Daikin L4

High

VRV / Sky Air — Inverter heat sink (fin) temperature rise.

Daikin L4: Inverter heat sink (fin) temperature rise. This fault noticeably affects operation.

Possible causes

Heat sink dusty / ventilation blocked.
High ambient temperature.
Poor thermal paste/mount at IPM.

Check steps

Clean heat sink & ventilation paths.
Check fin thermistor & IPM mounting.

Affected parts

Kühlkörper-Thermistor
Inverter-Platine

Safety note

High voltage! Let capacitors discharge.

Source: Daikin SM-TS3 (Simple Self-Diagnosis by Malfunction Code, resmi) veya VRV IV+ Service Manual (ManualsLib) — SM-TS3 p.4: L4 'Malfunction of inverter radiation fin temperature rise' — RA/SkyAir/VRV/Package/Chiller checked. Matches.

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

Look up in Enthalio →

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