Fault Codes / Gree / U4

Gree U4

High

GMV6 — Refrigerant-lacking protection

Gree U4: Refrigerant-lacking protection This fault noticeably affects operation.

Possible causes

Refrigerant leak in the system
Insufficient initial charge after installation/service

Check steps

Leak-check the system (electronic leak detector/bubble spray)
Evacuate and recharge refrigerant per nameplate after repair

Affected parts

Soğutucu akışkan devresi
Servis vanaları

Safety note

Refrigerant under pressure — wear safety glasses/gloves

Source: Gree resmi servis kilavuzu (bagimsiz cift-dogrulandi) — Gree GMV6 Series Service Manual, ManualsLib (manual/1906369), fault-code tablosu, p.77: "U4: Refrigerant-lacking protection". Not: kaynak "Chapter 5 Maintenance" olarak veriliyor ancak WebFetch ile erişimde bu kayıt "Chapter 3 (Faults) / Debugging" bölümünde görüldü — bölüm adı bağımsız olarak PDF üzerinde gözle…

Reviewed by Anıl Güzeldemir — in the refrigeration machine room since 2006, developer of Enthalio.

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