Coils keep freezing up, and temperature in cooler won't go lower than 44 degrees. just installed new thermostat.

Probably... OK I am going to fill you in on something here that almost no one knows. The True coolers all use a thermostat that reads the coil temperature and has no idea what the box air temperature might be. They are all pretty much the same but have a few different variations. For most beverage coolers though they are getting the coil down to around 13-15 degrees and then shut off and stay off until the coil gets back up to 38-40 degrees.This means that the air temperature can be anywhere from 23 to 50 degrees at any given moment but the product temperature is going to average out in the middle. If the box is full no problem the temperature swing will not be anything like this because the product will keep the temperature more stable. If the box is empty you will need to put SOMETHING in there to help stabilize the temperature before panicking. 3 or 4 gallons of water will do. Also if you want to sleep better at night put a thermometer in a glass of water in the cooler to get a better idea what your product temperature really is and don't put too much faith in the cheap dial thermometer mounted to the outside of the box. Oh and set the dial on 5 and if that doesn't work the thermostat could be a problem... they are the weak link in these units.

Well, the control circuit get input from thermostat.
what you need to change is right the thermostat. I do not think there is any way to lower fridge temp if you do not replace thermostat.you could put an additional switch to turn on/off manually the compressor when you need extra cold, but in this way you risk to damage the motor.
You need to change the thermostat with one that switch on at a lower temperature. to do this you may need to use a non-fabric part.

regards

If the setting was at 80 degrees and it didn't turn off, that's because the room didn't reach 80 degrees yet. Keep track of the room temperature as well as if it turns off when set for a lower temperature.

Well, I'm not sure what your actually trying to do, but the whole purpose of a wine cooler is to cool, not to freeze and the temperature should really get no colder than 34 degrees F.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/jason_4570d45317834dd3

Many residential refrigerator / freezers are designed to work at temperature considerably above above freezing. Most modern refrigerator / freezer have a single electric thermostat - located in the fresh food compartment. This lone thermostat will control the compressor to keep the fridge (fresh food) section at the desired temperature (usually between 34 - 38 degrees F). The freezer will get colder regardless of how cold it is already whenever the fridge thermostat turns the compressor on.

Now that you see how the thermostat works, let's look at what happens when the fridge is placed in an unheated space - like a garage. In winter time, the temperature can drop considerably below 38 degrees. If the outdoor temperature remains cold enough, for long enough - it will affect the thermostat in the fridge. The temperature inside the fridge could drop below 38 degrees, preventing the thermostat from telling the compressor to turn on. Meanwhile, the temperature in the freezer compartment slowly rises from the normal -10 to 0 F degrees. It will continue to rise until it is the same temperature as the fresh food compartment or until the thermostat in the fresh food compartment tells the compressor to turn on again. This means the freezer contents will thaw.

If the temperature in the garage is even in the 40 to 50 degree range, the loss of cold in the fridge may not happen often enough to keep the compressor coming on often enough to keep some freezer items frozen solid - such as ice cream. Remember, water freezes at 32 degrees F, other products may require lower temperatures to remain frozen, and could thaw at 28 or other temperature.

Good luck!

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You have 240Volt electric water heater.
Lower thermostat is set as low as it can go at 77.
But you want water temperature set to 66?
First thing to remember is that water heater thermostat settings are approximate since they read temperatures through the steel tank wall.
Second thing is that thermostats for electric water heater are generic, and are not made for lower temperature range settings. This is probably since most people complain that water is not hot enough.
I'm looking at a generic lower thermostat from Lowes right now. The low temperature setting is 90 degrees F.
Looking at some older thermostats from a drawer right now: one does not have a lower temperature mark, the other is a Reliance with low temp of 95, the old craftmaster goes down to 80.
So I don't even have a thermostat that goes as low as the one you have, except for gas water heater thermostats that traditionally can be set to 50 degrees for vacation mode to prevent freezing.
More thermostats can be seen on following link:
http://waterheatertimer.org/How-to-adjust-temperature-on-water-heater.html

You don't note whether or not you've adjusted the thermostat. Ice cream (and juices) requires at least zero degrees, if not minus 5 degrees, for storage. Meats, fish, bread, etc. can become rock hard at much higher temperatures. Try setting the thermostat lower.

As a refrigerator, it should not go below about 34 degrees. If it is going down to 30, it may be freezing up on the coil. If you get a chance, do this: unplug the refrigerator and let it sit for 4 hours with the door open. If the coil is frozen it will defrost. You can feel the coils inside the box at the top back inside the unit. If you feel ice at any time it is an indication that it is getting too cold. Once the inside coils freeze over, the air can't flow through the coils and the unit will get warmer and warmer. When it is defrosted, set the thermostat just above the off setting. Let it run until the compressor shuts off. See what the temperature reads on a thermometer inside the cooler. If it is not cool enough move the thermostat one number colder and let it run an hour. Take your time, let it equalize before you change the thermostat. Also if the cooler is empty it is hard to set the thermostat because when you open the door all the cold air escapes and the temp will change rapidly. If it is full of cold food, opening the door won't change the temperature very quickly. Also check the radiator coils at the bottom of the cooler behind the grill. If it is clogged with dust or grease, the compressor may overheat and shut off prematurely.

When the temperature indicator flashes indicate then the temperature has ridge a level lower the the set temperature for example if you set you fridge side to 36 degree and and has fail to stop from getting cooler and has ridge 34 degree. some times those friges fail to calibrate them self tray by unplugging you dirge for 30 seconds and replug it then the board will auto calibrate for the next 24 hours If this problem comes back again that meas than your defrost element on the fridge side is bad.