Gree F1

What does Gree F1 mean?

F1 means the indoor room ambient temperature sensor is open- or short-circuited. The control board cannot read indoor air temperature, so it shuts the system down. In cooling, fan or dry mode the indoor fan keeps running while the compressor and outdoor fan stop; in heating all loads stop. The unit displays F1.

Symptoms

• Display shows F1
• In cool/fan/dry the indoor fan runs but compressor and outdoor fan stop; in heat all loads stop
• Unit will not hold a setpoint or cool/heat normally
• Fault appears at power-up or shortly after starting

Common causes

• Room temperature sensor not connected well at the terminal
• Temperature sensor damaged
• Sensor connection wire short-circuited or broken
• Indoor unit main board fault

Diagnostic steps

1. 01

   Check the sensor connection

   Verify the connection terminal between the temperature sensor and the control board is not loose or poorly connected; reseat the sensor firmly.

2. 02

   Check for a short from tripped parts

   Look for a short circuit caused by parts that have tipped over against the control board; set the parts upright.

3. 03

   Test the sensor resistance

   Measure the sensor resistance and compare it against the manual's temperature-sensor resistance table; if it is out of range, replace it with a sensor of the same model.

4. 04

   Replace the main board

   If the sensor and wiring are good, replace the controller (indoor main board) with one of the same model.

When to call a professional

Reseating a connector is within reach of an experienced owner, but verifying a sensor against the resistance table and replacing the indoor main board call for a meter and Gree service parts. If F1 returns after reseating the sensor, or you are not comfortable working inside the powered control box, hand the diagnosis to a licensed HVAC technician.