H00 266 High

Potterton H00 266 Fault Code

Also written as H00266 — same fault.

The Potterton H00 266 fault code means: your boiler is experiencing a communication error with its internal water pressure sensor, which prevents it from safely operating your heating or hot water.. It appears on 1 Potterton model in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Boiler Control Assembly (Use with ‘Huba’pressure transmitter only)
Typical repair cost £150-250 (including labour)

Engineer required

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

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Potterton models that show the H00 266 fault code

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

Source

Potterton H00 266 fault code information on this page is sourced and cross-checked against the official Potterton service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026