STC-1000 Temperature Controller

[adams81]

Temperature controller finally came in the mail!



Build went successfully following both these links:

http://community.mrbeer.com/forum/18-ad ... h-pictures" onclick="window.open(this.href);return false;

http://www.hoptomology.com/2012/02/06/h ... oller-box/" onclick="window.open(this.href);return false;

The outlet is only wired for cooling only, and the freezer I'm using it with is rated for 3 amps.

I started with the sensor placed in a water reservoir but I don't think that that accurately reflects temperature of the "freezer" as the water would take too long to change temp. Sensor is now taped to the side, which causes it to cycle more but maintain a more accurate temp.

Overall it was really easy, and I don't really have any electrical experience. The hardest part was getting that plastic cut without a jigsaw or dremel (never again). Next time I would definitely find a different housing. Total cost was around $60



Sent from my GT-I9000

[chalmers]

Glad you got it done. The reason to place the sensor in some water is to mimic the temperature of the beer vessel, which had a larger thermal mass than the sensor in the air. The temperature swings will be less pronounced.

[Cobalt]

Ahhhh, thats why the temp should be in water, im going to have to change mine to that. Also, where did you find that project box, or whatever it is? I used scrap lumber, wood trim actually lol. And its quite easy to wire it up and have the other outlet set to a heat source if you wanted to.

[adams81]

It's an electrical enclosure from home depot. Perfect size, though I'd think twice if you don't have the tools to cut thicker plastic.

I actually was going to wire the heat outlet, even though I don't have/need a heat source, but I made a stupid mistake - my marrettes were too small!

You're right, the sensor definitely needs to be in water. The compressor is running way too often!

Sent from my GT-I9000

[sleepyjamie]

i dont have mine in water and my compressor doesnt turn on very often.
i simply tape the sensor to the side of the bucket/keg and insulate around it

[bluenose]

I used the same box, and used a drill and jigsaw to cut the hole

[Jayme]

Ahhhh, thats why the temp should be in water, im going to have to change mine to that.

Taping to the side of the carboy with a good amount of insulation is better than a water reservoir.

Reason being, yeast growth gives off a fair bit of heat. The glass of water will not reflect this (arguably it will, but there's a pretty big buffer involved, meaning your beer will experience larger temp swings). Once the yeast has finished its exponential growth phase, there is not nearly as big a difference. All depends on what you're trying to accomplish really. But if it's a single fermenter in a chamber, it's best to monitor it direct.

[chalmers]

I didn't think of this option earlier, but I'm with Jayme.
Ideal is to use a thermowell down inside your carboy, second would be the probe on the outside of the carboy with insulation to closely shadow the carboy temp, next best would be in the water bottle. Not great would be just hanging there, so turning the cooling (or heating) on and off could cause large swings in temps at the probe.

[Jimmy]

Is anyone running heating AND cooling on their STC-1000? How do you keep them from fighting against each other (ie: cooling turns on but drops temp a bit too much, resulting in heat kicking in, which in turn heats too much and results in cooling turning back on). Why do I want to do both you ask? My basement is a bit cool right now for where I want to ferment my ales. I'm thinking about adding an aquarium heater to my chiller bath, and recirculating that through the jacket on the conical. If the temp rises enough in the basement, it could cause the ferm temp to get too high, so I'd like to have the chiller plugged into the STC just in case. My concern is simply the 2 modes fighting with each other and wasting a bunch of electricity

[Keith]

Set your room temp to be 1-2 degrees lower than the ferm temp. Then just use the heater.

[Jimmy]

Set your room temp to be 1-2 degrees lower than the ferm temp. Then just use the heater.

I don't turn the heat on in the basement. I can run the aquarium heater to heat it no problem, and would likely be fine with that. I just want to have the chiller on demand just in case it's required.

I'm thinking just the aquarium heater will likely be fine, though. Maybe I'll give it a try without the chiller running and see how consistant it is.

[mcgster]

Is anyone running heating AND cooling on their STC-1000? How do you keep them from fighting against each other (ie: cooling turns on but drops temp a bit too much, resulting in heat kicking in, which in turn heats too much and results in cooling turning back on). Why do I want to do both you ask? My basement is a bit cool right now for where I want to ferment my ales. I'm thinking about adding an aquarium heater to my chiller bath, and recirculating that through the jacket on the conical. If the temp rises enough in the basement, it could cause the ferm temp to get too high, so I'd like to have the chiller plugged into the STC just in case. My concern is simply the 2 modes fighting with each other and wasting a bunch of electricity

I do this with the aquarium heater in a water bath and a large fan blowing over the water surface (you would be surprised how much a fan blowing over the water will cool!)

I don't find that i am getting a cycling on and off. By adjusting your F2 value to pick your offset and your F3 to configure your cycle time i think its manageable.

Mind you i'm not TOO concerned because its just a fan... i would be more concerned i guess if it was a chiller!

[GDoucet]

Is anyone running heating AND cooling on their STC-1000? How do you keep them from fighting against each other (ie: cooling turns on but drops temp a bit too much, resulting in heat kicking in, which in turn heats too much and results in cooling turning back on). Why do I want to do both you ask? My basement is a bit cool right now for where I want to ferment my ales. I'm thinking about adding an aquarium heater to my chiller bath, and recirculating that through the jacket on the conical. If the temp rises enough in the basement, it could cause the ferm temp to get too high, so I'd like to have the chiller plugged into the STC just in case. My concern is simply the 2 modes fighting with each other and wasting a bunch of electricity

I use a mini fridge as my fermentation chamber and used a heater wrap a couple times with the carboy in the fridge during the vigorous fermentation. With the probe in a thermowell, in my case, the wort cools to 0.4 degrees below my set temp. So I set the temp offset to 0.5 degrees and that way the cooling and heating aren’t competing. This gives worst case a 1 degree swing in fermentation temp. I’m not sure how big of a swing you want but with a jacketed conical, I would think the over cooling would be less than mine depending on your set up.

[Jayme]

That's the best way to do it - figure out how much your system overshoots and set the hysteresis just a bit greater than that. If you can, play around with probe placement to see if you can get it a bit better.