High
2.7bar on Saunier Duval Thelia 23E

Your boiler's internal water pressure is currently too high, which can cause the safety valve to leak or performance issues.

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.

What the manual says

Manufacturer manual

Upper water pressure (>2.7b)

From this model's manual
Verified against the Saunier Duval Thelia 23e installation & service manual, page 37.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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