York LX Series HVAC System Error Codes
Severity breakdown: 6 critical , 4 warning
Error Codes
| Code | Description | Severity |
|---|---|---|
| AF | Low Flame Current | Critical |
| R1 | Flame Without Call | Critical |
| R5 | Rollout Switch Open | Critical |
| R6 | Gas Valve Failure | Critical |
| R7 | Ignition Lockout | Critical |
| R9 | Reversed Polarity | Critical |
| A4 | Improper Thermostat Wiring | Warning |
| R2 | Pressure Switch Stuck Closed | Warning |
| R3 | Pressure Switch Stuck Open | Warning |
| R4 | High Limit Switch Open | Warning |