I have a miele KFN 8462. Why does the drainage hole in the freezer compartment, which discharges water to the outside, freeze?

The error code you are experiencing on your Miele KFN 12823 SD1 with four beeps and flashing of the super freeze LED, along with the 9 and 5 LEDs on the fridge temperature block, is indicating a problem with the fridge evaporator sensor. This sensor is responsible for monitoring the temperature inside the fridge compartment and is located in the fridge section.
According to the service manual, the evaporator sensor for your model is located inside the fridge compartment, behind the light unit and it can be accessed by removing the light cover. The sensor is connected to the main control board via a cable.
It's important to note that the location of the sensor can vary depending on the specific model. In your case, since the sensor seems not to be behind the light unit, it could be that it is foamed-in.
If you want to replace the sensor, you will need to carefully remove the foam insulation in order to access the sensor. This can be a delicate process and it's important to be careful not to damage the insulation, which can affect the cooling efficiency of the fridge.
It's recommended to have a professional technician to help you with the replacement, as it might involve handling with refrigerant and electrical connections.
It's also important to make sure that you have the correct replacement sensor for your model and to follow the instructions in the service manual to ensure a proper installation.

Press alarm button once
either left door open too long or temperature too low

adjust fridge to 4 centigrade
freezer to -17 centigrade

There is no part number for the drain. find a piece of copper tube that fits inside the hose and ease it up inside the broken drain hole but only a short way. Silicon seal around underneath it

apparently its a problem with the evaporation sensor.

If the freezer is on top then empty out the freezer and remove the bottom and back liner of the freezer compartment usually phillips screws. In the back you will see the freezer coils along with a defrost element. Below these two items u will see a drip tray that collects water from the coils on defrost cycle, in the center of the pan will be a drain hole that connects to a hose that leads to a pan under the refrigerator.Normally the water is collected there and evaporated. The hole in the tray in the freezer is clogged. Thaw it and clean it until you can pour water in it and it goes to the pan down below. please rate me

make sure you have cleared the drain all the way to the drip pan, and the fridge should be tilted slightly to the rear for good drainage........make sure there is a clear path for the water to make it to the drain hole

Freezer /fridge leaking water/ice frozen in fridge and or freezer, or leaks on floor

Usually due to CONDENSATION due to bad door seals or a plugged evaporator drain line? Can use a soft flexable tubing and very hot water to clean it out. Bad door seals usually need replacement, but u can use a blow dryer and something to pry it closer to the door wall while blowing hot air on to it. To create a seal, to test for bad door seals place a dollar bill in between the door and wall of fridge where it closes. Then slide out the dollar bill with door closed. It should offer some resistance and not be easy to pull out.

Fix any gaps in the door seal.Pack out the seal underneath the areas where the door seal has the gaps. This can be done with a small strip of weather stripping, as shown here, or a bit of tightly rolled up paper under the door seal. Alternatively, you can heat the door seal up with a hair dryer to fix the gaps. This softens the door seal and allows you to stretch it.

Most all fridges have a drain. Look inside your fridge for a "V" shaped channel with a small hole. This hole leads to a tube and a small pan which sits on top of your refrigerator's compressor. The defrost cycle causes water to run into the channel, down the tube, and then it generally evaporates with the heat of the hot condenser/compressor.
However, if that tube is clogged with food crumbs, particles , debris etc, you will have to clear it to get back to a normal mode of operation. A toothpick, pipecleaner, straw or a cotton bud can often do the trick. Another trick one can use is to connect a copper tube wire with one end going into the drain hole then attach the other end to the heater wrap it around heater a few times. That will take care of the drain problem when it comes to ice build up but not food build up.
Even a frost free freezer will still ice up at times in the areas away from the heated defrost area and the drain line can freeze. This icing causes the pipe work to the compressor to ice over or sweat and cause a puddle. Or if the drainage has frozen over, it will need to be de-iced. ( usually the line is under the freezer bottom plate covering. Towards the back of the unit) And there is another inside the fridge area also.
Give the freezer a good overnight defrost until it's totally clear of ice in addition to making sure the drain is clear to the pan at the back and then restart the freezer.
God is so good: so this is why I give free advice so please thank him not me.

OTHER THINGS TO CHECK ARE THE DEFROST TERMINATOR AND THE HEATER ELEMENT FOR COBNTINUITY.


http://www.appliancerepair.net/refrigerator-repair-1.html

https://www.youtube.com/watch?v=HHr7bCO_IiA unclog drain hole

https://www.youtube.com/watch?v=H_DKNtgd5vI


1-3 TEMPERATURE CONTROL
As the food in the fridge gets colder, it gives off less heat, and the air inside the fridge will remain colder. A thermostat called aCOLD CONTROLwill cycle the cooling system on and off to keep the temperature inside your fridge within a certain range. You can adjust that range using one of the dials within your fridge.
On most fridges, all the cold air for both the food compartment and the freezer compartment is produced in one evaporator. Since the freezer is so much colder than the food compartment, most of the cold air that is produced circulates to the freezer compartment. Only a small amount is needed in the food compartment to keep it down to the proper temperature. This amount is adjusted by a smallAIR DOORin the duct between the evaporator and the food compartment. The control for this air door is the other of the two dials within your fridge.
Check ur cold control thermostat, ur thermistors in both fridge and freezer ( they should be checked for both ohms and for amount of current being put out as per ur model ), ur air flow vent from freezer to fridge.( to make sure it opens and closes without any restrictions) On thermistors check for A close circuit and amount of ohms not just an Ohm reading. As per ur model. Most should atleast show 1200 ohms. Also Check door seals for leakage.

The likely cause is the drainage outlet is blocked by dirt deposits or frozen ice behind the plastic panel inside the freezer compartmrnt. Melted ice overflows the tray insteady of being discharged through the tray's drainage outlet tube.

To check if the tray drainage hole is blocked, it is easy to take off the plastic panel inside the freezer compartment by undoing the six small screws.

Please don't forget to switch off the electric before you attempt to clean the blockage. Good Luck