Whirlpool Cooktop F21 — What It Means & How to Fix It
F21 means either a problem with the power supply frequency or, on radiant models, the cooktop overheating — let it cool for about 5 minutes and check the installation and airflow.
What this code means
Whirlpool publishes two explanations. One: there is a problem with power supply frequency. The other, for radiant cooktops: there may be a problem with the cooktop overheating — verify installation and allow it to cool approximately 5 minutes.
Meaning depends on cooktop type.
Most likely causes
| Cause | How likely | DIY-fixable? |
|---|---|---|
| Cooktop overheated (radiant models) | Common | Yes — let it cool |
| Restricted airflow under the cooktop | Common | Yes — clear cabinet |
| Power supply frequency problem | Occasional | No — electrician |
What you can try yourself
- Turn the cooktop off and let it cool for about 5 minutes.
- Check nothing in the cabinet below blocks airflow.
- Reset power at the breaker for one minute.
- If F21 returns on a cool cooktop, have an electrician check the supply or call service.
When to call a technician
- Repeat code when cool.
- Running on a generator or unstable supply.
- Cabinet underneath very hot.
Typical professional repair cost: Often free; electrician visit $100–$250.
Frequently asked questions
What does F21 mean?
A power supply frequency problem, or overheating on radiant cooktops.
How long should I let it cool?
Approximately 5 minutes.
Could a generator cause it?
Whirlpool only says power supply frequency; unstable supplies are worth ruling out with an electrician.
Sources checked
- Whirlpool Product Help: F21 - Electric Cooktop
- Whirlpool Product Help: F21 - Radiant - Electric Cooktop
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 Cooktop F0 F0 or F00 means an object, liquid or soil is putting pressure on the touch control panel — remove anything on the control area, wipe it clean and dry, and reset power if needed.
- Whirlpool Cooktop F1E0 F1E0 indicates one or more keys are permanently pressed — turn the controls off, clear and thoroughly clean the touch panel, and reset power; if it persists the cooktop control may be at fault.
- Whirlpool Cooktop F2 E1 F2 E1 points to the keys: food, water or build-up may be hindering the controls, so clean the area with soap and water, dry it with a microfiber towel, and reset power.
- Whirlpool Cooktop F1E1 F1E1 means communication has been lost between the user interface (keypad) and the appliance manager board; reset power for a minute and call service if it returns.
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