Electrolux Refrigerator Error Code 21

Error code 21 indicates an open circuit in the NTC thermistor for the Perfect Temperature Drawer (PTD) chamber. The control board is receiving no usable resistance signal from the drawer temperature sensor, which prevents it from regulating that compartment's temperature. The fault can be in the thermistor itself, the wiring harness, or a connector in the circuit.

A power reset may temporarily clear the code from the display, but it will return as soon as the control board attempts to read the PTD thermistor again and detects the open circuit. The underlying fault, whether a failed thermistor, broken wire, or bad connector, must be physically repaired or replaced before the error will stay cleared.

If only the NTC thermistor needs replacement, parts and labor typically range from around $75 to $200 depending on the specific model and local labor rates. A wiring harness repair or replacement may fall in a similar range, while control board replacement is generally more expensive, often between $200 and $450 including parts and labor. Getting a diagnosis before authorizing parts replacement helps avoid unnecessary costs.

Start by disconnecting the PTD thermistor and measuring its resistance with a multimeter, then compare the reading to the temperature resistance chart for that sensor. If the reading is OL (open/infinite), the thermistor needs to be replaced. If resistance is within spec, inspect and test the wiring harness and connectors for continuity, damage, or corrosion before considering control board replacement.

Error code 21 does not create an immediate safety hazard, but it does mean the Perfect Temperature Drawer is operating without proper temperature monitoring or control. Food stored in that compartment may not be held at the intended temperature, which could affect food safety over time. It is advisable to move temperature-sensitive items to the main refrigerator section until the fault is repaired.