E78-236 High

Potterton E78-236 Fault Code

Also written as E78236 — same fault.

The Potterton E78-236 fault code means: your boiler is failing to detect the gas flow required to ignite, meaning it cannot produce heat or hot water because the internal gas supply component is not responding correctly.. 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: Gas Valve Assembly CFL/RSL40 - 100
Typical repair cost £250-450 (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 E78-236 fault code

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

Source

Potterton E78-236 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