High
Mains ON Only on Potterton Prima 30B

Your boiler has detected an internal fault that has caused it to stop heating your home and hot water for safety reasons.

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: OFF, Red LED: ON

From this model's manual
Verified against the Potterton Prima 30b installation & service manual, page 20.
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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