BoilerFaultCodesTechnical description
Water pressure sensor check is running, demand (DHW or heating) is blocked
What causes this fault?
This status occurs when the boiler's internal computer is verifying that there is enough water pressure and flow before it safely ignites the burner. It is often triggered if the water pressure sensor or temperature sensors are sending slightly inconsistent readings or taking too long to respond. While it is usually just a brief safety check, if it persists, it typically means a sensor is beginning to fail or there is a minor circulation issue.
DIY fix possible
Wait for up to 15 minutes to see if the code clears automaticallyCheck that the pressure gauge is between 1.0 and 1.5 barRestart the boiler using the reset button if the code remains for more than 20 minutes
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