Can you calibrate a Johnson controller?

[TimCA]

I recently found the my 18 month old Johnson controller is off by as much as 3 to 5 F. Is there a way to adjust them? I am using a digital lab thermometer as my reference.

Thanks
Tim

[josephus]

you said Johnson

[Sven]

You're talking about the digital model correct?

A419's have an offset (OFS in the menu I believe). Use that for your adjustments.

[Speyedr]

I thought the Johnson Controller was the Analog one. If that's the case, I have the same one, and they wouldn't be very accurate to begin with I would think, since they are analog and the graduation of the dial is not very precise. I'd just set the approximate temp and then use the digital to dial it in. If you are keeping one or a few standard temps, just mark the dial once you have it right. If you want a more precise controller you probably have to go digital like the Rancos models.

[rich]

I have an analog Johnson controller and I check it frequently with a 32oz cup of water left in the ridge overnight. It's never off by more that one degree.

[Bugeater]

I have the analog Johnson controller too (2 actually). I use a cheap digital indoor/outdoor thermometer to monitor the temperature.

Wayne
Bugeater Brewing Company