Need help with Johnson Controls A419 Settings

[ak6143]

I just got this unit. Im curious to know how most people set this up in terms of "cut in at set point" vs "cut out at set point". In my mind I would want it set to cut out at set point, and then set the SP at my desired temp but Im just checking. With the diff, if I set it at say 4 I assume that means it will cut in if my temp climbs by 4 deg from my set point (assuming SP is in Cut out Mode). Please let me know

 

[BigB]

I have my cut in SP set as it warms up naturally.. then the cut in will turn the unit on and cool down. I have my differential set at 2 degrees though... It does not cycle too frequently either.

 

[chemman14]

I have mine cut in and set point with a differential of 1. I then set the set point 1 degree above desired fermentation temperature

 

[ak6143]

so the way yours is set up is if your SP is say 40 deg, its going to kick on at 41 deg, correct? So you change any of the other settings on there Asd, Ofs etc?
Thanks

 

[chemman14]

so the way yours is set up is if your SP is say 40 deg, its going to kick on at 41 deg, correct? So you change any of the other settings on there Asd, Ofs etc?
Thanks

no, for example right now my set point is set to 68. So when the temperature goes to 68 it kicks on when it reaches 68 until it gets to 67

 

[BigB]

no, for example right now my set point is set to 68. So when the temperature goes to 68 it kicks on when it reaches 68 until it gets to 67

Mine is this way too, except I set my SP one degree above where I want to be. So for example, if I want 50, I set it at 51. Then the unit will kick on at 51 and run until it hits 49.

 

[DSmith]

I like cut-out at setpoint because you're setting either the hottest or coolest temperature. Either way works. I installed an external switch to switch from heating and cooling and leave the internal jumper alone for cut-out at setpoint.

https://www.homebrewtalk.com/f163/belgian-tripel-trended-fermenter-temperature-330554/

Here is a thread where I've documented the actual temperature change with a 1F differential in cooling mode (probe insulated over on the outside of a carboy) showing cut-out at setpoint. I wish the differential could get smaller but at the same time the freezer isn't cycling too much and it doesn't seem to be affecting the yeast attenuation.

I also document the heating mode with the probe just in the air. The beer temperature is much more consistent this way and it's not a problem to cycle a heating pad.

 

[chemman14]

Mine is this way too, except I set my SP one degree above where I want to be. So for example, if I want 50, I set it at 51. Then the unit will kick on at 51 and run until it hits 49.

yep thats exactly how i have mine

 

[Junkster]

I've put several of these controls in commercial refrigerators and use the cut-out @ setpoint with 4 or 5 differential and the ASD usually about 5 which is usually enough time for pressures to equalize enough via the cap tube for an easy compressor restart (as observed with gauges connected). The sensor is in the return air path to the evaporator which can change rapidly. If the probe is against the fermenter or in some thermal mass, then you can get away with a smaller differential number.

 

[ak6143]

Thanks for the help. Im just using the unit to keep my fridge at the proper temp for now. Ive got it set to cut in at 42 deg with a 4 deg diff.