Rheem Classic Series Error Codes — What It Means
Rheem’s Classic and Classic Plus furnaces (models R801T, R96V, R97V, R92P, and the RGFE/RGFJ series) are among the most common residential furnaces in North America. They use a blinking LED on the control board to communicate fault codes. Rheem also makes Ruud furnaces — identical hardware, identical codes. Open the lower access panel and count the LED blink sequence.
Flash Code Quick Reference
| Flashes | Meaning | Common Fix |
|---|---|---|
| 1 | Ignition lockout (retries exceeded) | Clean flame sensor; check gas |
| 2 | Low/single pressure switch open | Clean condensate trap |
| 3 | High pressure switch open (2-stage only) | Check hose and pressure switch |
| 4 | High limit device open | Replace filter; check blower |
| 5 | Roll-out switch open or flame without call | Safety issue — inspect HX |
| 6 | Inducer motor fault | Check motor RPM and wiring |
| 7 | Flame signal low | Clean flame sensor rod |
| 8 | Rollout switch circuit open | Manual reset; inspect burners |
| 9 | Reversed line voltage polarity | Rewire at disconnect |
| 57 | Abnormal operation / board fault | Check wiring; may need board |
Classic Series Model-Specific Notes
R801T (80% AFUE, single-stage): No condensate drain, so 2-flash codes always point to the inducer or pressure switch hose — never a blocked drain trap. These furnaces are simple and long-lived; most faults trace to a dirty flame sensor or weak blower capacitor.
R96V (96% AFUE, variable-speed): Has a variable-speed ECM blower motor. High-limit faults (4 flashes) on R96V often trace to low blower speed caused by high static pressure in the duct system rather than a dirty filter. Check duct static pressure if the filter is clean.
R97V (97% AFUE, 2-stage variable-speed): Two-stage gas valve means two pressure switches. A 3-flash code (high-pressure switch) can indicate the high-stage switch is stuck open. Verify both pressure switch hoses are intact — the second hose on a 2-stage inducer is easy to overlook.
Most Common Fixes {#fix}
1 Flash: Ignition Lockout
- Look through the sight glass — did the igniter glow? If yes, suspect gas supply or flame sensor.
- If the igniter glowed but no flame appeared: verify gas valve opens (listen for click), check gas pressure.
- Remove the flame sensor and clean the rod with 400-grit sandpaper.
- Power cycle and retry.
2 Flashes: Pressure Switch Open (96/97% Models)
- Locate the condensate drain trap — white plastic U-trap at the furnace base.
- Disconnect the outlet hose and pour water through to verify free flow.
- Inspect the rubber hose from the inducer to the pressure switch for cracks.
- Test the pressure switch with a vacuum pump — it should close at approximately 0.6–0.8” WC.
4 Flashes: High Limit
- Replace the filter (Rheem 1” media filters clog in 30–45 days during heavy use).
- Verify all supply and return registers are open.
- On R96V, check blower speed — the motor should accelerate smoothly to full speed.
- If the limit still trips, have a technician check static pressure and heat exchanger condition.
7 Flashes: Low Flame Signal
- Remove the flame sensor (single 1/4” hex screw).
- Rub the metal rod with fine steel wool.
- Reinstall and power cycle.
Parts Often Needed
| Part | Notes |
|---|---|
| Flame sensor | Amazon | Rheem 62-22868-92 |
| Hot-surface igniter | Amazon | Rheem 62-23543-01 |
| Condensate trap | Amazon | Rheem AP14230C |
| Pressure switch | Amazon | 0.60” or 0.80” WC, model-specific |
| Blower run capacitor | Amazon | 5–10 µF / 370V |
When to Call a Pro
Code 5 (rollout or flame without call) and code 9 (reversed polarity) require technician attention. Rollout on a Rheem Classic can indicate a cracked primary heat exchanger — CO can enter the living space through a cracked HX.
See Also
- Rheem Water Heater Error Codes — Complete Guide
- Rheem Furnace 5 Flashes Error Code — Flame Sensor Fault Fix
- Rheem Furnace 9 Flashes Error Code — Causes & Fix
- Rheem Air Handler E1 Error Code — Causes & Fix