Calvin October 27, 2011 for Model Number MFC23M4BW0 My start relay went out. I ordered a new relay part# 216008900(AP2112343) and a new capacitor-run part#216985001(AP4358439). Did I need to order a new Overload Protector also? How I can I tell if it is still good?
1 Answer Hi Calvin. The relay starts the compressor for operation. The relay WR07X26749 has a coil in it that is connected in series with the "run" winding in the compressor. When the power is applied, the compressor draws a high current as it is in a "stalled" state. This current is high enough to "pull" the relay in, which connects the "start" winding. This is connected through the capacitor which gives the start winding a "leading" state in electrical terms, which sets the motor rotating. As the motor speeds up, the current drops and is no longer sufficient to hold the relay up, and the motor continues to run without the "start" winding.. The neutral, or cold side of the motor is connected via a small thermal breaker which cuts the motor off if it doesn't start, until the breaker cools down, then it has another go at starting. This is the buzz and "Click" noise you sometimes hear if you turn your fridge off for a short period and then back on. The compressor often wont start if the discharge pressure is too much greater than the suction. Some compressors have a "run" capacitor as well which remains connected to give the motor a higher torque, both for starting and running states. All of this only takes a split second. The overload is part # 216100108. Thank You. Read More...