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Hvac Service Manuals & Error Codes
Service manuals, error codes, and parts diagrams for hvac repair across all major brands.
528Manuals
147Error Codes
18Brands
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- Step-by-step tests with expected resistance, voltage, and continuity values
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- Verified part numbers when replacement is required
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Top Error Codes for Hvac Repair
CodeBrandDescription
1LGPCB sees IDU pipe or air thermistor as open or shorted (varies by...10LGLS902HPV/LS122HPV/LA09xHV/LA12xHV: PCB sees ODU discharge pipe...12LGPCB sees IDU middle pipe thermistor as open or shorted.13LGReactor or electronic noise filter failure in ODU.14LGCompressor Phase Amperage Error.2LGPCB sees ODU or IDU thermistor(s) as open or shorted (varies by unit...21LGInverter compressor high amperage.22LGInverter unit high amperage.23LGInverter DC link voltage too low.24LGHigh or low pressure switch open (low opens at 14 PSI, high at 600...25LGLow voltage or high voltage feeding unit.26LGInverter compressor seized, not rotating or not proving rotation.27LGInverter compressor amperage over 100A for a split second.28LGInverter DC link voltage too low.29LGInverter compressor high amperage.Popular Brands
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Access 528 service manuals, 147 error codes, and step-by-step diagnostics for hvac repair.
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