PP/LL Low

Ariston PP/LL Fault Code

Also written as PPLL — same fault.

The Ariston PP/LL fault code means: your boiler is currently just notifying you that it is adjusting its internal ignition power level; this is a normal operational message rather than a breakdown.. It appears on 3 Ariston models in our database.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description: Soft light power (expressed in a percentage of the difference between the maximum power allowed by the boiler and the minimum)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Ariston models that show the PP/LL fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Ariston PP/LL fault code information on this page is sourced and cross-checked against the official Ariston service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026