Emergency
45 on Unical Alkon C 28 HE

Your boiler has stopped working because the water pressure inside the system has risen dangerously high above the safe limit.

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

WATER OVERPRESSURE detected if the H2O pressure Transducer is present with pressure > 2.5 bar; it is reset automatically when H2O pressure < 2 bar. Wait for the values to return to default limits / Replace the Transducer

From this model's manual
Verified against the Unical/Unical Alkon C 28 He 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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All 33 fault codes on the Alkon C 28 HE

Seeing a different code? Every code this model can display, in one place.

14568091112131415161718202122232426273032333843445355758081

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