LG CH79

High

Multi V5 — Outdoor unit fan operation error (Master: 791, Slave 1: 792, Slave 2: 793).

LG CH79: Outdoor unit fan operation error (Master: 791, Slave 1: 792, Slave 2: 793). This fault noticeably affects operation.

Possible causes

Fan motor defective or assembled incorrectly, or motor U/V/W output has disconnected
Fan PCB is defective

Check steps

Check outdoor unit fan motor assembly for lockup and measure resistance between motor output terminals
Check insulation resistance between fan motor terminals and pipe (>100M ohm), verify terminal-to-PCB wiring matches, and inspect fan PCB IPM

Affected parts

Outdoor fan motor
Fan PCB (IPM)
Motor wiring harness

Safety note

Disconnect power supply before working on the fan motor or fan PCB — rotating parts and high voltage present.

Source: LG resmi servis kilavuzu (bagimsiz cift-dogrulandi) — LG Multi V5 Service Manual (ManualsLib doc #1483751), Error No. 79 "Outdoor unit fan operation error," page 178 (Master: 791, Slave 1: 792, Slave 2: 793); numbering convention confirmed on page 126 (rightmost digit: 1=Master, 2=Slave1, 3=Slave2).

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

Look up in Enthalio →

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