Johnson Controls R SERIES Installation And Maintenance Manual page 54

E2 Freeze Protection
Freeze protection is normal protection but not abnormal malfunction. If freeze protection
occurs frequently during operation, please check if the indoor filter is dirty or if the indoor air outlet is
abnormal. The user is required to clean the filter, check the air outlet and air return pipe periodically to
ensure smooth air return and air outlet.
E3 stands for three statuses:
(1) Low pressure protection
(2) Refrigerant lacking protection
(3) Refrigerant recycling mode
1) If enter refrigerant recycling mode through special operation, the displayed E3 is not an error
code. It will be eliminated when exiting refrigerant recycling mode.
2) If you do not want to have refrigerant lacking protection, you can enter the debugging mode
through wired zone controller and then cancel the refrigerant lacking protection mode.
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