Medium Warning
S.76 on Glow-worm Ultracom 2 HXI

Your boiler has paused because it is waiting for a stable reading from the internal water pressure sensor.

Book a service

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

Technical description

Waiting period – pressure sensor

What causes this fault?

This fault occurs when the boiler's control panel cannot get a consistent or reliable signal from the internal water pressure sensor. It usually happens because the sensor itself has developed an electrical fault or is being affected by debris and sludge within the heating system. In some cases, a loose or damaged wiring connection between the sensor and the main board is preventing the boiler from confirming there is enough water to operate safely.

DIY fix possible

Check the pressure gauge on the front of the boilerIf the pressure is below 1.0 bar, use the filling loop to top it up to 1.5 barReset the boiler to see if the status code clears

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