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error Honeywell
Error Code CHECK 94
Telephone line (Telco) fault detected.
? What Causes This
Problem with telephone line connection.
✓ How to Fix It
Check that the phone line is securely connected. If the problem persists, disconnect the control from the phone wall jack. If regular phones work correctly, call for service. If regular phones also have problems, contact your telephone company.
Source: page 44 of the official manual
From the manual
This error code appears in:
Honeywell Vista-20P Security System