Configure Johnson controler A19AAT HELP!!!!

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zman

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I have a Johnson controller model A19AAT and I am trying to configure it for a warmer temp. to ferment a brew using Heffe Yeast. I want it to ferment in the low to mid 70's. I opened it and set the set point to the highest notch. 40F. I am assuming that since I set it to 40F that is the lowest point? If not is there a way for me adjust this so that I can get the fridge to warm up to and maintain 70F??
 
It does say it is 20-80F but it does not seem to be getting above 65 in the fridge. Perhaps I just need to upgrade
 
Now I'm confused. You say the highest point is 40F, then you say it's not getting above 65F? What's your ambient temp?
 
Easiest route (also probably most expensive)? Buy a digital controller that can control a cooling or heating device. Hook up the thing to a small heater fan in your ferment chamber when its too cool to ferment ales or you want to ferment something like a hefe or saison at 72-75-77F but the ambient is too cool... it will run the fan to warm it up to that temp and shut off the heater/fan. In a fridge, it should maintain temp for quite some time so the heater probably wouldn't even need to run much.

If you don't want to buy a new temp controller, maybe just move the fermenter somewhere warmer in your house and/or use a brewbelt or something?

The analog, single stage controller isn't going to make your fridge heat, so if the ambient temp (assuming in your basement or something) is < 70F, that's what your fermenter is going to be sitting at... the analog, single stage controller is actually pointless until it gets too hot in your chamber, which doesn't appear to be the problem at all.
 
I've never had a problem getting to the high 60's and 70&#730; with that unit. You shouldn't have had to open it to adjust anything. Where are you placing the temperature probe? What is the temperature of the air outside the fridge? How are you measuring the temperature inside?

On a side note, two things I've found, through personal experience, that really help utilize the effectiveness of the unit are:
1. Plug everything in
2. Put the probe INSIDE the fridge.
 
I've never had a problem getting to the high 60's and 70&#730; with that unit. You shouldn't have had to open it to adjust anything. Where are you placing the temperature probe? What is the temperature of the air outside the fridge? How are you measuring the temperature inside?

On a side note, two things I've found, through personal experience, that really help utilize the effectiveness of the unit are:
1. Plug everything in
2. Put the probe INSIDE the fridge.

I have the temp probe mounted so that it is hanging from the interior ceiling of the fridge. The temp of the house is roughly 65F as is the temp inside the fridge. I have a waterproof thermometer inside the fridge to monitor the internal temp. Everything is plugged in and the probe is inside the fridge. I would not expect it to work if it were outside the fridge.
 
Um, a refrigerator is designed to remove heat, not create it. If your ambient is 65F, I wouldn't expect to be able to go higher than that without some kind of heat source.
 
Um, a refrigerator is designed to remove heat, not create it. If your ambient is 65F, I wouldn't expect to be able to go higher than that without some kind of heat source.

I understand the concept of refrigeration. I was just confused as to how the controller is supposed to maintain temps to 80F w/o the aid of a heating device. The instructions that I did find about this model did not explain if the controller could provide this functionality
 
It can't. This is a single stage, SPST unit meant to provide cooling. You MAY be able to modify it to provide heating, but not both at the same time.

One option I have seen is people stick a 100 watt light bulb inside the refrigerator and leave it running all of the time. Wastes quite a bit of energy, but it could work.
 
I was just confused as to how the controller is supposed to maintain temps to 80F w/o the aid of a heating device.

It will only maintain temps up to 80F if the ambient outside temp is > 80F. Unit is for cooling, not heating...

If you want to control a heater, light bulb, brew belt, whatever to warm the ambient temp from 65F to 75F (which is what you need to do) then you need to buy a digital controller than can control heating devices, as well. I think I picked mine up for < $100 shipped somewhere. I think maybe Northernbrewer?
 
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