Rheem/Ruud furnace status codes, decoded
Applies to: Rheem and Ruud gas furnaces with 7-segment displays (older flash-code boards: consult the door label)
What this error means
Newer Rheem and Ruud furnaces show two-digit codes on a 7-segment display. Normal characters first — 0 = standby, H = heating, C = cooling, F = fan — they're status, not faults. The fault set: 10 = one-hour ignition lockout, 11 = failed ignition, 12 = weak flame, 13 = flame lost mid-cycle (all four usually trace to a dirty flame sensor, igniter, or gas supply), 22 = main limit open (airflow/filter), 26 = reversed polarity (electrician), 33 = rollout open (SAFETY), 45/55/57 = pressure-switch faults (venting/inducer/condensate), 61 = blower motor fault, 93 = control board failure (not resettable — board replacement).
Symptoms
- Two-digit code on the furnace display
- No heat or short cycling
Try this first (safe DIY steps)
- Read and record the code; check it against the normal characters first (H/C/F/0 are fine)
- 22: filter and registers before anything
- 45/55/57: exterior vent terminations and condensate drain
- 11/12/13: flame sensor cleaning is the high-percentage fix; soft reset = thermostat heat call off 30 seconds, or power switch off 30 seconds — once
- 14 (flame with valve closed) and 33 (rollout): shut down and call — gas-safety events
Safety: power off before any physical intervention. Never bypass covers or interlocks — fuser areas run hot enough to burn.
When to call a technician
Codes 14 and 33 are safety events; 61 (blower) and 93 (board) are component replacements — service.