Home / Charts / Rheem / Ruud furnace codes

Rheem / Ruud 802P / 80MDP Furnace Codes

Applies to: Rheem / Ruud 802P / 80MDP (80% two-stage, model numbers (-)802P and (-)(-)80MDP). Seven-segment display on the furnace control.

The (-) in the model number stands for the brand prefix (Rheem or Ruud). The communicating 802V / 80MDV uses a longer code list; see its own chart.

CodeMeaningWhat to check
101 hour lockout. How to fix →
11Failed ignition. How to fix →
12Low flame sense. How to fix →
13Flame lost. How to fix →
14Unexpected flame.Gas valve leaking through or a shorted flame sense circuit. How to fix →
20Twinning fault.
22Main limit open. How to fix →
26Line and neutral reversed.Swap line and neutral.
33MRLC (manual reset limit control, also called rollout) open. How to fix →
44Low pressure switch closed. How to fix →
45Low pressure switch open, inducer on high speed. How to fix →
46Low pressure switch open, inducer on low speed. How to fix →
55High pressure switch closed. How to fix →
57High pressure switch open. How to fix →
61Blower fault: blower unable to run.

How to read the codes

Codes point to a circuit, not a part. Test before replacing anything, and never jumper a limit, rollout or pressure switch to keep a furnace running. Gas and line-voltage work is for trained technicians.

Source: Rheem Installation Instructions, (-)802P / (-)(-)80MDP upflow/horizontal two-stage gas furnaces, 92-24161-146-02, Diagnostics and Fault Codes, p. 40. The "meaning" column follows the manufacturer's wording; "what to check" is our field summary. Always go by the label on the furnace you're working on.

Related

Other brands