Arrived to multiple communication faults Removed both thermostats and checked for presence of ferrite rings on thermostat wires. Both thermostats were missing ferrite rings. Installed ferrite ring on main floor thermostat. Re-mounted both thermostats, ensuring both were properly seated and secure to the mounting bracket Re-wired all low-voltage control wires utilizing pigtails with wire nuts Tested system, main floor thermostat is utilizing version 04 software, will contact Rheem to confirm proper software version. System was tested in fan mode, heat mode and cool mode. System was operated from both thermostats and phone app. System was forced into each mode multiple times. System functioned as designed with no fault reported in Need to confirm software and add ferrite ring to downstairs thermostat