Amana AMVM970803BN Error Code E15: Return Air Temperature Sensor Open (External)
What Does Code E15 Mean?
Error code E15 on the Amana AMVM970803BN indicates the external return air temperature sensor circuit is open. This means the control board is not receiving a valid reading from this sensor, so the return air temperature will not appear in the CoolCloud HVAC App. The furnace itself should continue to operate normally in most cases.
An open circuit in a temperature sensor typically means the sensor probe is disconnected, the connector is not fully seated, or the sensor probe has failed and measures an out-of-range resistance. This furnace uses a 10k-ohm thermistor sensor that should measure approximately 10,000 ohms at 77°F — a reading significantly different from this indicates a failed sensor. An improperly crimped connector can also create an intermittent or permanent open.
A technician should verify the external return air sensor probe is fully plugged in, check that the connector is properly crimped, and measure the resistance across the sensor probe at a known temperature to confirm it is within specification. If the resistance is incorrect, the sensor probe must be replaced. If the sensor and wiring check out, the PCB may need replacement.
Common Causes
When to Call a Professional
Contact a licensed HVAC technician if:
- E15 persists after checking that the sensor probe is fully seated — a technician must verify the connector crimp and measure sensor resistance
- If the sensor probe resistance does not measure approximately 10k ohm at 77°F, the sensor must be replaced
- If the sensor and wiring test correctly but E15 continues, the PCB may need replacement
✓ Verified against manufacturer service manual — March 2026