Rheem furnace error codes
This chart covers the two-digit display on Rheem R801SA / 801S downflow single-stage 80% furnaces, as documented in installation manual 92-24161-143-14. Each digit shows for one second, followed by a half-second blank, so 33 reads as a three and then a three, not as counted flashes. A code records what the control observed. It does not name a failed part. Several codes lead to lockout, and some, including 14 and 33, mean the furnace should stay off until a technician investigates.
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How to read the 801S downflow display
The control shows numbers on a seven-segment display, not blink counts. 0 is standby, C is compressor operation for cooling or heat-pump heat, H is gas heating and F is continuous fan. None of these is a fault, and H does not prove warm air is being delivered. When paired codes are shown, the top bar of the display lights for half a second between them. A separate amber flame LED is off with no flame, stays on with normal flame, flashes one to four times per second for weak flame and flashes rapidly for unexpected flame.
What this chart covers and excludes
It covers the 13 fault codes in the main table of downflow manual 92-24161-143-14 (December 2017), which also describes a PSC blower motor. Rheem's official R801SA index confirms that document's authorship and revision. The chart itself was read in an exact copy hosted on ManualsLib, not on a Rheem site, and no second numeric chart corroborates it. Upflow/horizontal, two-stage, modulating, EcoNet, 801T, 801V and older 1–5 blink controls are excluded, as are water-sensor codes 58 and 59 from generic flowcharts.
- Rheem 801S downflow single-stage control (manual 92-24161-143-14): R801SA / 801S downflow single-stage 80% furnace with PSC motor
Rheem 801S downflow fault codes (manual 143-14)
| Code or flash pattern | Meaning | Model family | Details |
|---|---|---|---|
| 10Two-digit display: 10, alternating with a reason code | One-hour lockout Code 10 means the control has entered a one-hour soft lockout. Four failed ignitions, five flame losses in one heat call, unexpected flame or a dead-blower detection can cause it, and the reason code alternates with 10. | R801SA / 801S downflow single-stage 80% furnace with PSC motor | View details |
| 11Two-digit display: 11, alternating with 10 at lockout | Failed ignition Code 11 records failed ignition. After four consecutive failed ignition attempts, the display alternates 10 and 11 and the furnace enters a one-hour lockout. | R801SA / 801S downflow single-stage 80% furnace with PSC motor | View details |
| 12Two-digit display: 12 (separate amber flame LED may flash) | Low flame signal Code 12 means the control is sensing a weak flame signal. The code reports the signal level only; it does not by itself prove the flame sensor is dirty. | R801SA / 801S downflow single-stage 80% furnace with PSC motor | View details |
| 13Two-digit display: 13, alternating with 10 at lockout | Flame lost Code 13 means the burner lit and the flame was then lost. If this happens five times in one heat call, 10 and 13 alternate and the furnace locks out for one hour. | R801SA / 801S downflow single-stage 80% furnace with PSC motor | View details |
| 14Two-digit display: 14, may alternate with 10 (amber flame LED may flash rapidly) | Unexpected flame Code 14 means the control sensed flame when none should be present. 14 and 10 can alternate, and the one-hour lockout timer starts only once the unexpected flame is no longer detected. | R801SA / 801S downflow single-stage 80% furnace with PSC motor | View details |
| 20Two-digit display: 20 | Twinning fault Code 20 reports a twinning fault: a problem with the circuit or configuration used when two furnaces are linked to operate together. It is not a burner or flame fault. | R801SA / 801S downflow single-stage 80% furnace with PSC motor | View details |
| 22Two-digit display: 22 | Main limit or HALC open Code 22 means the main limit or the HALC is open. The limit protects against excessive outlet air temperature, so the control stops burner operation while it is open. | R801SA / 801S downflow single-stage 80% furnace with PSC motor | View details |
| 26Two-digit display: 26 | Line and neutral reversed Code 26 means the control has detected reversed line and neutral polarity on the furnace's power supply. Correct polarity matters because it can affect flame sensing. | R801SA / 801S downflow single-stage 80% furnace with PSC motor | View details |
| 33Two-digit display: 33 | Rollout limit open Code 33 means a manual-reset limit control, such as a flame-rollout switch, is open. A technician must identify which device opened and why before the furnace runs again. | R801SA / 801S downflow single-stage 80% furnace with PSC motor | View details |
| 55Two-digit display: 55 | Pressure switch closed Code 55 means the pressure switch circuit reads closed when the control expects it open. The contacts must be open before the next heating cycle can begin. | R801SA / 801S downflow single-stage 80% furnace with PSC motor | View details |
| 57Two-digit display: 57 | Pressure switch open Code 57 means the pressure switch stayed open when the control expected it closed. If it does not close within the 60-second proving period, the furnace enters a five-minute soft lockout. | R801SA / 801S downflow single-stage 80% furnace with PSC motor | View details |
| 61Two-digit display: 61, may alternate with 10 or 22 | Blower unable to run Code 61 means the control has inferred a dead blower because the main limit stayed open for more than 150 seconds. It is a deduction from the limit circuit, not a direct motor test. | R801SA / 801S downflow single-stage 80% furnace with PSC motor | View details |
| 93Two-digit display: 93 | Internal control fault Code 93 is a hard lockout for an internal control fault, which can include abnormal voltage persisting at the gas-valve contacts. Cycling the thermostat heat call does not clear it. | R801SA / 801S downflow single-stage 80% furnace with PSC motor | View details |
| 0Single-digit display: 0 | Standby 0 is the normal standby display. The control is powered and waiting for a call from the thermostat; it does not indicate a fault. | R801SA / 801S downflow single-stage 80% furnace with PSC motor | View details |
| CSingle-character display: C | Compressor running C means the compressor is running for cooling or heat-pump heating. It is a normal operating display on this control, not a fault. | R801SA / 801S downflow single-stage 80% furnace with PSC motor | View details |
| HSingle-character display: H | Gas heat on H means the control is running a gas heating call. It shows the operating mode only and does not by itself confirm that the burner lit or warm air is reaching the rooms. | R801SA / 801S downflow single-stage 80% furnace with PSC motor | View details |
| FSingle-character display: F | Continuous fan F means the continuous fan is on. The blower runs without a heating or cooling call, so register air will be close to room temperature. | R801SA / 801S downflow single-stage 80% furnace with PSC motor | View details |
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