Johnson ControlsA419ABC-1C Electronic Temp Controller

This product was exactly what I needed. I purchased a chest freezer to convert into a kegerator (technically a "keezer") for homebrew - obviously freezers are meant to be used at temps below freezing, and I need to chill my homebrew to about 40*F, so a temp controller is required. I had never wired anything electronic before, but this was very simple and easy to accomplish. Overall, it was worth buying this unwired unit for cheaper, as I was able to wire it and install it myself for less $ than the pre-wired units from homebrew shops. If you have some steady hands, all the wires/tools required (you'll need pigtail wires, a spare 16 gauge extension cord cut in half, wire strippers, and some wire nuts) and a little bit of patience, it's worth it to purchase this unwired unit. The controller itself works great with my chest freezer - it's very simple to set up, and I'm able to achieve great temperature control for both chilling beer and maintaining specific fermentation temperatures. Highly recommended for fellow homebrewers looking to control their fermentation temps or trying to build a keezer.

Sous vide is a cooking technology that has come into popular use within the past decade. It might also be described as a fresh food preservation technique. My family really needed this, as it allows my teenage sons to cook for themselves with lower cost, less wastage, and better flavor and health prospects than they can get from fast foods.I combined the Johnson Controls A419 with an aquarium air stone to turn a simple 7 qt. Crockpot into a circulating water bath cooker that compares well with home sous vide controllers that are priced between $350 and $500.I combined the Johnson Controls A419 with a water heater element ($6 on EBay) and the air stone to turn a 28 qt. Coleman cooler into a high capacity sous vide cooker that can easily precook 100 entrees per day.The A419 relay output has been durable for me under heavy loads that are rumored online to do damage to the typical PID controller. The 1 degree F hysteresis of the A419 sounds like trouble to PID controller users who fool themselves into believing their water baths are accurate to 0.1 degrees, but it turns out that only the average temperature matters, as demonstrated by the excellent flavors of the prepared meats.

There are several models in the A419 series. I needed a waterproof version, but due to Amazon's poor product description I initially purchased another model. I had to break the tape to determine that fact, so I was charged a 20% restocking fee. Amazon should do much better.

Works as advertised. Instructions were clear. Functions for both heating and cooling; however, that has be be manually selected by using a jumper on the circuit board.

I struggled to give this unit a 5 star rating, but in the end it is an industrial grade temp controller that is sold without wires because of the multiple applications the unit can perform all requiring different wiring schemes. I am using to manage a kegerator. I read some of the reviews here on Amazon before purchasing, and most described the wiring diagram as simple and easy. I managed hooking it up correctly but it took some time and concentration. One pit-fall I could see happening to someone is the use of a ground (don't use a 2 wire lamp cord) use a 3 wire cord. The wiring diagram doesn't show any ground wires. Your fridge must be grounded so I connected the grounds inside the unit but I didn't see anyway to bond the unit to ground. Another helpful hint, you need to cut a small jumper wire to go from the line side terminal block to load terminal block. I hope this doesn't scare anyone off from buying this unit because once it is setup it has some great options for controlling heat or cooling and the LCD display adds a level of comfort that things are working as they should. There is also an LED light that indicates when there is power going to what ever you are controlling.I was also concerned about the units memory and set points in the event of a loss of power. I tested this and the unit does not lose the settings, I left it unplugged for ~24 hours and it picked right back up with no settings lost.After installing all the wires I hooked it up to a drop light in the garage, stuck the thermostat probe in the freezer just on the off chance I had screwed up the wiring, this way I'm only out a shop light not a fridge compressor.

I think the controls work great because we've gotten the same one before. I say I think because I'm not impressed at all because it didn't come with a plug in cord.

This is the best thermostat for refrigeration you can buy. I have installed more than 20 of these over the years. NOT for 24v. power supplies.......... 120 or 220v. Adjustable differential, NO or NC contacts. An adjustable short-cycle time-delay setting is available as well. You can extend the sensor up to several hundred feet using ordinary #14 wire. ON/OFF can be set to either ON at low-setting or high-setting. I have some in service that are at least 10yrs old. Buy this thermostat ! BETTER THAN THE RANCO.

This control is relatively expensive for what it does, had some problems getting "glitched" at a couple of points, and failed after a couple of years. There are other options out there for the same or better price that you can count on to be at least as reliable and last at least as long (and replace readily if they don't). I have had various temperature controllers for fish tanks and beer brewing over the past 10 years and this was the least reliable and among the most expensive.