Whirlpool Microwave E21 — What It Means & How to Fix It
Also shown as E22 on some models.
E21 means the thermal sensor circuit reported open and E22 that it reported a short — reset power for a minute, and have a technician check the sensor, control board or wiring if it returns.
What this code means
Whirlpool says E21 is the thermal sensor circuit reporting open to the control board and E22 the same circuit reporting a short. In both cases there may be a problem with the thermal sensor, the appliance control board, or the associated wiring.
Whirlpool over-the-range microwaves.
Most likely causes
| Cause | How likely | DIY-fixable? |
|---|---|---|
| Thermal sensor failed | Common | No — technician job |
| Sensor wiring open or shorted | Common | No — technician job |
| Control board fault | Occasional | No — technician job |
What you can try yourself
- Breaker off for one minute, then on.
- Watch the display for one minute.
- Verify the microwave heats a cup of water.
- Call for service if the code is back.
When to call a technician
- Repeat code.
- Microwave shuts off mid-cycle.
- Cabinet becomes very hot.
Typical professional repair cost: About $120–$300 depending on the part.
Frequently asked questions
What is the difference between E21 and E22?
E21 is an open thermal sensor circuit; E22 is a shorted one.
What does the thermal sensor do?
It reports temperature to the control board so the oven can regulate and protect itself.
Is it safe to keep using it?
Not with a returning code — the control cannot rely on its temperature reading.
Sources checked
- Whirlpool Product Help: E21 - Over-the-Range Microwave
- Whirlpool Product Help: E22 - Over-the-Range Microwave
Error meanings can vary by model. This guide was checked against the documentation above; use the manual for the model number on your own appliance when it differs.
Related Whirlpool codes
- Whirlpool Microwave E03 E03 — or a plain F2 — means the keypad reported a problem to the control board; reset power for one minute and call for service if it comes back.
- Whirlpool Microwave SE SE means there is a problem with the keypad (user interface) or its wiring — clean and dry the panel, reset power for a minute, and call service if SE remains.
- Whirlpool Microwave E11 E11 and E12 point to the microwave's gas sensor — the sensor used for automatic cooking — or its wiring; reset power for a minute, and expect to need a technician if it returns.
- Whirlpool Microwave E13 E13 means the oven did not pre-heat correctly, with a possible problem in the appliance control board or its wiring; reset power for a minute and call service if it repeats.
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