Grant Multi Pass Fault codes & diagnostics

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

System Oil 15-26 kW Discontinued

Replaced by: Vortex

The fault code is already on your display

Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →

Fault codes

All 2 documented codes

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Lock-out

Your boiler has stopped working because it failed to ignite the flame during the starting process.

High Engineer only £150-300

Parts commonly replaced

  • Photo cell
  • Control box
  • Oil nozzle
  • Ignition electrodes
Full explanation for Lock-out
Lockout

Your boiler has stopped because it failed to ignite, so it has safely turned itself off to prevent a build-up of fuel.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Photocell
  • Control box
  • Oil nozzle
Full explanation for Lockout