High
Blocking - Mains Frequency incorrect or Air Switch Fault >1 min. or Reset button held in to force a restart on Baxi Suprima 60

Your boiler has temporarily stopped working because it has detected an issue with the air flow inside or the reset button has been held down for too long.

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

Green LED: ON, Red LED: FLASHING 2 Per Sec.

From this model's manual
Verified against the Baxi/Baxi Potterton Suprima 60 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 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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Boiler cover options

Avoid the next call-out bill

A cover plan would handle faults like Blocking - Mains Frequency incorrect or Air Switch Fault >1 min. or Reset button held in to force a restart: no call-out fees, no surprise bills.

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Related fault codes

Red LED FlashingView →Fan FaultView →

All 4 fault codes on the Suprima 60

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

Blocking - Mains Frequency incorrect or Air Switch FaultEarth Fault or Mains ReversalLockout

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