⚠
warning Honeywell
Error Code System does not respond
Heating/cooling system is controlled by thermostat but is inactive after commands are given.
? What Causes This
(1) Inconsistent temperature settings vs. actual room condition or improper installation (2) Control signal interruption/blockage from thermostat to HVAC unit.
✓ How to Fix It
(1) Ensure heat/cool setting matches indoor/outdoor conditions, higher for heating below threshold temp / lower for cooling above it. (2) Power cycle both units or check physical connections/wiring.
Source: page 18 of the official manual
From the manual
This error code appears in:
Honeywell Focuspro Th6220d