BoilerFaultCodesIdeal L12 Fault Code
The Ideal L12 fault code means: your heat pump has shut down because a power component is drawing too much electricity, likely due to a blockage or a part wearing out.. It appears on 1 Ideal model in our database.
Technical description: Inverter High Current
What causes the Ideal L12 fault?
This fault occurs when the internal electrical components detect a sudden spike in power consumption, triggering an immediate shutdown to prevent a fire or permanent damage. The most common reasons are a blockage in the refrigeration circuit causing the pump to strain, or a mechanical failure within the compressor itself. It can also be caused by an electrical short-circuit in the control boards that drive the system.
This fault is more frequent during the first cold snaps of winter, as the system has to work at its maximum capacity and any struggling components are likely to fail under the increased load.
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 L12 fault code
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Source
Ideal L12 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