2 red flashes / green ON
Y2 present without Y1 (thermostat or field-wiring staging error)
This code typically points to
- Thermostat staging wiring error
- Field-wiring staging error
Next checks to confirm
- Verify thermostat outputs
- Verify staging wiring
Escalation
Staging configuration issue.
Reset behavior
Soft-lockout-style reset; two occurrences do not create hard lockout.
Service Soon
Schedule repair