Why does my suction pressure fluctuate?

Probable Cause: Improper remote bulb location or installation. “Flood-back” of liquid refrigerant caused by poorly designed liquid distribution device, or uneven evaporator loading. External equalizer lines tapped at a common point although there is more than one expansion valve on the same system.Click to see full answer. Just so, what causes suction pressure to fluctuate?Pressure fluctuations may occur due to inadequate storage or because the system pressure is at or near the lowest level of the compressor pressure control band. A term used to describe the pressure of a refrigerant gas at the intake point of a refrigerator or air conditioner compressor.Additionally, what causes superheat to fluctuate? Superheat hunting is a cyclical fluctuation in suction superheat due to a varying refrigerant flow rate in the system. Superheat hunting is the result of the expansion valve (see TEV illustration below) excessively opening and closing in an attempt to maintain a constant operating condition. Besides, what causes high suction pressure and normal head pressure? When the compressor rings are worn, high-side discharge gases will leak through them during the compression stroke, giving the system a lower head pressure. Because discharge gases have leaked through the rings and into the crankcase, suction pressure will also be higher than normal.What causes low suction and low head pressure?Refrigerant Pressure Diagnosis: Causes of Low Head Pressure in HVACR Systems. Low head pressure may occur simulataneously with high pressure on the suction side of an air conditioner, heat pump or refrigeration system compressor system. Refrigerant under-charge, due to a refrigerant leak or improper charge.