Gree E4 fault code

What it means

Compressor discharge high-temperature protection

Discharge temperature has risen far enough for the unit to protect the compressor. On a refrigeration circuit this is a charge, metering or heat-rejection question before it is an electrical one.

Safety: Discharge pipework runs very hot — allow to cool.

UK models this code applies to

From the Gree service literature we hold (Gree (Zhuhai) Service Manual, Bora Inverter R32 §9.1 Error Code List) — not a scraped list.

Now the harder half: proving what caused it

E4 names a symptom, not a root cause. In the app, the same code opens a guided investigation: what to measure first, the expected values for your exact model, and an honest verdict — including “nothing in this machine is broken” when that's what the readings say.