BoilerFaultCodesIdeal L46 Fault Code
The Ideal L46 fault code means: your heat pump's internal computer system has detected a communication or electrical issue with the power supply that controls the compressor.. It appears on 1 Ideal model in our database.
Technical description: Inverter Error
What causes the Ideal L46 fault?
This fault occurs when there is a breakdown in communication between the heat pump's brains and the power system that drives the compressor. It is usually caused by an electrical failure on the inverter circuit board or a loose connection in the high-voltage wiring that prevents the system from regulating power safely.
This fault is more common during summer heatwaves or extreme winter cold, as the inverter components are pushed to their thermal limits while trying to maintain indoor comfort.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Ideal models that show the L46 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ideal L46 fault code information on this page is sourced and cross-checked against the official Ideal service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026