One temp fluctuates while others are constant???

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Brewsit
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One temp fluctuates while others are constant???

Post by Brewsit »

I've been trying to figure this one out and I'm out of ideas. I have one temp probe that fluctuates up and down as much as 10 degrees and never sits still. The other two are constant and normal. What I've ruled out:

BCS is grounded to AC ground
All wires are running together for the sensors, so it's not interference from AC
I switched each probe with one another, so it's definitely something wrong with the probe itself, not the wiring from the control panel to the BCS
probe wire run is identical to one of the runs that has no issues
All coefficients are correct and the same

The only thing different about this probe is that I put a slight bend in it near the base to get the angle I wanted... but this shouldn't have caused this kind of problem... should it?

The only thing I could think of is that I got sent a bad thermistor? Or am I missing something here?


I tried to upload an image of the data log but it says the file type is invalid. Just try to imagine two flat lines and one wavy one that goes up and down with no real pattern or consistency.
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oakbarn
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Re: One temp fluctuates while others are constant???

Post by oakbarn »

Bending wires on a themoristor is normally a no no
Brewsit
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Re: One temp fluctuates while others are constant???

Post by Brewsit »

So it's a 7" probe and the bend is near the base. It's a probe that was built by brewershardware.com... the thermistor would be down at the tip, correct?
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Re: One temp fluctuates while others are constant???

Post by JonW »

Really hard to say if the bend caused the problem, but the fact remains, you have one probe not working correctly and it's the one you tweaked.

You're probably going to just need to get a new probe. You might be able to get just the thermistor sensor and possibly re-make the probe. I don't know if the sensors are permanently potted into the bottom of the tube or not though.
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Re: One temp fluctuates while others are constant???

Post by Brewsit »

I'm gonna call them this week and hopefully get it figured out. If and when I do, I'll post the result in case anyone else runs across the problem. Until then, I'm still open to ideas.
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Re: One temp fluctuates while others are constant???

Post by Brewsit »

I talked to the guys at Brewer's Hardware, and they felt that the issue was a problem with the temp probe itself. I told them that I had put a bend it, but they did not feel that would have caused a problem. So, they are sending me a new one. It's nice to have such a level of service.

I also asked about just rebuilding the one I had, and they said that it was indeed potted into the bottom of the tube and would be pretty difficult to try to rebuild. Good info as well.
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