True Refrigerator Temperature Controller Possible?

I have two true commercial fridges using that same temp controller. They've been working great for the past three years. Get the temp controller, you'll be fine. I'd be more concerned about maintaining your fridge depending on how old it is. Mine were both used when I purchased them. Make sure you pop that front grill out (front, bottom) and clean the dust out of the condenser fins (they look like radiator fins). Use a metal brush or air canister and vacuum cleaner to dislodge the dust that might be preventing air flow, and be careful not to damage or bend the fins. You can prevent most cooling and sustained temp problems just by this maintenance alone, but if those fins stay dirty, there's a whole domino effect of problems that can occur.

 

Mine go in through the top left of the left side sliding door. You could drill a hole through the side of your fridge and slide the probe through there, I just didn't do it because if I ever had to sell one of them someday a potential buyer would probably just use the tiny hole as a bargaining chip to drop the price by 100 bucks. If you want to prevent your fridge from cycling too often even with the 10 degree threshold; fill an empty 12oz bottle with water, get a small bottle cork (from Home Depot or Lowes) and drill a hole big enough to fit the probe through, put a finger cot over the probe, and push it through the cork into the water in the bottle. It'll give you a true reading of the liquid temp (as opposed to the fridge's internal air temp, which changes quickly every time you open the doors) and prevent the fridge from cycling so often. That'll save you on energy consumption, potential service and/or maintenance costs, and prolong the life of your compressor and condensor.

 

10 degree differential huh? How often does it cycle?

 

Mine is in the garage, the cycle frequency varies from season to season. This time of year, when its consistently in the mid to upper 90's outside, it can cycle as much as every 20-30mins if the probe is just reading the coolers internal air temp. After I switched to having the probe read the liquid temp, it cycles much less frequently, maybe every 50-60mins or sometimes longer. I've actually noticed a difference in my monthly electric bill. The problem with these glass door merchandisers are they're not as efficient at maintaining temp like their reach-in fridge counterparts (thin glass windows vs. doors as thick as the fridge walls) but they're much cooler looking for sure.

 

Gotcha. I've got mine set at a 3 degree differential in a 17 cubic feet freezerless fridge in the basement. The cycle time is probably around 25 min or so when the basement is at 70 degrees.

 

I too have the JC A419 on a chest freezer. I have the probe going into a small playdough container filled with distilled water. I used silicone caulk to hold the probe in the hole i had drilled into the lid. That really helped me stabilize my temperature. I would advise you to tape the probe line to the fridge where ever it goes in especially important if you are using a freezer. I've read stories of guys who took the probe out to rearrange bottles, then forgot to put it back in. It warms up and then tells the cooler to run constantly resulting in frozen bottles.