Medium
12 on Worcester Bosch Greenstar i Junior

Your boiler has detected that the water pressure is either too low or too high, or the gauge itself is reporting an incorrect reading.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Pressure gauge

From this model's manual
Verified against the Worcester Bosch Greenstar I Junior 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.

DIY fix possible

Check the pressure gauge on the front of the boiler; it should be between 1 and 1.5 bar.If the pressure is below 1 bar, use the internal filling link to top up the system.If the pressure is above 2.5 bar, bleed a radiator to release the excess pressure.

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