Gree U8 Error Code – Exhaust Temperature Sensor Disconnection

Power Cycle Unit
Turn off the unit at the circuit breaker. Wait 5 minutes, then turn it back on. Check if error U8 clears. 🔧 None

Locate the Sensor
Open the unit cover and locate the relevant thermistor/sensor. Refer to the service manual wiring diagram for the exact sensor position. 🔧 Screwdriver, flashlight

Check Sensor Connector
Disconnect and reconnect the sensor connector on the PCB. Inspect for corrosion, bent pins, or loose connections. 🔧 Needle-nose pliers

Measure Sensor Resistance
Using a multimeter set to Ohms, measure resistance across sensor terminals. At 25C should read approximately 10k-Ohm. Refer to service manual for the temperature-resistance table. 🔧 Digital multimeter ⚠️ Disconnect power before measuring sensor resistance

Replace Sensor
If resistance is out of range (open circuit or short circuit), replace the NTC thermistor sensor. Order the correct part using the model number. 🔧 Soldering iron or connector tool