Fault Codes / Gree / U3

Gree U3

Critical

GMV6 — Power phase sequence protection

Gree U3: Power phase sequence protection This fault typically halts operation and needs immediate attention.

Possible causes

Two of the mains phases L1/L2/L3 are swapped
Faulty phase-sequence detection circuit on the main board

Check steps

Measure phase sequence with a phase rotation tester and swap two phases if needed
Check mains terminal connections for tightness

Affected parts

Dış ünite ana kartı
Şebeke bağlantı terminali

Safety note

High-voltage 3-phase supply — de-energize before servicing; qualified electrician only

Source: Gree resmi servis kilavuzu (bagimsiz cift-dogrulandi) — Gree GMV6 Series Service Manual, ManualsLib (manual ID 1906369), Chapter 3 "Faults", p.77: U3 = "Power phase sequence protection" — bağımsız olarak doğrulandı: manuel sayfası (https://www.manualslib.com/manual/1906369/Gree-Gmv6-Series.html?page=77) doğrudan çekildi ve U-serisi tam tabloda (U0 preheat, U2 capacity c…

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