give that probe a quick cleaning.You never know.
 
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Assuming the heating element is still good, you have a failing controller or thermal probe. You can replace your old controller with a newer one and that should fix the issue.

JC :emoji_cat:
The element heats up just fine (red hot), so I'm thinking that's fine.. hoping it's not a control board
 
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This may be a long shot but it did happen to me.The built in temp probe on the back wall on mine got so munged up it that my MES would not heat up to set temp.A little degreaser and a little chunk of scoth-brite and I was back in business.

Most of these issues tend to be electronic in nature but it only takes a few seconds to give that probe a quick cleaning.You never know.
I will definitely check this! I hope it's this.. but I have a feeling it's not.
 
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I will definitely check this! I hope it's this.. but I have a feeling it's not.

It can't hurt to clean it.

If it is a bad controller consider going the PID route.I know when mine goes that's exactly what I'm doing.
 
The element heats up just fine (red hot), so I'm thinking that's fine.. hoping it's not a control board

You can get a new controller for under $100. I make PID controller kits for single burner MES smokers.

JC :emoji_cat:
 
Hi guys....I have a new heating issue.. my mes is about 4 years old, have replaced the coil once already. The unit heats up, but not to temp. I will set it to 230, and it only gets to about 145. So I jacked it up to 275, and it only got to 175. The unit "thinks" it's to temp, as it shuts off the coil eventually. I have verified these temp issues with 3 different thermometers...
Again, set to 225, only reaches 145, coil shuts off. Display reads 225. Raised to 275, heats to 175, coil shuts off and display says 275.

Thoughts?

One thing not mentioned and something I have personally experienced is that your rollout safety limit switch is cutting power to the element.
This happens when it is overheating at the switch due to the wire connectors corroding away.
See when there is a bad connection that causes resistance which causes heat.
So if the connectors to the safety switch are heating the switch up due to bad connection, the switch gets hot after a period of time and hits its limit and cuts power.

If you have a panel on the back of your MES about halfway up (right hand side for MES40, sometimes middle location on MES 30) you can go in there and check the connections and u will notice if they are corroding away. This is a SUPER common failure point on MES smokers.
If you don't have a panel well you have to drill out the rivets on the back of the MES and pull the back up/off and that will get you to the houseing and then to the switch to check. I would cut and create a panel in this case to avoid having to pull the back off again. You refasten the back with #12 self tapping hex head sheet metal screws (3/4 inch long) and its all good.

NOW if your safety rollout switch is ok and the connectors are bad, you replace with hi temp stainless steel 16AWG female spade connectors.
If the switch is showing signs of damage (melting, burn marks), then I would bet $100 it fails soon too. You can either replace it or you can just cut the wires and splice them together and boom you are back in business BUT without a safety switch in the mix. I've had to do this to finish a smoke cause I've had like 5 switches melt down on me. They are delecate so you cannot bend or wiggle the tabs at all or it will fail after some time.

So before you go and by controllers and heating elements check your connectors here, at the heating element, and even underneath on the controller board.
My money is on the safety limit switch connectors causing the switch to overheat... its happened to numerous people here (and many times to me) and is a simple fix... especially if you already have a panel :D
 
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I was having issues as well.
A customer service representative told me to turn on the controller, do not set anything.
Take a lighter or torch and direct the heat to the little probe on the back wall.
The controller temp should build to325 then shut off. Let it cool down then give it a try as you normally would.
Not sure this will help but it worked for me a few years back.
Good luck and keep us posted as to what finally resolves the issue.

Oh. I guess this procedure resets the controller.
 
Ok. I tried the temp probe cleaning/burning and it did turn off with an ERR1 display code. Waiting for the unit to heat now.. will see..
This may be a long shot but it did happen to me.The built in temp probe on the back wall on mine got so munged up it that my MES would not heat up to set temp.A little degreaser and a little chunk of scoth-brite and I was back in business.

Most of these issues tend to be electronic in nature but it only takes a few seconds to give that probe a quick cleaning.You never know.
I was having issues as well.
A customer service representative told me to turn on the controller, do not set anything.
Take a lighter or torch and direct the heat to the little probe on the back wall.
The controller temp should build to325 then shut off. Let it cool down then give it a try as you normally would.
Not sure this will help but it worked for me a few years back.
Good luck and keep us posted as to what finally resolves the issue.

Oh. I guess this procedure resets the controller.
 
Cleaning off the temp probe seems to have fixed it for now...

But now, it's taking forever to heat... An hour to get to 270. I did have to replace the coil a while back, could this heat issue be related to poor connections to the coil?
 
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Cleaning off the temp probe seems to have fixed it for now...

But now, it's taking forever to heat... An hour to get to 270. I did have to replace the coil a while back, could this heat issue be related to poor connections to the coil?

It is either bad connection at the heating element or a bad heating element. IMHO

JC :emoji_cat:
 
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