Johnson Starley 2.70 Fault Code
Also written as 270 — same fault.
The Johnson Starley 2.70 fault code means: your boiler has detected an internal communication error between its main control components, causing it to shut down for safety.. It appears on 1 Johnson Starley model in our database.
Technical description: 21
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Johnson Starley models that show the 2.70 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Johnson Starley 2.70 fault code information on this page is sourced and cross-checked against the official Johnson Starley service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026