I need help with my Johnson A419!

[J2W2]

Hi,

I'm finalizing my new keezer setup. As the title says, I'm controlling the freezer with a Johnson A419. I have moved the two kegs from my kegerator into the keezer, and I have the temperature sensor attached to the side of one of the kegs.

This is a new A419, and I have not changed any of the factory settings on the jumpers, etc. I have the Setpoint set at 39 degrees, the Differential set at 5 degrees, the Anti-short Cycle Delay set to 10, and the Temperature Offset is set to 0. I have also set the Sensor Failure Operation to 0 (de-energized).

When I plugged everything in, the A419 was reading 68 degrees (room temperature), so the freezer kicked on. I attached the sensor to the side of one of the kegs with Velcro, and the A419 reading quickly dropped to 35 degrees (my kegerator has been running cold on me).

So far so good, but the A419 never turned the freezer off when the sensor reached 35. I thought by my settings that it should have turned it off as soon as it reached 39 degrees (my Setpoint). The freezer has now been running constantly for 30 minutes or so.

Do you think there is an issue with my controller, or do I have one or more settings wrong? At this rate, I'll have two frozen kegs by morning!

Thanks for the help!

 

[benco]

I would read the directions again and make sure the settings are correct. Also I have my probe in a large glass of water. You may also have to tinker with it some. Be patient. I hope that helps.

 

[J2W2]

I would read the directions again and make sure the settings are correct. Also I have my probe in a large glass of water. You may also have to tinker with it some. Be patient. I hope that helps.

I'd thought about the glass of water trick, but I figured the keg is already there, and it won't accidentally get knocked over. I initially just had the probe hanging in the freezer, but it always seemed to work its way to the side of the freezer, which is obviously the coldest part when it's running.

I'm guessing I may not understand how the differential works. I figured it was how much the temperature could rise before it kicked on again. Now I'm thinking it's how many degrees down it will cool, once it hits my set point, before it shuts off. So, having my set point at 39 and a differential of 5 probably means it kicks on at 39 (or above when I first started it up), and will run until it hits 34. It is off now, and up to 36, so I'm guessing it touched 34 and shut off for now.

I think I'll try a set point of 43, and a differential of 2, since I'm shooting for 42 degrees right now. As long as I keep the probe attached to a keg, I can't imagine it will kick on or off very quickly.

Thanks for the help!

 

[day_trippr]

There are in fact two cooling modes on the A419 - "Cooling Cut-Out" and "Cooling Cut-In".

The former works the way most of us expect a thermostat with adjustable differential would work: it cools down to Set Point, shuts off the cooler, then when the temperature drifts up to Set Point + Differential, turns on the compressor.

The latter will cool down to Set Point - Differential, shut off the compressor, then when the temperature rises to Set Point turn on the compressor.

There are jumper settings for four modes of operation. It's not inconceivable that the final assembler screwed up...

Cheers!

 

[FloppyKnockers]

I need help with my Johnson A419!

Why? Doctor told you not to lift anything too heavy?

 

[J2W2]

There are in fact two cooling modes on the A419 - "Cooling Cut-Out" and "Cooling Cut-In".

The former works the way most of us expect a thermostat with adjustable differential would work: it cools down to Set Point, shuts off the cooler, then when the temperature drifts up to Set Point + Differential, turns on the compressor.

The latter will cool down to Set Point - Differential, shut off the compressor, then when the temperature rises to Set Point turn on the compressor.

There are jumper settings for four modes of operation. It's not inconceivable that the final assembler screwed up...

Well, in reviewing the instructions again, it mentions cut-in and cut-out, exactly as you say. It also says JUMP2 controls this feature, and the factory setting is cut-in. So, I guess it's working as designed, although this does seem backward to me. No matter as long as I know, I just raised my set point to the high end, and let it cool to the low end (set point - differential) before shutting off.

Thanks again to all for the help!

 

[GurGinator28]

Hi,

I'm finalizing my new keezer setup. As the title says, I'm controlling the freezer with a Johnson A419. I have moved the two kegs from my kegerator into the keezer, and I have the temperature sensor attached to the side of one of the kegs.

This is a new A419, and I have not changed any of the factory settings on the jumpers, etc. I have the Setpoint set at 39 degrees, the Differential set at 5 degrees, the Anti-short Cycle Delay set to 10, and the Temperature Offset is set to 0. I have also set the Sensor Failure Operation to 0 (de-energized).

When I plugged everything in, the A419 was reading 68 degrees (room temperature), so the freezer kicked on. I attached the sensor to the side of one of the kegs with Velcro, and the A419 reading quickly dropped to 35 degrees (my kegerator has been running cold on me).

So far so good, but the A419 never turned the freezer off when the sensor reached 35. I thought by my settings that it should have turned it off as soon as it reached 39 degrees (my Setpoint). The freezer has now been running constantly for 30 minutes or so.

Do you think there is an issue with my controller, or do I have one or more settings wrong? At this rate, I'll have two frozen kegs by morning!

Thanks for the help!

I just got my A419 for my keezer. It came set for Cooling Cut-In. I had to change it to Cooling Cut-Out. You have to open it up and move a jumper from one pin setting to another. There was a diagram in the instructions I followed.

 

[billybryson54]

Yup. I had the same issue. If I had mine set to 40 with a 5 degree differential, then it would turn ON at 40 and OFF at 35. Minor inconvenience, I didn't bother to change it