E251

Compressor Discharge Temperature Sensor Error

Home Appliance Error Codes Samsung Split AC

Can you still use it? With care until repaired

Who can fix it? Needs a technician

Typical repair time 30 minutes – 3 hours

Typical cost SAR 80 to 2,500

What it means

This code appears on Samsung inverter split wall units such as WindFree and Digital Inverter. It means the thermistor on the compressor discharge pipe is open or shorted. This sensor is one of the main compressor overheating protections, so the compressor will not run until it is fixed. The same code can mean something else on other brands.

Models covered: Samsung inverter split air conditioners (e.g. WindFree and Digital Inverter wall units) that show three-digit E codes on the display.

Symptoms3

E251 shows and the compressor does not run.
The indoor fan runs without cooling.
The code may appear once the compressor heats up if the wire is heat-damaged.

Possible causes5

Loose or corroded sensor plug.
Sensor worn out by high discharge pipe temperature over time.
Wire melted or cut from touching the hot pipe or compressor body.
Insects or moisture inside the outdoor board box.
Faulty sensor input on the outdoor PCB.

How to diagnose5

Switch off the breaker for a few minutes, then restart.
After discharge, a technician checks the sensor on the discharge pipe, its wire and plug.
Measure the sensor resistance against the Samsung table.
Look for melted or chafed wire near the compressor.
If the sensor is good, check the sensor input on the outdoor board.

How to fix5

Secure and clean the plug.
Repair the wire and hold it away from the hot pipe with proper ties.
Replace the discharge sensor.
Replace the outdoor PCB if its sensor input is faulty.
Run the unit until the compressor is hot and confirm the code does not return.

Repair cost

0–200

200–600

600–1,500

1,500+

In Saudi riyals; the highlighted part is the expected range for this fault.

The usual fix is a low-cost sensor; the top of the range covers the outdoor PCB.

Prices are rough estimates including the part and the technician’s fee, and vary with brand, model and part source.
Prices last updated: September 2026

Frequently asked questions

What is the difference between E251 and E416?

E251 means the discharge sensor itself has failed. E416 means the sensor works and reads a genuinely high discharge temperature, often from low refrigerant.

Can the sensor be bypassed to run the AC?

No. That puts the compressor at risk: the sensor protects it from overheating, and bypassing it can destroy the most expensive part of the unit.

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This guide is for information only and does not replace an inspection by a qualified technician. If the fault involves brakes, steering, engine temperature, electrics or refrigerant, do not attempt the repair yourself.

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