Whirlpool Microwave Error Code F3H — Humidity Sensor Open Circuit
What this means
The F3H error code on Whirlpool microwaves indicates the humidity sensor has an open circuit. The humidity sensor detects moisture levels in the cooking chamber to automatically determine when food is done during auto-cook and auto-reheat modes. An open circuit means the sensor wire is broken or the sensor element has failed. Manual time/power cooking will still work normally.
Alternate codes: F3 H
Step-by-step fix
3 stepsPower cycle and test auto-cook
Unplug for 5 minutes. Try an auto-cook or auto-reheat function. If it works, the sensor had a temporary issue.
Heavy steam from previous cooking can temporarily affect sensor readings.
Use manual cooking as a workaround
While waiting for repair, you can continue using the microwave with manual time and power level settings.
All manual cooking functions should work normally — only auto-sense features are affected.
Schedule professional sensor replacement
The humidity sensor is located inside the microwave cabinet. Professional service is required to access and replace it safely.
This is not an urgent repair — the microwave is still usable with manual settings.
When to call a professional
Sensor replacement requires accessing the interior of the microwave cabinet. Always hire a professional for this repair.
Related error codes
Information compiled from manufacturer service manuals, official troubleshooting documentation, and appliance repair industry resources. This guide is for informational purposes only — always consult a qualified technician for complex repairs.
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