Rheem Furnace Error Code 57 – Meaning, Causes & Fix

What Does 57 Mean?

What Causes This Error?

• ECM inducer motor control module failed — motor not communicating with control board
• Inducer motor bearing seized or stalling under load
• Low or unstable line voltage to the inducer motor ECM module
• Loose, corroded, or damaged multi-pin wiring harness connector at the inducer motor
• Blocked flue or intake creating excessive back-pressure against the inducer
• Inducer motor overheating due to extended operation in high ambient temperatures
• Furnace control board relay or motor communication circuit failed
• Foreign object (debris, insulation) lodged in the inducer wheel causing stall

How to Fix 57

1. 1

   Power cycle the furnace. Turn the furnace off at the power switch. Wait 60 seconds. Power back on. An ECM motor fault can sometimes be a transient communication error that clears on reinitialization. On a Rheem EcoNet-connected system, also clear the error code on the thermostat: navigate to System > Diagnostics > Clear Faults. Initiate a new heat call and observe whether the inducer starts normally and the furnace progresses through the startup sequence.

2. 2

   Listen to the inducer on startup. With the furnace powered on and a heat call active, stand near the furnace and listen during the first 30–60 seconds. The inducer should start and build to a steady, smooth-running sound within 15–20 seconds. If you hear the inducer attempt to start, stutter, or make a grinding or buzzing sound before stopping, this confirms a mechanical or electrical motor fault. If there is no sound at all from the inducer, the motor, its power supply, or the wiring connection has failed.

3. 3

   Inspect the inducer motor wiring harness. With the furnace powered off, open the cabinet and locate the inducer motor — a cylindrical motor mounted on the side of the inducer housing at the top of the furnace heat exchanger section. Trace the multi-pin wiring harness from the motor to the control board. Check each connector for: loose fit (connectors should click firmly into place), corrosion (green or white oxidation on pins), and physical damage (burned insulation, broken pins). Reconnect any loose connectors firmly.

4. 4

   Check the inducer wheel for obstructions. With the furnace powered off, locate the inducer housing (the scroll-shaped housing the motor attaches to). If accessible, carefully check for debris, insulation fragments, or foreign objects inside the wheel housing that could cause the impeller to jam. A small fragment of insulation from nearby ductwork is a common cause of inducer stalls on Rheem furnaces installed in attics or unconditioned spaces.

5. 5

   Check line voltage at the furnace. Use a multimeter to verify that the furnace is receiving 115–125V AC at the furnace power switch. Low voltage (below 105V) can cause ECM motors to fault and report communication errors. If voltage is consistently low, contact an electrician to address the supply circuit.

6. 6

   Verify flue and intake are clear. A blocked flue creates excessive back-pressure against the inducer, which can cause it to overload and stall. Inspect the PVC exhaust and intake pipes outside the building and clear any obstructions. On Rheem two-stage and modulating furnaces, the inducer modulates its speed based on the heating stage — a partial blockage may only cause error 57 on high-fire calls.

When to Call a Professional

Can You Still Use the Device?

The Rheem furnace will not attempt ignition while error code 57 is active because safe inducer operation has not been confirmed. Do not attempt to bypass the inducer safety circuit. Operating a furnace without a functioning inducer is a carbon monoxide hazard. Resolve the fault before resuming heat.