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Blocking - Mains Frequency incorrect or Air Switch Fault on Baxi Suprima 70

Baxi Suprima 70 fault code Blocking - Mains Frequency incorrect or Air Switch Fault

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

What the manual says

Manufacturer manual

>1 min. or Reset button held in to force a restart

From this model's manual
Verified against the Potterton/Potterton Ultra 2 30 Dv installation & service manual.
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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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All 3 fault codes on the Suprima 70

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

Earth Fault or Mains ReversalLockout

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