Temp Control

[mexicanham]

Anyone have a Johnson Controls digital temp controller? I'm having trouble maintaining consistent temp. I want to maintain +/- 0 degrees variance in fermentation temp using a thermwrap. Something to do with factory settings? Differential?

[BDawg]

My A419 only goes down to a differential of 1 degree. That's still good enough, though. 0 will kill your compressor or heater.

HTH-

[BeerPal]

You probably shouldn't use less than 4 degrees differential. Anything less will cause your fridge or freezer to cycle excessively, wearing out the compressor prematurely.

[mexicanham]

Thanks guys. Not too concerned about the thermwrap...think I'll go to 1 dif. BeerPal answered my next question about refrigeration. The instructions that come with the A419 just aren't that great for us non-electrical engineers.

[BDawg]

there's great instructions for wiring up the A419 here:

http://www.zymico.com/thermostat.shtml


HTH-

[mexicanham]

Thanks BDawg. I'm mostly trying to get a handle on contolling a fermwrap heater without getting a lot of fluctuation. I think I just need to change the differential to 1 from the factory setting of 5.

This info will help, though since I'm picking up a chest freezer pretty soon.

[jamilz]

If you're using a differential of 1F, just make sure you're measuring the temperature of the beer, not the air. If you try to control the air temp to 1F you will vastly shorten the life of your freezer. If you control the temp of the beer, then it won't fast cycle and everything will be OK.

[mexicanham]

Thanks JZ. I've got the temp probe stuck to the side of the carboy and insulated from the ambient air with some bubble wrap. I think I recall you mentioning on one of your shows that the temp variance from the outside wall of the carboy to the center was slight. Seemed like the easy thing to do. I like easy. Thanks again.