High
Error 20 on Potterton Titanium Combi

Your boiler has stopped working because it can no longer accurately read how hot the internal water temperature is.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

Temperature sensors faulty (DHW and CH sensors)

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

E20View →E28View →

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