Mechanical timers are more common and usually activate a defrost cycle every 8-10 hours of compressor run time. This normally occurs about once every day or two. The defrost cycle will normally terminate after 20 to 30 minutes and the compressor and fans will start again.Click to see full answer. Beside this, how often should a refrigerator cycle on and off?The refrigerator compressor should cycle four or five times a day depending on how often the refrigerator door is opened each day. If it seems to cycle too often try cleaning the coil on the back of the refrigerator. Dirt and grime on the coil will cause the compressor to cycle on and off more often.Also Know, should a refrigerator run all the time? If the coils are significantly dirty, the refrigerator will run constantly in an effort to cool down. Your refrigerator’s condenser coils should be cleaned twice a year. If the freezer temperature is above 10 degrees Fahrenheit (-12C), the refrigerator will not be cold enough. Hereof, how long should a refrigerator run between cycles? Refrigerator is new and Energy Star rated: It’s normal for a brand new refrigerator to run longer on initial startup to allow the temperature to stabilize which usually takes up to 24 hours.Why does my refrigerator turn on and off?This noise is typically caused when the fridge enters the defrost cycle and the compressor shuts off. The compressor is under load at that point and will come to an abrupt stop that causes the motor to vibrate momentarily as it powers down.