Gree H6

What does Gree H6 mean?

H6 is a blocked-protection fault on the indoor unit (IDU) fan motor. The unit stops and the display shows H6. The troubleshooting procedure checks the indoor fan motor and the mainboard detection circuit.

Symptoms

• Display shows H6
• Indoor fan does not operate
• Complete unit stops
• Fan blade may be physically stiff or jammed when turned by hand

Common causes

• Fan blade jammed so the rotor cannot turn smoothly
• Wiring terminal between the indoor fan and main board loose
• Indoor fan motor damaged
• Indoor unit main board fault

Diagnostic steps

1. 01

   Turn the blade by hand

   With power off, turn the fan blades by hand; if they do not run smoothly, adjust the motor and blade assembly so the rotor turns freely, then power up and check if the fault clears.

2. 02

   Reseat the motor wiring

   With power off, check whether the wiring terminal between the indoor fan and the main board is loose, and reinsert it.

3. 03

   Check the motor drive voltages

   Power up and measure the motor interface voltages — terminal 1 to 2 should be about 280–310 VDC, terminal 2 to 3 about 15 VDC, and a feedback voltage should be present at terminal 2 to 4; missing voltages point to a main board fault.

4. 04

   Replace the main board

   If the drive voltages are wrong, replace the main board with one of the same model.

5. 05

   Replace the motor

   If the board outputs are correct but the fan still will not run, replace the indoor fan motor with one of the same model.

When to call a professional

Freeing a stuck blade is straightforward with power off, but probing the motor interface for 280–310 VDC means working inside a live control box, and replacing a DC/PG fan motor or the main board needs matching Gree parts. If H6 stays after clearing an obvious jam and reseating the connector, have a licensed HVAC technician take the voltage readings and swap parts.