Emergency
E48 on Warmflow Agentis Boilerhouse

Your boiler has detected that there is too much water pressure in the system, which is preventing it from running safely.

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

High System Pressure — filling loop left connected/open; insufficient expansion capacity; consult Service Engineer

From this model's manual
Verified against the Warmflow Agentis Internal 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 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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Related fault codes

E47View →E49View →

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