Ideal Combi i 30 Fault codes & diagnostics

4 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.

Combi Natural Gas 2011-present
GC Number 47-348-83
Download the Ideal Combi i 30 manualThe official installation and service manual (PDF), the document these fault codes were read from. PDF

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Fault codes

All 4 documented codes

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C & 0

Your boiler's internal memory chip is not communicating correctly with the main computer, preventing the boiler from starting safely.

High Engineer only £150-250

Parts commonly replaced

  • Boiler Control Card (BCC)
  • Wiring harness

Related codes

Full explanation for C & 0
C & 2

Your boiler's electronic memory card is not being recognised, which prevents the system from starting up safely.

High Engineer only £150-300

Parts commonly replaced

  • Boiler Chip Card (BCC)
  • Main PCB
Full explanation for C & 2
F1

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

High DIY-safe £80-120

What to check first

  1. Locate the internal filling loop, which is usually a small silver lever or a braided hose under the boiler.
  2. Open the filling valve slowly until the pressure gauge on the front of the boiler reads between 1.0 and 1.5 bar.
  3. Close the valve tightly and check that the fault code disappears.

Parts commonly replaced

  • Pressure sensor
  • Filling loop
  • Pressure relief valve

Related codes

Full explanation for F1
L2

Your boiler has tried to start up several times but couldn't successfully light the flame.

High Engineer only £100-£250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • PCB

Related codes

Full explanation for L2
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