Your refrigerator runs all the time due to a mechanical problem. This problem could be caused by a number of issues, ranging from dirty coils to a dying compressor. The fact that the refrigerator is running all the time indicates that it is probably not cooling properly. A normally functioning refrigerator should run only a few minutes at a time for adequate cooling.
You can check for several possible causes for the refrigerator malfunction before calling a repair service. First, check to see that the door is closing all the way. It is possible that the door has somehow become jammed. If your refrigerator has an attached freezer, make sure that no obstructions are blocking the freezer vents located at the back of the freezer. Next, check the thermostat to ensure it is set at an appropriate temperature. To further troubleshoot the problem, RepairClinic suggests you pull the refrigerator out from the wall and check to see if the condenser coils are clean. Make sure that there is at least 1 inch between the coils and the wall to ensure proper air flow. If none of these problems appear to be the culprit, you need to call a repair service.