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Bosch Air Handler Error Codes

Updated · by Aurora Star Tech Inc.

7 Bosch Air Handler error codes and diagnostic codes, with causes and troubleshooting steps for each. Select a code, or find your model below.

Homeowner with a air handler problem? Call (647) 657-2977 or book a service call — licensed technicians across Vaughan and the GTA.

Bosch Air Handler error codes list

CodeMeaningSeverity
2 flashesIndoor T2 sensor faultMedium
3 flashesRefrigerant sensor faultMedium
4 flashesRefrigerant sensor communication faultMedium
5 flashesIndoor-to-outdoor communication faultHigh
8 flashesRefrigerant sensor past service lifeLow
Continuous flashingR-454B refrigerant leak protectionCritical
LED offPower supply failureHigh

Find codes by Bosch model

BIVA20-24BIVA20-36BIVA20-48BIVA20-60

General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.

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Air Handler Emergency

647-657-2977