SOS - Mid brew STC-1000 temperature controller giving massive temp read errors??? 85c+

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Nick the Knife

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Murphy's Law has kicked in - I've used this temp controller with zero issues for several years (only around 20 times used!) - just put a brew down 2 days ago and walked past and noticed the temp controller was saying it was 85c temp!!! Opened up and it was colder than it should be - due to it cooling unnecessarily.

I've powered off - reset, checked the settings - all appear fine. Googled and seems no easy solutions or known problems. As far as i can guess is a possible probe issue.

1) Anyone know where to buy a suitable replacement probe for one of these units? Checked Jaycar and they don't seem to have.

2) Any other ideas on how to fix?

LHBS sells temp controllers for $90 - but I will not pay that - any ideas on the issue pls let me know.

Thanks in advance.
Ugh.....well emergency averted for now.

It was definitely the probe that had just shat itself - which is amazing as the whole unit is in a project box and the probe is external only, all taped to the brew fridge - literally never moves more than a few cm - but its just kaput.

I unwired the prob connections and rewired them up - no good. Reversed them - no good. Now I had 2 other shittier temp controllers I use for making yogurt - so I yanked one of the probs off one of them and wired it into the STC-1000 - bingo!

All working again and seems that THANKFULLY it hadn't been erroneously reading high temps (was reading up in the 90's) for long as my fear was it'd stall/freeze the brew - as my brew fridge is actually a modded bar freezer. So could have been a complete disaster.

If anyone know where you can order new probes - I'd still welcome that info - otherwise I'll have to order another one of these cheaper TC's and salvage from it.

Close call but good reminder to check on your brew each day as glitches and faults do occur and could cost you an entire brew. I'm honestly fastideous and there's no reason at all it should have erred like this . Cheers, Nick

PS. I recalibrated using the icecube method - found out the emergency replacement probe was reading about 1.1c higher than actual - so used F4 to get that back to zero'd.

Seems you need a 10k NTC probe 3435 - so ordered one of those:
Much thanks
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I have the probes die on me, I have purchased new ones off EBay. Just make sure the length is correct for your application.
STC1000s are extremely cheap Chinese crap that usually do a very good job and are sub $20. Have had a few temp probes die on me and you can order replacements on Ebay.
Problem is, if they fail and you don't notice, it could cost you a brew.
I have changed mine over to Inkbirds now- about $60 each but proper sealed units (no dodgey 240V wiring) and seem to last longer with lower failure rates.
I think it's a small and worthwhile investment but can understand the appeal of the STC1000. I just prefer to not risk 50L of good brew for the sake of an extra $40.

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