Emergency
B1 on Potterton Gold Heat ErP

Your boiler is flagging a safety concern because the flue terminal is positioned too close to an opening like a window or air vent, which could allow dangerous gases to enter your home.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Above an opening, air brick, opening window etc.

From this model's manual
Verified against the Potterton Gold Heat Erp 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 emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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