Hello

For the TRANE ECGCE 205 water chiller, made in 1994, , Module B is not recognized by the main (A) cotroller following the HRD4 error on the lcd display. For this reason only Circuit A is running. B circuit does not operate despte the Selector position (A, A+B, B).
Is there a programming guide to reassign the B module on the main cotroller? both modules are in a very good codtion and no replacement seems to be required.
Thank you in advance.