How much does it cost to fix Alpha error code Section C?

Typical repair cost for the Alpha Section C fault is £80-180 including labour.

Section C High

Alpha Section C Fault Code

Q: What does the Alpha Section C fault code mean?

Your boiler has stopped working because the water pressure inside the system has dropped too low or there is trapped air causing a blockage.

Also written as SECTIONC — same fault.

The Alpha Section C fault code means: your boiler has stopped working because the water pressure inside the system has dropped too low or there is trapped air causing a blockage.. It appears on 1 Alpha model in our database.

Technical description: CH system pressure below 1.0 bar, Pump circulating water (air in system), or Primary flow valve diaphragm damaged / Flow valve rod obstructed

Typical repair cost £80-180 (including labour)

DIY fix possible

Locate the pressure gauge on your boiler; it should be between 1 and 1.5 bar.If the pressure is below 1 bar, use the filling loop (a silver flexi-hose) to carefully top up the system with water until it reaches the green zone.Bleed your radiators to remove any trapped air, then re-check the pressure gauge and top up if necessary.

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Alpha models that show the Section C fault code

Click a model for the full fault code list and model-specific repair notes.

240XE Repair: £80-180

Source

Alpha Section C fault code information on this page is sourced and cross-checked against the official Alpha service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026