What F3H means
F3H means there may be a problem with the humidity thermistor or its associated wiring. Humidity sensing is what sensor cooking and sensor reheat programs use to judge when food is done, so those programs are the ones most likely to stop or refuse to start. Cooking by time and power level does not depend on that reading in the same way, and the thermistor needs a technician if F3H returns after a reset.
Error codes
Reference| Code | Meaning |
|---|---|
| F3H | There may be a problem with the Humidity Thermistor or the associated wiring. |
What the oven does alongside F3H
- Sensor reheat or sensor cook stopping with F3H — The program cannot read the steam it relies on to judge doneness.
- Auto programs that refuse to start — Programs built on humidity sensing are blocked without a usable reading.
- Timed cooking that still runs normally — Cooking by time and power does not wait for a humidity reading on most units.
- Food that came out wrong before the code appeared — A thermistor that was reading poorly before it failed outright.
What triggers F3H, most likely first
- The humidity thermistor — First: the part the documentation names, and the one exposed to steam and grease in the air leaving the cavity.
- The connector at the thermistor — Second: terminals in a humid air path can corrode or loosen over time.
- The wiring between thermistor and control — Third: a lead disturbed during an earlier repair, or aged by heat inside the cabinet.
- A one-off misread — Last: a code that clears with a reset and does not return.
Check order for F3H, and why
- Reset with the power off — A free first check that rules out a passing glitch.
- Compare a sensor program with timed cooking — If only sensor programs fail, the humidity circuit is confirmed as the area to test.
- Note whether F3H appears at once or partway through — At once suggests an open circuit; partway suggests a reading that drifts as steam builds.
- Have the thermistor and wiring tested — A technician reaches them by opening the cabinet and measures against the tech sheet.
Reset and owner-safe checks
- Reset the unit — Unplug it or switch off its breaker for a minute, then restore power.
Tools: breaker panel accessAbout 3 min
- Run a sensor program with food or water inside — Never run the unit empty; use food or a microwave-safe cup of water and note whether F3H returns.
Tools: microwave-safe cupAbout 5 min
- Cook by time and power meanwhile — Set the time and power level yourself, as the manual describes, and check the food as it cooks.
Tools: owner's manual
- Record what happened — Note which program was running and when the code appeared, for the booking.
Tools: pen and paperAbout 2 min
Before any panel comes off
Safety
Unplug the unit or switch off its breaker before cleaning it; a capacitor can hold a charge after the power is off. Never remove the outer cabinet of a microwave or combination unit: the high-voltage capacitor inside can hold a lethal charge after unplugging, and the door switches must never be defeated. If the unit can microwave, never run it empty to test it, as that can damage the parts that generate the microwaves.
When F3H needs a technician
Call if F3H returns after a reset, if every sensor program fails, or if you would rather not cook by time and power for long. The humidity thermistor is reached by opening the cabinet, which is a technician task, and the technician checks its connector and wiring before fitting a new part.
Other Amana oven codes
Which models this reading covers
This reading of F3H applies to Amana units whose control reports the humidity thermistor or its wiring with this code, as the table states, most often units with humidity-based sensor programs. Programs and part locations vary by model, and a model-specific page, where one exists, is the better guide. None is listed for F3H yet; start at the Amana oven code index below.
Amana oven code index
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