Samsung Air Conditioner
Samsung AC E221 error
Outdoor air temperature sensor fault
Try a reset once. If it comes back, a trained technician should repair it.
What it means
The control board is getting a wrong reading, or no reading, from the outdoor air temperature sensor. Usually the sensor, its wire or its plug is loose, damaged or has failed.
Common causes
- Loose or rusted sensor plug on the control board
- Sensor wire cut, pinched or bitten by rats
- Sensor has failed (open or short circuit)
- Less often, a fault on the control board
Try this at home first
Tick each step as you go
When to call a technician
If the code returns after a reset, a technician needs to test and usually replace the sensor. It is a common, low-cost repair.
Safety first
Always switch off at the wall socket or MCB before touching any part. Do not open the outdoor unit, control boards or gas pipes yourself — they carry high voltage and pressure.
Frequently asked questions
What does E221 mean on a Samsung Air Conditioner?
Outdoor air temperature sensor fault. The control board is getting a wrong reading, or no reading, from the outdoor air temperature sensor. Usually the sensor, its wire or its plug is loose, damaged or has failed.
Can I fix Samsung Air Conditioner error E221 myself?
You can try a reset first: Switch off at the wall socket or MCB for 5 minutes, then restart. If the code returns, call a technician.
Is it safe to keep using the Air Conditioner with E221?
Avoid repeated restarts; running with this fault can cause more damage.
Other Samsung AC codes
Sources
We write every explanation in our own words from these references.
- Samsung Support — Error codes on Samsung indoor unit air conditioner
- BOXT — Samsung air conditioning fault codes
- PickHVAC — Samsung mini split error codes
Last checked: 2026-10-20