Ruud Furnace Code 10
Soft lockout
One-hour lockout. The control has shut gas heating down for one hour after repeated failures. Code 10 alternates on the display with the code for the fault that caused it - most often 11 (failed ignition), 13 (flame lost), 14 (unexpected flame), 59 (water sensed) or 61 (blower not running). Cooling still works.
Manual wording: “ONE-HOUR LOCKOUT ... When a failed ignition has occurred four times in a row, the control enters one-hour lockout and fault codes "10" and "11" will be displayed alternately at the seven-segment display.”
Documented for: (-)97V, (-)96V, (-)801S/(-)801P
Likely causes, most common first
- Four failed ignition attempts in a row (shown with code 11)
- Flame lost five times in a row (shown with code 13)
- Unexpected flame detected (shown with code 14)
- Repeated water-sensed condition in the collector box (shown with code 59)
- Dead blower declared after the main limit stayed open more than 150 seconds (shown with code 61)
What you can safely check yourself
- Note the second code that alternates with 10 - that is the real fault.
- Check and replace a dirty air filter.
- Make sure supply and return registers are open and unblocked.
- Check the outdoor intake and exhaust pipe terminations for snow, ice, leaves or nests.
When to call a technician
Code 10 is only the lockout timer. The alternating companion code is the actual failure, and most of those (ignition, flame sensing, blower, condensate) need a technician.
A Ruud furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.
Sources
- Installation Instructions for Upflow Condensing Modulating, Communicating Gas Furnaces - (-)97V Series (92-24161-126-04) (Rheem Manufacturing Company (Ruud brand), U97V series modulating condensing gas furnace (and U98V); TABLE 18 normal operation codes, TABLE 19 fault codes, pages 94-104) · checked 2026-08-25
- Installation Instructions for 4 Position Condensing Two-Stage, Communicating Gas Furnaces - (-)96V Series (92-24161-124-08) (Rheem Manufacturing Company (Ruud brand), U96V series and (-)(-)96MDV two-stage condensing gas furnaces; TABLE 19 normal operation codes, TABLE 20 fault codes, pages 111-120) · checked 2026-08-25
- Installation Instructions for Downflow Single Stage Gas Furnaces - (-)801S / (-)801P Downflow Series (92-24161-143-03) (Rheem Manufacturing Company (Ruud brand), U801S, U801P, (-)(-)80DSS, (-)(-)80DSP 80% single-stage gas furnaces; DIAGNOSTICS AND FAULT CODES, page 34) · checked 2026-08-25