Error 202 — Communication error between indoor and outdoor units (Communication error on all indoor unit, outdoor unit communication cable error)

What does 202 mean?

A system-wide communication failure where all indoor units are unable to communicate with the outdoor unit. This strongly suggests a central issue with the outdoor unit's communication cable or main control.

• Faulty main communication cable from outdoor unit
• Incorrect wiring at the outdoor unit's communication terminal
• Outdoor unit control board issue affecting all communications
• Power supply interruption to the outdoor unit

Click steps to track your progress.

1. 1

   Turn off power to the entire HVAC system at the main circuit breaker.

2. 2

   Inspect the primary communication cable connecting the outdoor unit to the indoor unit network for any damage or loose connections.

3. 3

   Ensure that the wiring terminals at the outdoor unit are secure and correctly connected.

4. 4

   Restore power and observe the system. If the error continues, professional diagnostic is needed.

5. 5

   Contact a qualified HVAC technician to thoroughly check the outdoor unit's communication system.