JennAir Combination Wall Oven Code F4 E3: exhaust air sensor in the microwave

What F4 E3 means

JennAir combination wall ovens with a microwave section display F4 E3 when there may be a problem with the microwave exhaust air temperature sensor or its wiring. That sensor watches the temperature of the air leaving the microwave cavity. With F4 E3 on the display, the microwave may stop or refuse to run. The microwave may stop mid-cycle and refuse to restart. A cooling-down period often does not clear the code.

Common causes of F4 E3

Exhaust air temperature sensor in the microwave out of range
Loose or damaged sensor wiring
Cooling airflow restricted around the oven

✓ One safe check you can try

1. Press Cancel and let the oven rest for ten minutes. 2. Make sure nothing is blocking the vents around the oven. 3. Flip the breaker off for one full minute, then back on, which clears a stuck exhaust air sensor signal. 4. Run a short microwave test with water. 5. Call us if F4 E3 is still on the display, and mention the exhaust air sensor.

! Why to stop there

The exhaust sensor tells the control whether the microwave is cooling properly.
Testing it means getting into the microwave section.
Ignoring the code risks heat building up in the cabinet.

Opening a panel yourself does not automatically cancel a manufacturer warranty, but it can cause accidental damage, and some manufacturers set their own service conditions. Check your warranty terms, or ask us, before deciding.

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Other Wall Oven codes

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F4 E3F4 E3 questions

What does the exhaust air sensor do?

It measures the air leaving the microwave. The control uses the reading to know whether cooling is working. It measures the air leaving the microwave cavity, so the control knows if cooling is working properly.

Can blocked vents trigger F4 E3?

Restricted airflow can cause real heat, so clearing vents is a sensible step. If the code returns with clear vents, the sensor or its wiring needs testing.

Does the visit include a written price?

Yes, before work begins. Our repairs come with a 30-day workmanship warranty. A written quote comes before work, and a 30-day workmanship warranty follows the repair.