Fisher FSAIF-Pro-95AE2 Service Manual page 39

9.2.2 Indoor / outdoor unit's communication diagnosis and solution(E1)
Error Code
Malfunction decision
conditions
Supposed causes
Trouble shooting:
E1
Indoor unit does not receive the feedback from outdoor unit during
110 seconds and this condition happens four times continuously.
Wiring mistake
●
Indoor or outdoor PCB faulty
●
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