What is causing my sub zero moled 590 , made in feb 93 to gradually warm up?

Hi fridges will warm up on the outside as they remove heat from the inside. excessive heat with not extreme cooling inside the fridge indicates a possible degridation of coolant fluid or a leak. as the motor tries to cool the fridge the thermostat inside stays on as the tempreture inside has not been reached. if you hear the motor/ pump continually running this will indicate a cooling problem.

MOST LIKELY FRIDGE SECTION IS LOW ON FREON! "VACUUM CONDENSER" WILL COME ON IF COMPRESSOR RUNS MORE THAN IT SHOULD BE. COMMON THING IS LEAKING EVAPORATOR COILS IN FRESH FOOD SECTION. CHECK MY VIDEO, I HOPE IT HELPS.

Hi,
The freezer coils are iced up and that is blocking the sir flow to the fridge.... You have a defrost problem and that is causing the refrigerator to be warm...

Check out these tips...they can help you figure out what is going wrong withyour refrigerator and why it is not cooling

Refrigerator not Cooling or Fridge not Cooling

How to Defrost Refrigerator Defrost Timer Problem

Water Running in refrigerator from Freezer

Refrigerator or Freezer not Cooling or Getting Cold
heatman101

Ignore the fan operation... That is perfect.

You are likely experiencing a DEFROST failure
(most commonly a defrost timer failure)...
part number 3081180 item 69 on your exploded
top view (top right side as viewed from the front).

There are typically only three (3) elements to a DEFROST
circuit:
- Defrost Timer (as noted above)

- Heater element to WARM the EVAPORATOR

- DEFROST thermostat... inhibit excess heat
(closed circuit at freezing - Opens at room temperature)

Check your defrost pan...
there should be water there DAILY...

IF not: you are assured that your DEFROST fails.

Per YOUR DESCRIPTION...
You need to look for a SUDDEN REASON (huge air leak)
why FROST would form so quickly...
USUALLY a big pizza box... BUT ANYTHING blocking a
TIGHT DOOR SEAL will cause massive frosting.

It is taking moisture from the WARM ROOM AIR and blocking your evaporator...

Yes ... all INTERIOR panels must be in place for the refrigerator to function properly.

guaranteedparts.com http://www.guaranteedparts.com/picture_library/Subzero/Subzero-500%20Series/590.pdf

Sears
http://www.searspartsdirect.com/refrigerator-repair/symptom/REF0003.html

Carnac the Magnificent

the evaporator coil inside the freezer compartment is iced over and can't transfer cold air in thes condition,remove panel inside freezer on back side of freezer compartment and thaw it out with a hair dryer,then check the defrost heating element for continuity,if its open replace it,if its good, ,check the defrost control that powers the defrost heater

Buttom freezer Sub Zero. Replacing evaporator for fresh food section.

find where line comes out under fridge in pan and blow back through line with shop air. clean evap pan inside freezer by defrosting and cleaning pan.

This is a Sub Zero and many technicians do not realize that these units most all run on 2 separate systems. 2 cold controls 2 compressors 2 evaporators. They share a condenser and condenser fan motor. What you are describing is most likely a bad cold control. It is pretty common for these to get some age and go bad. If you are very savvy with repairs yourself then if you access the compressor area and feel that the compressor on the right is cool and the compressor on the left is warm then you know that the ref. compressor has not been running. UNPLUG THE UNIT OR CUT THE BREAKER OFF. Remove the shelving from the fresh food section and the cover to the lights and the panel below the lights and lean the back panel forward to access the cold control. You will see 3 wires to the cold control. The green wire is the ground wire of corse. Unplug the other 2 wires remembering their location on the control unit. Take a jumper wire and jump these 2 wires. If when you power the unit up the right side compressor comes on then you know that your fresh food cold control is bad. Replace fresh food cold control.

The solution posted previously is TOTALLY WRONG. A Sub Zero ref doesn't have a heating element in the fresh food section. Only in the Frozen food section. It has 2 totally separate systems for each section. 2 Compressors and 2 evaporators. They share a condenser. If you are having ice build up in the refrigerator then the problem you are having is a refrigerant leak in the fresh food evaporator. You need to have a certified tech come out and replace the evaporator in your refrigerator section of your Sub Zero. Not sure what you are asking about the thermostat.

It´s probably overloaded. Any refrigerator has a specific cooling capacity eg x Kg/24hours. you must check that capacity and charge acording to that.