High
8 on Unical Alkon C 28 HE

Your boiler has stopped working because the water pressure inside the heating system has dropped too low.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

WATER DEFICIENCY Insufficient water pressure and consequent intervention of the minimum water pressure - pressure switch ( 13 ). Fill the heating circuit as described in chap. 3.8 and wait for the values to return within default limits. If needed, check the electrical connections and replace the minimum water pressure switch.

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 high 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.

145609111213141516171820212223242627303233384344455355758081

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