Which Johnson Controls unit...

In my fermentation fridge (a chest freezer), the probe wire just runs between the lid gasket and the upper surface of the freezer body. No cutting. The gasket seals well enough around the wire.

 

Thanks guys!

 

I was wondering the same thing. I just bought a Johnson Digital Thermostat Control for my fridge and wondered if i needed to drill into the side of the fridge or just run the temp probe through the door. After reading many forums I decided I'm going through the door so I don't take a chance of hitting any coils or lines in the side of the fridge. Kinda sucks tho I just realized by turning the fridge portion into my " beer cellar " ill lose being able to use the top freezer for freezing things since the both the fridge and freezer will be hooked up to the thermostat under the same power cord. Still curious why everyone says to put the temp probe in a glass of water instead of just hanging it in the fridge. This is my first time doing this so i really don't know much about this.... Anyways good luck

 

You never adjust it? I do have to make small adjustments every now and then (never more than 2 degrees) to keep the thermometer inside at 64F. Caveat: I live in TX and the temperature fluctuations can be pretty large over the course of a year.

 

Hmmmm... Same question came up earlier today, to which I replied:
http://beeradvocate.com/community/threads/digital-temp-controller.92872/#post-1361315

The only caveat is that this may not work well if you keep the fridge set much higher than 40F.

The idea is that the glass of water will present a more stable temp, reducing the amount of cycling that will happen if you open the door frequently. My chest freezer stays closed 99.999% of the time, so it's a non-issue.

 

A thermowell is probably the best way to go but I use buckets so instead of the glass of water I tape the probe to the side of the fermenter and then cover it with either a few layers of paper towel or bubble wrap for insulation. The reading on the controler is within 1 degree of the actual temp of the wort.

When I first got my freezer and controler I wanted to test it out so if I f'ed something up I wouldn't ruin a batch of beer. I filled up a bucket with water and taped the probe to it like above. I tested the temp at different times of day/night for almost a week. It was always within 1 degree if not exact.

 

I just received my Johnson Controls Digital Thermostat Control Unit ( Part # A419ABG-3C ) from amazon yesterday. Installed it, everything seems to be going good. Not sure if anyone else has this unit or any thoughts on it. I set the temp on the unit for 51 degrees, the unit seems to be reading 48 degrees on the temp probe but the thermometer I have in the fridge reads 51 degrees. Anyone think I should be concerned with the 3 degree difference? I read the instructions that came with the unit so I believe I set everything correctly. Any feedback or info would be great. I searched for videos on YouTube and Google but couldn't find anything really helpful.

 

The more thermometers you have, the less sure you are of which one is correct. A 3 degree difference is probably enough to try and correct. To the best of your ability, try and calibrate your thermometer (ice slurry/boiling water) and see what it gives you. Checking it with another thermometer may be helpful (or you may end up with a third temp).

Do you have your thermometer in water (a 750 works great)? That really is the best way to approximate the temp of your wort before fermentation. Also, it may take hours for everything to stabilize. To be sure, give it 24 hours to settle down. Pat yourself on the back for doing your calibrating before you add the beer.

 

I did have the thermometer probe in water at first. Took it out and hung the probe in the fridge to see if it changed anything and it did slightly. Probably should have used room temp water and not bottled cold water.

 

The accuracy of the sensor on the Johnson A419 is stated to be +- 0.9 F; see this pdf document.

 

Never, but I use it for a keezer and not a fermentation chamber. I would probably check it constantly if I used it to control fermentation temps. A few degrees difference in serving temperature doesn't bug me. Also, having grown up on Pepsi and Milwaukee's Best, I probably serve my beer a little colder and more carbonated than most.

 

I usually carb my beers at the "upper limit" of priming sugar (at least in my book), about 5oz corn sugar / 5 gallons by weight, adjusted for whatever my final bottling volume is. However, temperature doesn't bother me much, I can deal with ice cold, 45F, or 55F without it really making much difference to me.

A slight fluctuation in fermentation temperature doesn't bother me, as long as I'm keeping the overall effort in the 64-66F range (primarily I'm concerned with keeping it cool and not letting fermentation temps get too high). Only if it drifts a couple of degrees higher than 66 or lower than 64 have I made any adjustments. The adjustments are small and infrequent, so I'm ok with it. Mostly the controller has kept the temperature pretty damn steady, despite not being digital and requiring occasional adjustment. I'm happy.

 

I'm trying to get a Johnson Controls A419ABG-3C to work with my freezer.

The control seems to be trying to do the right thing. It's just that after it shuts off, the interior appears to keep getting colder. Perhaps the coils are colder than the interior, the probe reads the interior, shuts off, and then the coils continue cooling the interior. The effect is certainly nothing I'd expected to see. Am I the only person who has encountered this particular problem? Would moving the probe somewhere else in the interior help? Should I deliberately raise the set point above freezing, and hope undershoot keeps it below freezing? (Which seems nuts.)

I currently have it configured like this: SP 31 degrees F, dIF 1 degree F, ASd 2 minutes.

After the compressor shuts off, it bottoms out around 26 degrees F.

 

I keep the probe stuck to the outside of my carboy with insulating bubble wrap over it. That way I'm reading the temp of my carboy (and presumably the liquid inside it) and not the air. If I'm not fermenting or lagering I just stick it to the outside of a glass bottle filled with water. That way I'm still measuring the temperature of a liquid and not the air. I pretty much use my chest freezer as cold storage when I'm not in the middle of a batch.

 

If you don't mind having a DIY project, I use a STC-1000 and I've been very pleased with the results. It is very accurate, and you can set the differential to withing 0.x degrees (I keep mine at 0.5). The unit itself is $15. The project box to house it was $5 or 8. And a few bucks for the plugs.

 

I can see that no one uses Ohmbrew

 

dear god, not for $155...

FWIW, I've seen people flash the STC-1000 with a firmware update allowing for the thing to be programmable by the hour. I don't have good solder skills, and I'm not that tech savy. But I know it's possible.

 

Why are you trying to freeze your beer? Are you making an Eisbock? : ) For cold storage/lagering I now keep mine ~ 39 with a 6*F Diff ...and most importantly an ASd of 6 min or more (unless you want shorter freezer life...ask me how I know))

 

I just realized this was a post brought back from the dead. The OP was in 2013!