Manifold Gauge Set: Notes
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A manifold gauge set is used to determine system's high-side and low-side pressures, correct refrigerant charge, and operating efficiency. High (discharge) and low (suction) pressures must be compared to determine system operation. Manifold gauge sets for the 2 refrigerant types are basically the same except for fittings at ends of hoses. Fittings are different to ensure connection only to appropriate refrigerant system.