LOW CHARGE = High superheat. Low suction pressure, indoor TD, subcooling, head pressure & compressor current draw.
OVER CHARGE = Low superheat. Normal indoor TD. High suction pressure, subcooling, head pressure & compressor current draw.
LOW INDOOR AIR FLOW = Low superheat & suction pressure. Low to normal head pressure. High indoor TD. High to normal subcooling. Not much effect on current draw.
MILD LOW OUTDOOR AIR FLOW = Low superheat & subcooling. High suction & head pressure. Normal indoor TD. Normal to high current draw.
SEVERE OUTDOOR LOW AIR FLOW = High superheat, suction pressure, head pressure & current draw. Low indoor TD & subcooling.
MILD RESTRICTION (factory charge) = High superheat. Lowsuction pressure, indoor TD & current draw. Normal to high subcooling. Normal to low head pressure.
MILD RESTRICTION(with excess refrigerant)= Normal superheat, suction & indoor TD. High subcooling & head pressure. Low current draw.
SEVERE RESTRICTION(with excess refrigerant) = High superheat, subcooling, current draw & head pressure. Low suction pressure & indoor TD.
WEAK COMPRESSOR VALVES = Low superheat, current draw, head pressure & indoor TD. High suction pressure & subcooling.