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Error code reference
Trane HVAC Error Codes
8 error codes documented with diagnostic procedures.
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E0Main processor error on BAYSENS135* zone sensor.E1Heat failure diagnostic indicating an error in the heating system.E2Cool failure diagnostic indicating an error in the cooling system.E3Test mode indicator showing the system is operating in test mode.E4Fan failure has occurred and service is required.E6Software conversion conflict on BAYSENS135* zone sensor.E7Communication error on BAYSENS135* zone sensor.E8Temperature input outside valid operating range (32°F-122°F) on BAYSENS135* zone sensor.
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