BoilerFaultCodesYour boiler is currently performing a self-test of its internal pressure sensor and has temporarily paused heating until it finishes.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Water pressure sensor test running, heating demands are blocked
What causes this fault?
This occurs when the boiler performs a routine safety check to ensure the water pressure sensor is measuring accurately. It is usually a temporary phase during startup or after a refill where the system monitors for pressure stability before firing the burner. If the code persists, it often suggests the sensor is struggling to get a consistent reading or the expansion vessel is failing to regulate pressure changes.
DIY fix possible
Wait up to 15 minutes for the automated test to completeEnsure your system water pressure is within the green zone on the digital displayIf the code persists, try restarting the boiler using the power button
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