Amana AMVC960803BN Error Code Eb6: Over/Under Voltage Trip or Over Temperature Trip

What Does Code Eb6 Mean?

The variable-speed blower in this furnace is an ECM motor with its own onboard power module (an inverter that converts and controls the electricity driving the motor). That power module constantly watches the incoming AC line voltage and its own temperature. When either goes out of bounds, the module shuts the motor down and reports Eb6 to the Amana integrated control module, and the furnace stops circulating air.

There are three triggers behind Eb6. Line voltage that runs too high, line voltage that sags too low (a brownout, an overloaded shared circuit, or a weak service connection), or an over-temperature trip on the power module itself — which can come from high ambient temperatures around the furnace, blocked clearances, or a failing module. If the voltage disturbance is brief, the motor may restart on its own once conditions return to normal; if it keeps recurring, something in the power supply or the motor needs attention.

Eb6 is a power-and-heat protection code, which sets it apart from the other blower faults on this board. It is not a jammed wheel (that is Eb5, locked rotor) and it is not a load-driven overcurrent from a blockage (that is Eb4, current trip). Because Eb6 is fundamentally about the quality of the electrical supply, it is closely related to this furnace's line-supply integrity codes: EEA (reversed line polarity, where hot and neutral are swapped) and E10 (grounding fault, a poor or lost neutral connection). A supply problem serious enough to show up as EEA or E10 can also stress the motor's power module.

What You'll Notice

• The blower runs, then cuts out unexpectedly during a heating cycle
• The furnace shuts down and restarts on its own when line conditions recover
• Blower shutdowns that seem to line up with other large appliances cycling on
• Reduced or intermittent heat because the blower will not stay running
• The motor or blower housing feels unusually hot to the touch

Common Causes

How This Is Diagnosed

A technician measures the line voltage at the furnace disconnect and compares it against the range printed on the furnace rating plate, watching for supply that runs high, sags low, or fluctuates. Because a poor neutral or ground can distort the voltage the motor sees, the technician also verifies the neutral and ground connections — the same integrity checks tied to the E10 grounding and EEA reversed-polarity codes. This voltage measurement is a technician task described here for information only; it is not a homeowner step.

If the supply is stable and within range, the technician turns to the over-temperature side: checking clearances and ventilation around the furnace, the ambient temperature of the space, and the motor's power module. When voltage and environment both check out and Eb6 still returns, the ECM module may have failed and require replacement.

When to Call a Professional

This code involves components that are not homeowner-serviceable, so have a licensed HVAC technician diagnose and repair it. Keep in mind:

• Eb6 returns after a brief rest instead of clearing on its own
• Blower shutdowns coincide with brownouts or heavy electrical loads in the home
• The furnace is in a hot, poorly ventilated, or tightly enclosed space
• Line voltage and clearances appear normal but Eb6 keeps coming back
• EEA (reversed polarity) or E10 (grounding fault) also appear on the display

✓ Verified against manufacturer service manual — March 2026