So, my fridge was working great, then I put a basic Johnson Controls temp controller on it, set it to 60*, put some fermenting beer in it, and left it. Beer fermented, attenuated well, no major flaws. Then I set it to cool down so I could convert it to a keg fridge. That’s when I ran into trouble since it won’t go below 54* no matter what.
So, am I hosed and need a new fridge or do you have any idea what I can do?
Would the fridge normally go into the high 30’s low 40’s and stay there? If it was working great then it should have been.
Anyway, is the fridge’s thermostat turned all the way down? And how about the temps without the controller? Could be any number of things, but check and see if it is iced up.
Just to reinforce what Euge said - make sure the fridge controls are set to max cold settings (if it has separate controls for the cooler section and freezer section set them both to max cold temp).
Like euge suggested, see if the fridge cools without the temperature controller. If it does, make sure your temp probe is not in a cold spot (on a refridgerant coil or in front of a vent fan).
Many compressors today have a timer built into them, to prevent short cycling, often 5 minutes or more before it will allow the compressor to start again. As others have said, test it with the external control removed to check the baseline operation, this will help determine where your problem is. What brand/model of fridge is it?
I took it off the temp controller about a week ago and set it to the middle setting on the fridge. I even tried lowering it to the coldest setting with the temp control off. It was at the coldest setting while fermenting. I just checked for ice and couldn’t find anything but I did notice that the freezer is at the right temp. As for how it worked before, it was down to about 36* without the controller. It’s a Kenmore model 70282991 over/under that I got from a friend in exchange for some guitar lessons. Not sure if it short-cycling but that could have happened with my analogue control.
Another thing I thought might help is cleaning off the coils this weekend.
To check for ice you might have to pull the interior panel out of the back of the freezer compartment. Usually held by a few screws. This exposes the coils which the cold air is generated before being blown into the refrigerator compartment. That’s my experience with modern refrigerators and when ice forms in there blocking air-flow the freezer compartment stays cold while the fridge portion will warm up into the 60’s.
I had a fridge at work that was doing that (fridge warm, freezer frozen). Two causes - usually it was ice buildup on the coils. Once it was the circulator fan motor - I don’t think this was an expensive fix. The way it works is the coil cool the freezer and the fan circulates cold air to the fridge through vents as needed. So if the vents are blocked or fan doesn’t work, the fridge gets warm.
I just pulled off the inside back cover and looked. No ice but the fan was not working. When I flicked the fan housing it started up and I was getting cold air in the fridge. I’ll update on whether that continues working.
I work on appliances for a living, and I’d suggest if you plan on putting anything into the fridge that is worth something to you, to replace that fan ASAP. You didn’t mention if you had planned on doing that or have done it, but it is an inexpensive repair, I do it all the time, and if it failed once, it will again, most likely sooner than later. You can easily find the part online, though the model number doesn’t look quite right, Kenmore units usually have 3 numbers, a dot, then a bunch more numbers. The 3 numbers before the dot indicate who made it for them (Whirlpool, Amana, etc), and you’ll need them to look up the correct part number for the fan.
Once you get it, search for an evap fan motor. Not expensive, easy to replace, and it will keep your product at the right temp. One important thing to look at once the cover is off and the fridge is running is the frost pattern on the evap. It should cover the whole evap top to bottom evenly. It’s easiest to see if you start with a warm freezer, and with the cover off and the fan not blowing, watch as the frost starts forming on the evaporator, it should cover it completely within 3-5 minutes or so, top to bottom. If not, there may be a sealed system issue such as low refrigerant due to a leak. Best of luck!