Electric Brewing Supply 30A BCS Giveaway!

Home Brew Forums > Home Brewing Beer > Equipment/Sanitation > Johnson controller
LinkBack Thread Tools
Old 10-28-2012, 12:45 PM   #1
Bulls Beers
Feedback Score: 0 reviews
Bulls Beers's Avatar
Join Date: Sep 2007
Location: , Boston Bomber#1 place of death...
Posts: 3,067
Liked 139 Times on 104 Posts

Default Johnson controller

I just got a new chest freezer setup, but my Johnson controller seems to be 3-5 degrees off it's set point. I have another JC with my lager freezer and it's always within a degree or two. Any thoughts or am I being to anal?


Spezialisiert auf Deutsch Lagerbier...

Bulls Beers is offline
Reply With Quote Quick reply to this message
Old 10-29-2012, 07:19 PM   #2
Feedback Score: 0 reviews
Join Date: Feb 2011
Location: North Central, Ohio
Posts: 508
Liked 30 Times on 21 Posts
Likes Given: 3


If you check the temperature with an accurate thermometer and it doesn't quite agree with the JC control, I think you can adjust the offset parameter to correct for this.

Junkster is offline
Reply With Quote Quick reply to this message
Old 10-29-2012, 07:24 PM   #3
Feedback Score: 0 reviews
Join Date: Aug 2012
Location: Fort Meade
Posts: 811
Liked 46 Times on 42 Posts
Likes Given: 513


That sounds right, adjust the displayed value if it is off from the actual by a few degrees. I don't think the probes are super high accuracy.

If on the other hand you mean it is swinging the temperature too much you may need to turn down the d1f dif to 1 degree even. I would keep the short cycle delay timer as high as she goes though, or at least three minutes.

If you mean the temperature keeps dropping after the Johnson turns the freezer off, there isn't anything the Johnson can do about that, it's just on/off control, it is not tunable like a PID.

Also you might have to check the cut in/out options/settings, like is it cutting in a setpoint and cutting out at setpoint minus differential? If so it might seem like the temp is too low.

porcupine73 is offline
Reply With Quote Quick reply to this message

Quick Reply
Thread Tools

Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale - Johnson Analog controller Pogopunx82 For Sale 0 01-09-2012 01:46 PM
Johnson a419 controller hamrd DIY Projects 1 12-06-2011 12:43 PM
Johnson Temp Controller flabyboy Beginners Beer Brewing Forum 14 06-09-2011 05:47 PM
johnson controller treeak DIY Projects 6 08-28-2010 08:46 AM
getting a keg setup. Should i get a johnson controller? BeerPressure Bottling/Kegging 7 03-17-2010 01:02 AM