High
5 red flashes on Baxi Suprima 40

Your boiler's internal memory chip has developed a communication fault or failed, meaning the unit cannot store its settings and won't fire up.

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

Parameter storage unit (PSU) error.

From this model's manual
This code was read directly from the manufacturer service manual for this model.
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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Related fault codes

4 red flashesView →

All 23 fault codes on the Suprima 40

Seeing a different code? Every code this model can display, in one place.

1 green flash1 red flash2 red flashes3 green flashes3 red flashes4 green flashes4 red flashes5 green flashes6 green flashes6 red flashes117125160162270C13C33C53Green neonI2HOrange neonRed neon

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