Emergency
ALL03 on Sime iQE Simplicity 20T

Your boiler has too much water inside it, causing the internal pressure to rise to an unsafe level.

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

The system pressure detected is more than 2.8 bar. Ensure that the filling loop is turned off and the pipe detatched. Lower the system pressure by draining from a radiator, if problem persists seek help from a qualified engineer.

From this model's manual
Verified against the Sime Iqe Simplicity 20t installation & service manual, page 8.
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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