When I arrived I found that the outdoor unit for the 3 zone system was not operating. There were no visible fault codes on the condenser. I then reset the system and it came on. I checked the operation of the system and found it cooling properly. When I connected to the indoor u it it stated. There had been several communication faults but did not say a date. I let the client know if this keeps happening we will have to replace the wire from the indoor to the outdoor and place in conduit because it is a communicating system. I also recommend maintenance for all 3 systems.