So I have mine hooked up to my chest freezer and it has been working fine for the past two months. Usually it only runs on the cool cycle until it reaches the set temp (3.9 C). Last night I noticed the freezer was still running while the temperature read 2.0 C, but the read dot was on the "heat" cycle. Seems strange to me, has anyone ever had this happen or any thoughts of the cause of this?
STC-1000 Question (ebay temp controller)
- Thread starter spenghali
- Start date
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Can you post how it is wired? If you did a single outlet and didn't break the hot side tab you could cause this.
JuanMoore
Getting the banned back together
Sounds like the cooling side relay got stuck in the closed position.
Yep, that would do it too!
OP
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spenghali
Well-Known Member
What would cause this? I fixed the situation by powering off for the night, then powering on in the morning. It chilled down to the set temp then turned off. My thought was that it had somehow chilled below my set 5 degree temp differential, then cycled to heat trying to warm the freezer, but since there was only a cool side hooked up, this just ended up running the freezer for a potentially infinite amount of time, (since the temp would never actually rise).
JuanMoore
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The most common cause is getting hot from excess current flow or frequent cycling, but sometimes it can happen for no good reason. What setting are you using for the compressor delay (F3)? What does the tag on the freezer say regarding start-up load and running load?
Did you just put something large in the freezer? You might get temperature overshoot if you just put a new keg into it and had the thermostat probe attached to the new keg.
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spenghali
Well-Known Member
Compressor delay is set to 5 minutes. It may have been from frequent cycling since people were in and out of the keezer more often over the holidays. I did not just put any new kegs in, and if I had I don't think it would make much of a difference because my probe is in a gallon of water in the middle of my freezer.
JuanMoore
Getting the banned back together
With your probe placement it shouldn't really matter, but it still might be a good idea to max out the compressor delay at 10 min. Would be helpful if the probe got pulled out accidentally or something.
If I were you I'd keep a close eye on it. If it happens again, you might think about replacing the controller, or at least the relay. I'd also check the plate on the freezer for the start-up draw. IIRC the relays in the STC-1000 are rated for 15A @110V.
JuanMoore
Getting the banned back together
4.7A is likely the running load. The start-up load should also be listed, and is probably much higher.
