Samsung Air Conditioner Error Code 443

Samsung air conditioner error code 443 indicates that the high-side refrigerant pressure has dropped below the expected average threshold prior to a cooling restart attempt. The system monitors high-side pressure through a dedicated high pressure sensor, and when that reading falls outside the acceptable pre-start range, the unit locks out the compressor to prevent damage. This condition specifically triggers before the cooling cycle resumes, meaning the system has detected an abnormal pressure state during the standby or restart window rather than during active operation.

The two primary causes the system is designed to detect are high pressure sensor failure and refrigerant leakage. A faulty sensor may report an artificially low pressure reading even when the refrigerant charge is adequate, causing a false lockout. Refrigerant leakage, on the other hand, produces a genuinely low high-side pressure reading because the system has lost charge. Distinguishing between these two root causes requires connecting manifold gauges to measure actual system pressures and comparing those readings against the sensor output.

Because this fault prevents a cooling restart, it is a protective lockout rather than a nuisance trip. Simply resetting the unit without diagnosing the underlying cause will typically result in the error returning. A refrigerant leak also carries regulatory implications, as handling refrigerant requires EPA 608 certification in the United States. A qualified technician should perform pressure testing, sensor resistance checks, and leak detection before any refrigerant is added or components are replaced.