Direct Wiring of STC-1000 For Chest Freezer

[rodwha]

I won't be wiring the heat as this will stay indoors, and so I don't see the need to wire it up the way the instructions videos show.

Can anyone point me to a nice direct wiring of the STC-1000 using the internal wiring? The one I found he vaguely describes it but doesn't show what he's doing.

 

[rodwha]

I pushed up my sleeves and figured it out. I was a bit unsure, and wanted verification before I cut wires, but it was just the uncertainty that made me hesitant.

Plugged in and working though…

:rockin:

 

[rodwha]

Set it for 17.2*C with a 0.3* differential, and it stopped at the right time, but has since dropped to 10.5*C. Is this because it was at room temp to begin with and just took so long to drop?

With a set temp of 63*F a drop to 51*F will certainly stall my yeast!

I'm going to keep an eye on it to see what happens now that it's been chilled a bit to see what it does.

I'm guessing an air temp like that won't be quite as devastating though as it would likely take quite some time for it to change the beer's temp. Right?

 

[WayFrae]

Is it still running even when it is at 10.5C? Just to make sure, the temperature probe is inside the chamber right?

 

[Lemontato]

If you have strapped the sensor to the fermenter and insulated it from the rest of the freezer, this is normal since the temperature of the wort will take much longer to be affected by the ambient temp thus keeping the freezer turned on until the wort falls to the target temperature.

 

[rodwha]

It turns off at the set temp of 17.2* C, but continues to drop. Now that it's been running it drops to 14.9*C or ~59*F (set at 63*F).

I'll certainly be trying this on my test batch first!

I'm wondering how insulating it and reading the fermentor temp instead will effect it as it takes much longer to change beer temp.

 

[rodwha]

Probe is in the chamber dangling about 1/2 way down.

 

[rodwha]

I'm thinking setting it for 64-5*F is better as it just won't let it get too warm, whereas if I set it lower I could accidentally stall the yeast (US-05).

 

[Sanjuro]

I just got 2 of these for my freezers. One for the Kegs I keep at 35 and one for the fermentation chamber that i keep at 66, then drop down to 34 for cold crashing.

http://www.johnsoncontrols.com/cont...nglestage/multipurposea19series/a19nema1.html

 

[danath34]

^ I think you'll have the same issue with those Johnson Controls controllers as well, unless they're using PID logic rather than simple on/off. I don't think they're PID controllers.

I think the issue is probably where the probe is.

OP: the probe is dangling in air inside the chamber? It's not in any liquid or insulated in any way? What's happening is when the probe reads the correct temperature (your setpoint) it turns off the fridge. But the air that is closer to the coils is going to be a lot colder than the air around the probe, and after a little bit of time, the temperature will even out more, which means the air at the probe will get colder, even though the fridge is off. The air inside the fermentation chamber is going to swing a lot like this unless you install a fan to circulate air.

The better way to monitor the temperature is to try to monitor the temperature of your beer instead of the temperature of the air around the beer, as the huge amount of liquid is going to buffer out the temp swings more, and change temperature a lot less than the air around it does. What I do is tape the probe to the side of my fermenter with a pretty thick (probably 1.5 inches) layer of bubble wrap and packing foam on top of it. Tape it up nicely so air cant freely circulate around the probe, and you should be measuring the temperature of the outside of your fermenter, which should only vary by a couple degrees from the center (warmest) part of the beer.

*edit*

I keep my probe on the fermenter as described above, but I also like to use another probe to monitor the air temp inside the chamber, mostly for ****s 'n giggles. On a cooling cycle, I have seen the air drop to the 30's, yet the beer stays right around my setpoint. That much liquid is slow to change temperature and won't match the air temp at all. So don't worry much about the air temp.

 

[rodwha]

I cut a large section of styrofoam and have considered forming it to the bevel of the fermentors and creating a pocket for the probe to sit in and taping it with duct tape I suppose.

I do have some bubble wrap too if I can dig it out of the recycle bin.

 

[Sanjuro]

^ I think you'll have the same issue with those Johnson Controls controllers as well, unless they're using PID logic rather than simple on/off. I don't think they're PID controllers.



I think the issue is probably where the probe is.



OP: the probe is dangling in air inside the chamber? It's not in any liquid or insulated in any way? What's happening is when the probe reads the correct temperature (your setpoint) it turns off the fridge. But the air that is closer to the coils is going to be a lot colder than the air around the probe, and after a little bit of time, the temperature will even out more, which means the air at the probe will get colder, even though the fridge is off. The air inside the fermentation chamber is going to swing a lot like this unless you install a fan to circulate air.



The better way to monitor the temperature is to try to monitor the temperature of your beer instead of the temperature of the air around the beer, as the huge amount of liquid is going to buffer out the temp swings more, and change temperature a lot less than the air around it does. What I do is tape the probe to the side of my fermenter with a pretty thick (probably 1.5 inches) layer of bubble wrap and packing foam on top of it. Tape it up nicely so air cant freely circulate around the probe, and you should be measuring the temperature of the outside of your fermenter, which should only vary by a couple degrees from the center (warmest) part of the beer.



*edit*



I keep my probe on the fermenter as described above, but I also like to use another probe to monitor the air temp inside the chamber, mostly for ****s 'n giggles. On a cooling cycle, I have seen the air drop to the 30's, yet the beer stays right around my setpoint. That much liquid is slow to change temperature and won't match the air temp at all. So don't worry much about the air temp.

I'm sorry. I forgot to specify that I tape it to the side of my fermenter as well. It is a stainless steel fermenter so I expect it to be quite accurate.



Sent from my iPhone using Home Brew

 

[rodwha]

Indeed it is just dangling at the moment.

I did go ahead and reset it to 74*F instead. Nothing in it for now anyway, but that's not a bad temp for a pale using US-05 anyway.